Athena Widget Set - C Language Interface

X Consortium Standard

Chris D. Peterson

formerly MIT X Consortium

X Version 11, Release 7.7

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Table of Contents

1. Athena Widgets and The Intrinsics

    Introduction to the X Toolkit
    Terminology
    Underlying Model
    Conventions Used in this Manual
    Format of the Widget Reference Chapters
    Input Focus

2. Using Widgets

    Using Widgets

        Setting the Locale
        Initializing the Toolkit
        Creating a Widget
        Common Resources
        Resource Conversions
        Realizing a Widget
        Processing Events
        Standard Widget Manipulation Functions
        Using the Client Callback Interface
        Programming Considerations
        Example Programs

3. Simple Widgets

    Command Widget

        Resources
        Command Actions

    Grip Widget

        Resources
        Grip Actions

    Label Widget

        Resources

    List Widget

        Resources
        List Actions
        List Callbacks
        Changing the List
        Highlighting an Item
        Unhighlighting an Item
        Retrieving the Currently Selected Item
        Restrictions

    Panner Widget

        Resources
        Panner Actions
        Panner Callbacks

    Repeater Widget

        Resources
        Repeater Actions

    Scrollbar Widget

        Resources
        Scrollbar Actions
        Scrollbar Callbacks
        Convenience Routines
        Setting Float Resources

    Simple Widget

        Resources

    StripChart Widget

        Resources
        Getting the StripChart Value

    Toggle Widget

        Resources
        Toggle Actions
        Toggle Actions
        Radio Groups
        Convenience Routines

4. Menus

    Using the Menus
    Sme Object

        Resources
        Subclassing the Sme Object

    SmeBSB Object

        Resources

    SmeLine Object

        Resources

5. Text Widgets

    Text Widget for Users

        Default Key Bindings
        Search and Replace
        File Insertion
        Text Selections for Users

    Text Widget Actions

        Cursor Movement Actions\fP
        Delete Actions
        Selection Actions
        The New Line Actions
        Kill and Actions
        Miscellaneous Actions
        Text Selections for Application Programmers

    Default Translation Bindings
    Text Functions

        Selecting Text
        Unhighlighting Text
        Getting Current Text Selection
        Replacing Text
        Searching for Text
        Redisplaying Text
        Resources Convenience Routines

    Customizing the Text Widget
    Text Widget

        Resources

    TextSink Object

        Resources
        Subclassing the TextSink

    TextSrc Object

        Resources
        Subclassing the TextSrc

    Ascii Sink Object and Multi Sink Object

        Resources

    Ascii Source Object and Multi Source Object

        Resources
        Convenience Routines

    Ascii Text Widget

        Resources

6. Composite and Constraint Widgets

    Box Widget

        Resources
        Layout Semantics

    Dialog Widget

        Resources
        Constraint Resources
        Layout Semantics
        Automatically Created Children.
        Convenience Routines

    Form Widget

        Resources
        Constraint Resources
        Layout Semantics
        Convenience Routines

    Paned Widget

        Using the Paned Widget
        Resources
        Constraint Resources
        Layout Semantics
        Grip Translations
        Convenience Routines

    Porthole Widget

        Resources
        Layout Semantics
        Porthole Callbacks

    Tree Widget

        Resources
        Constraint Resources
        Layout Semantics
        Convenience Routines

    Viewport Widget

        Resources
        Layout Semantics

7. Creating New Widgets (Subclassing)

    Public Header File
    Private Header File
    Widget Source File

8. Acknowledgments

Chapter 1. Athena Widgets and The Intrinsics

Table of Contents

Introduction to the X Toolkit
Terminology
Underlying Model
Conventions Used in this Manual
Format of the Widget Reference Chapters
Input Focus

The X Toolkit is made up of two distinct pieces, the Xt Intrinsics and a widget
set. The Athena widget set is a sample implementation of a widget set built
upon the Intrinsics. In the X Toolkit, a widget is the combination of an X
window or subwindow and its associated input and output semantics.

Because the Intrinsics provide the same basic functionality to all widget sets
it may be possible to use widgets from the Athena widget set with other widget
sets based upon the Intrinsics. Since widget sets may also implement private
protocols, all functionality may not be available when mixing and matching
widget sets. For information about the Intrinsics, see the X Toolkit Intrinsics
- C Language Interface.

The Athena widget set is a library package layered on top of the Intrinsics and
Xlib that provides a set of user interface tools sufficient to build a wide
variety of applications. This layer extends the basic abstractions provided by
X and provides the next layer of functionality primarily by supplying a
cohesive set of sample widgets. Although the Intrinsics are a Consortium
standard, there is no standard widget set.

To the extent possible, the Intrinsics are "policy-free". The application
environment and widget set, not the Intrinsics, define, implement, and enforce:

  * Policy

  * Consistency

  * Style

Each individual widget implementation defines its own policy. The X Toolkit
design allows for, but does not necessarily encourage, the free mixing of
radically differing widget implementations.

Introduction to the X Toolkit

The X Toolkit provides tools that simplify the design of application user
interfaces in the X Window System programming environment. It assists
application programmers by providing a set of common underlying user-interface
functions. It also lets widget programmers modify existing widgets, by
subclassing, or add new widgets. By using the X Toolkit in their applications,
programmers can present a similar user interface across applications to all
workstation users.

The X Toolkit consists of:

  * A set of Intrinsics functions for building widgets

  * An architectural model for constructing widgets

  * A widget set for application programming

While the majority of the Intrinsics functions are intended for the widget
programmer, a subset of the Intrinsics functions are to be used by application
programmers (see X Toolkit Intrinsics - C Language Interface). The
architectural model lets the widget programmer design new widgets by using the
Intrinsics and by combining other widgets. The application interface layers
built on top of the X Toolkit include a coordinated set of widgets and
composition policies. Some of these widgets and policies are specific to a
single application domain, and others are common to a variety of applications.

The remainder of this chapter discusses the X Toolkit and Athena widget set:

  * Terminology

  * Model

  * Conventions used in this manual

  * Format of the Widget Reference Chapters

Terminology

In addition to the terms already defined for X programming (see Xlib - C
Language Interface), the following terms are specific to the Intrinsics and
Athena widget set and used throughout this document.

Application programmer

  * A programmer who uses the X Toolkit to produce an application user
    interface.

Child

  * A widget that is contained within another "parent" widget.

Class

  * The general group to which a specific object belongs.

Client

  * A function that uses a widget in an application or for composing other
    widgets.

FullName

  * The name of a widget instance appended to the full name of its parent.

Instance

  * A specific widget object as opposed to a general widget class.

Method

  * A function or procedure implemented by a widget class.

Name

  * The name that is specific to an instance of a widget for a given client.
    This name is specified at creation time and cannot be modified.

Object

  * A data abstraction consisting of private data and private and public
    functions that operate on the private data. Users of the abstraction can
    interact with the object only through calls to the object's public
    functions. In the X Toolkit, some of the object's public functions are
    called directly by the application, while others are called indirectly when
    the application calls the common Intrinsics functions. In general, if a
    function is common to all widgets, an application uses a single Intrinsics
    function to invoke the function for all types of widgets. If a function is
    unique to a single widget type, the widget exports the function.

Parent

  * A widget that contains at least one other ("child") widget. A parent widget
    is also known as a composite widget.

Resource

  * A named piece of data in a widget that can be set by a client, by an
    application, or by user defaults.

Superclass

  * A larger class of which a specific class is a member. All members of a
    class are also members of the superclass.

User

  * A person interacting with a workstation.

Widget

  * An object providing a user-interface abstraction (for example, a Scrollbar
    widget).

Widget class

  * The general group to which a specific widget belongs, otherwise known as
    the type of the widget.

Widget programmer

  * A programmer who adds new widgets to the X Toolkit.

Underlying Model

The underlying architectural model is based on the following premises:

  * 
  * Every user-interface widget is associated with an X window. The X window ID
    for a widget is readily available from the widget. Standard Xlib calls can
    be used by widgets for many of their input and output operations.

  * 
  * The data for every widget is private to the widget and its subclasses. That
    is, the data is neither directly accessible nor visible outside of the
    module implementing the widget. All program interaction with the widget is
    performed by a set of operations (methods) that are defined for the widget.

  * 
  * Widget semantics are clearly separated from widget layout geometry. Widgets
    are concerned with implementing specific user-interface semantics. They
    have little control over issues such as their size or placement relative to
    other widget peers. Mechanisms are provided for associating geometric
    managers with widgets and for widgets to make suggestions about their own
    geometry.

Conventions Used in this Manual

  * All resources available to the widgets are listed with each widget. Many of
    these are available to more than one widget class due to the object
    oriented nature of the Intrinsics. The new resources for each widget are
    listed in bold text, and the inherited resources are listed in plain text.

  * Global symbols are printed in bold and can be function names, symbols
    defined in include files, or structure names. Arguments are printed in 
    italics.

  * Each function is introduced by a general discussion that distinguishes it
    from other functions. The function declaration itself follows, and each
    argument is specifically explained. General discussion of the function, if
    any is required, follows the arguments. Where applicable, the last
    paragraph of the explanation lists the return values of the function.

  * To eliminate any ambiguity between those arguments that you pass and those
    that a function returns to you, the explanations for all arguments that you
    pass start with the word specifies or, in the case of multiple arguments,
    the word specify. The explanations for all arguments that are returned to
    you start with the word returns or, in the case of multiple arguments, the
    word return. The explanations for all arguments that you can pass and are
    returned start with the words specifies and returns.

  * Any pointer to a structure that is used to return a value is designated as
    such by the _return suffix as part of its name. All other pointers passed
    to these functions are used for reading only. A few arguments use pointers
    to structures that are used for both input and output and are indicated by
    using the _in_out suffix.

Format of the Widget Reference Chapters

The majority of this document is a reference guide for the Athena widget set.
Chapters three through six give the programmer all information necessary to use
the widgets. The layout of the chapters follows a specific pattern to allow the
programmer to easily find the desired information.

The first few pages of every chapter give an overview of the widgets in that
section. Widgets are grouped into chapters by functionality.

"Chapter Simple Widgets

"Chapter Menus

"Chapter Text Widgets

"Chapter Composite and Constraint Widget

Following the introduction will be a description of each widget in that
chapter. When no functional grouping is obvious the widgets are listed in
alphabetical order, such as in chapters three and six.

The first section of each widget's description is a table that contains general
information about this widget class. Here is the table for the Box widget, and
an explanation of all the entries.




Application Header file <X11/Xaw/Box.h>
Class Header file       <X11/Xaw/BoxP.h>
Class           boxWidgetClass
Class Name      Box
Superclass      Composite


Application This file must be included when an application uses this widget. It
Header File usually contains the class definition, and some resource macros.
            This is often called the ``public'' header file.

Class       This file will only be used by widget programmers. It will need to
Header File be included by any widget that subclasses this widget. This is
            often called the ``private'' header file.

            This is the widget class of this widget. This global symbol is
Class       passed to XtCreateWidget so that the Intrinsics will know which
            type of widget to create.

Class Name  This is the resource name of this class. This name can be used in a
            resource file to match any widget of this class.

            This is the superclass that this widget class is descended from. If
Superclass  you understand how the superclass works it will allow you to more
            quickly understand what this widget does, since much of its
            functionality may be inherited from its superclass.

After this table follows a general description of the default behavior of this
widget, as seen by the user. In many cases this functionality may be overridden
by the application programmer, or by the user.

The next section is a table showing the name, class, type and default value of
each resource that is available to this widget. There is also a column
containing notes describing special restrictions placed upon individual
resources.

A This resource may be automatically adjusted when another resource is changed.

C This resource is only settable at widget creation time, and may not be
  modified with XtSetValues.

  Do not modify this resource. While setting this resource will work, it can
D cause unexpected behavior. When this symbol appears there is another,
  preferred, interface provided by the X Toolkit.

R This resource is READ-ONLY, and may not be modified.

After the resource table is a detailed description of every resource available
to that widget. Many of these are redundant, but printing them with each widget
saves page flipping. The names of the resources that are inherited are printed
in plain text, while the names of the resources that are new to this class are
printed in bold. If you have already read the description of the superclass you
need only pay attention to the resources printed in bold.

For each composite widget there is a section on layout semantics that follows
the resource description. This section will describe the effect of constraint
resources on the layout of the children, as well as a general description of
where it prefers to place its children.

Descriptions of default translations and action routines come next, for widgets
to which they apply. The last item in each widget's documentation is the
description of all convenience routines provided by the widget.

Input Focus

The Intrinsics define a resource on all Shell widgets that interact with the
window manager called input. This resource requests the assistance of window
manager in acquiring the input focus. The resource defaults to False in the
Intrinsics, but is redefined to default to True when an application is using
the Athena widget set. An application programmer may override this default and
set the resource back to False if the application does not need the window
manager to give it the input focus. See the X Toolkit Intrinsics - C Language
Interface for details on the input resource.

Chapter 2. Using Widgets

Table of Contents

Using Widgets

    Setting the Locale
    Initializing the Toolkit
    Creating a Widget
    Common Resources
    Resource Conversions
    Realizing a Widget
    Processing Events
    Standard Widget Manipulation Functions
    Using the Client Callback Interface
    Programming Considerations
    Example Programs

Using Widgets

Widgets serve as the primary tools for building a user interface or application
environment. The Athena widget set consists of primitive widgets that contain
no children (for example, a command button) and composite widgets which may
contain one or more widget children (for example, a Box widget).

The remaining chapters explain the widgets that are provided by the Athena
widget set. These user-interface components serve as an interface for
application programmers who do not want to implement their own widgets. In
addition, they serve as a starting point for those widget programmers who,
using the Intrinsics mechanisms, want to implement alternative application
programming interfaces.

This chapter is a brief introduction to widget programming. The examples
provided use the Athena widgets, though most of the concepts will apply to all
widget sets. Although there are several programming interfaces to the X
Toolkit, only one is described here. A full description of the programming
interface is provided in the document X Toolkit Intrinsics - C Language
Interface.

Setting the Locale

If it is desirable that the application take advantage of internationalization
(i18n), you must establish locale with XtSetLanguageProc before
XtDisplayInitialize or XtAppInitialize is called. For full details, please
refer to the document X Toolkit Intrinsics - C Language Interface, section 2.2.
However, the following simplest-case call is sufficient in many or most
applications.



        XtSetLanguageProc(NULL, NULL, NULL);

Most notably, this will affect the Standard C locale, determine which resource
files will be loaded, and what fonts will be required of FontSet
specifications. In many cases, the addition of this line is the only source
change required to internationalize Xaw programs, and will not disturb the
function of programs in the default "C" locale.

Initializing the Toolkit

You must call a toolkit initialization function before invoking any other
toolkit routines (besides locale setting, above). XtAppInitialize opens the X
server connection, parses the command line, and creates an initial widget that
will serve as the root of a tree of widgets created by this application.

Widget XtAppInitialize(XtAppContext app_context_return, String
application_class, XrmOptionDescRec options, Cardinal num_options, int
*argc_in_out, String *argv_in_out, String *fallback_resources, ArgList args,
Cardinal num_args);

app_con_return     Returns the application context of this application, if
                   non-NULL.

                   Specifies the class name of this application, which is
                   usually the generic name for all instances of this
application_class  application. A useful convention is to form the class name
                   by capitalizing the first letter of the application name.
                   For example, the application named ``xman'' has a class name
                   of ``Xman''.

                   Specifies how to parse the command line for any
options            application-specific resources. The options argument is
                   passed as a parameter to XrmParseCommand. For further
                   information, see Xlib - C Language Interface.

num_options        Specifies the number of entries in the options list.

argc_in_out        Specifies a pointer to the number of command line
                   parameters.

argv_in_out        Specifies the command line parameters.

fallback_resources Specifies resource values to be used if the site-wide
                   application class defaults file cannot be opened, or NULL.

args               Specifies the argument list to use when creating the
                   Application shell.

num_args           Specifies the number of arguments in args.

This function will remove the command line arguments that the toolkit reads
from argc_in_out, and argv_in_out. It will then attempt to open the display. If
the display cannot be opened, an error message is issued and XtAppInitialize
terminates the application. Once the display is opened, all resources are read
from the locations specified by the Intrinsics. This function returns an
ApplicationShell widget to be used as the root of the application's widget
tree.

Creating a Widget

Creating a widget is a three-step process. First, the widget instance is
allocated, and various instance-specific attributes are set by using
XtCreateWidget. Second, the widget's parent is informed of the new child by
using XtManageChild. Finally, X windows are created for the parent and all its
children by using XtRealizeWidget and specifying the top-most widget. The first
two steps can be combined by using XtCreateManagedWidget. In addition,
XtRealizeWidget is automatically called when the child becomes managed if the
parent is already realized.

To allocate, initialize, and manage a widget, use XtCreateManagedWidget .

Widget XtCreateManagedWidget(String name, WidgetClass widget_class, Widget
parent, ArgList args, Cardinal num_args);

name         Specifies the instance name for the created widget that is used
             for retrieving widget resources.

widget_class Specifies the widget class pointer for the created widget.

parent       Specifies the parent widget ID.

             Specifies the argument list. The argument list is a
args         variable-length list composed of name and value pairs that contain
             information pertaining to the specific widget instance being
             created. For further information, see Section 2.7.2.

num_args     Specifies the number of arguments in the argument list. If the
             num_args is zero, the argument list is never referenced.

When a widget instance is successfully created, the widget identifier is
returned to the application. If an error is encountered, the XtError routine is
invoked to inform the user of the error.

For further information, see X Toolkit Intrinsics - C Language Interface.

Common Resources

Although a widget can have unique arguments that it understands, all widgets
have common arguments that provide some regularity of operation. The common
arguments allow arbitrary widgets to be managed by higher-level components
without regard for the individual widget type. Widgets will ignore any argument
that they do not understand.

The following resources are retrieved from the argument list or from the
resource database by all of the Athena widgets:

+------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |   Default Value   |
|-----------------+-----------------+----------------+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|       NULL        |
|-----------------+-----------------+----------------+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |       True        |
|-----------------+-----------------+----------------+-------------------|
|   background    |   Background    |     Pixel      |XtDefaultBackground|
|-----------------+-----------------+----------------+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |XtDefaultForeground|
|-----------------+-----------------+----------------+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |         1         |
|-----------------+-----------------+----------------+-------------------|
|    colormap     |    Colormap     |    Colormap    | Parent's Colormap |
|-----------------+-----------------+----------------+-------------------|
|      depth      |      Depth      |      int       |  Parent's Depth   |
|-----------------+-----------------+----------------+-------------------|
| destroyCallback |    Callback     | XtCallbackList |       NULL        |
|-----------------+-----------------+----------------+-------------------|
|     height      |     Height      |   Dimension    | widget dependent  |
|-----------------+-----------------+----------------+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |       True        |
|-----------------+-----------------+----------------+-------------------|
|     screen      |     Screen      |     Screen     |  Parent's Screen  |
|-----------------+-----------------+----------------+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |       True        |
|-----------------+-----------------+----------------+-------------------|
|  translations   |  Translations   |TranslationTable| widget dependent  |
|-----------------+-----------------+----------------+-------------------|
|      width      |      Width      |   Dimension    | widget dependent  |
|-----------------+-----------------+----------------+-------------------|
|        x        |    Position     |    Position    |         0         |
|-----------------+-----------------+----------------+-------------------|
|        y        |    Position     |    Position    |         0         |
+------------------------------------------------------------------------+

The following additional resources are retrieved from the argument list or from
the resource database by many of the Athena widgets:

+----------------------------------------------------------------+
|      Name       |   Class   |     Type     |   Default Value   |
|-----------------+-----------+--------------+-------------------|
|    callback     | Callback  |XtCallbackList|       NULL        |
|-----------------+-----------+--------------+-------------------|
|     cursor      |  Cursor   |    Cursor    | widget dependent  |
|-----------------+-----------+--------------+-------------------|
|   foreground    |Foreground |    Pixel     |XtDefaultForeground|
|-----------------+-----------+--------------+-------------------|
|insensitiveBorder|Insensitive|    Pixmap    |    GreyPixmap     |
+----------------------------------------------------------------+

Resource Conversions

Most resources in the Athena widget set have a converter registered that will
translate the string in a resource file to the correct internal representation.
While some are obvious (string to integer, for example), others need specific
mention of the allowable values. Three general converters are described here:

  * Cursor

  * Pixel

  * Bitmap

Many widgets have defined special converters that apply only to that widget.
When these occur, the documentation section for that widget will describe the
converter.

Cursor Conversion

The value for the cursorName resource is specified in the resource database as
a string, and is of the following forms:

  * A standard X cursor name from < X11/cursorfont.h >. The names in
    cursorfont.h each describe a specific cursor. The resource names for these
    cursors are exactly like the names in this file except the XC_ is not used.
    The cursor definition XC_gumby has a resource name of gumby.

  * Glyphs, as in FONT font-name glyph-index [[ font-name ] glyph-index ]. The
    first font and glyph specify the cursor source pixmap. The second font and
    glyph specify the cursor mask pixmap. The mask font defaults to the source
    font, and the mask glyph index defaults to the source glyph index.

  * A relative or absolute file name. If a relative or absolute file name is
    specified, that file is used to create the source pixmap. Then the string
    "Mask" is appended to locate the cursor mask pixmap. If the "Mask" file
    does not exist, the suffix "msk" is tried. If "msk" fails, no cursor mask
    will be used. If the filename does not start with '/' or './' the the
    bitmap file path is used (see section 2.4.3).

Pixel Conversion

The string-to-pixel converter takes any name that is acceptable to XParseColor
(see Xlib - C Language Interface). In addition this routine understands the
special toolkit symbols `XtDefaultForeground' and `XtDefaultBackground',
described in X Toolkit Intrinsics - C Language Interface. In short the
acceptable pixel names are:

  * Any color name for the rgb.txt file (typically in the directory /usr/lib/
    X11 on POSIX systems).

  * A numeric specification of the form #<red><green><blue> where these numeric
    values are hexadecimal digits (both upper and lower case).

  * The special strings `XtDefaultForeground' and `XtDefaultBackground'

Bitmap Conversion

The string-to-bitmap converter attempts to locate a file containing bitmap data
whose name is specified by the input string. If the file name is relative (i.e.
does not begin with / or ./), the directories to be searched are specified in
the bitmapFilePath resource--class BitmapFilePath. This resource specifies a
colon (:) separated list of directories that will be searched for the named
bitmap or cursor glyph (see section 2.4.1). The bitmapFilePath resource is
global to the application, and may not be specified differently for each widget
that wishes to convert a cursor to bitmap. In addition to the directories
specified in the bitmapFilePath resource a default directory is searched. When
using POSIX the default directory is /usr/include/X11/bitmaps .

Realizing a Widget

The XtRealizeWidget function performs two tasks:

  * Calculates the geometry constraints of all managed descendants of this
    widget. The actual calculation is put off until realize time for
    performance reasons.

  * Creates an X window for the widget and, if it is a composite widget,
    realizes each of its managed children.

    void XtRealizeWidget(Widget w);

  * Specifies the widget.

For further information about this function, see the X Toolkit Intrinsics - C
Language Interface.

Processing Events

Now that the application has created, managed and realized its widgets, it is
ready to process the events that will be delivered by the X Server to this
client. A function call that will process the events is XtAppMainLoop.

void XtAppMainLoop(XtAppContext app_context);

app_context Specifies the application context of this application. The value is
            normally returned by XtAppInitialize.

This function never returns: it is an infinite loop that processes the X
events. User input can be handled through callback procedures and application
defined action routines. More details are provided in X Toolkit Intrinsics - C
Language Interface.

Standard Widget Manipulation Functions

After a widget has been created, a client can interact with that widget by
calling one of the standard widget manipulation routines provided by the
Intrinsics, or a widget class-specific manipulation routine.

The Intrinsics provide generic routines to give the application programmer
access to a set of standard widget functions. The common widget routines let an
application or composite widget perform the following operations on widgets
without requiring explicit knowledge of the widget type.

  * Control the mapping of widget windows

  * Destroy a widget instance

  * Obtain an argument value

  * Set an argument value

Mapping Widgets

By default, widget windows are mapped (made viewable) automatically by
XtRealizeWidget. This behavior can be disabled by using XtSetMappedWhenManaged,
making the client responsible for calling XtMapWidget to make the widget
viewable.

void XtSetMappedWhenManaged(Widget w, Boolean map_when_managed);

w                Specifies the widget.

                 Specifies the new value. If map_when_managed is True, the
                 widget is mapped automatically when it is realized. If
map_when_managed map_when_managed is False, the client must call XtMapWidget or
                 make a second call to XtSetMappedWhenManaged to cause the
                 child window to be mapped.

The definition for XtMapWidget is:

void XtMapWidget(Widget w);

w Specifies the widget.

When you are creating several children in sequence for a previously realized
common parent it is generally more efficient to construct a list of children as
they are created (using XtCreateWidget) and then use XtManageChildren to
request that their parent managed them all at once. By managing a list of
children at one time, the parent can avoid wasteful duplication of geometry
processing and the associated ``screen flash''.

void XtManageChildren(WidgetList children, Cardinal num_children);

children     Specifies a list of children to add.

num_children Specifies the number of children to add.

If the parent is already visible on the screen, it is especially important to
batch updates so that the minimum amount of visible window reconfiguration is
performed.

For further information about these functions, see the X Toolkit Intrinsics - C
Language Interface.

Destroying Widgets

To destroy a widget instance of any type, use XtDestroyWidget

void XtDestroyWidget(Widget w);

w Specifies the widget.

XtDestroyWidget destroys the widget and recursively destroys any children that
it may have, including the windows created by its children. After calling
XtDestroyWidget , no further references should be made to the widget or any
children that the destroyed widget may have had.

Retrieving Widget Resource Values

To retrieve the current value of a resource attribute associated with a widget
instance, use XtGetValues .

void XtGetValues(Widget w, ArgList args, Cardinal num_args);

w        Specifies the widget.

         Specifies a variable-length argument list of name and address pairs
args     that contain the resource name and the address into which the resource
         value is stored.

num_args Specifies the number of arguments in the argument list.

The arguments and values passed in the argument list are dependent on the
widget. Note that the caller is responsible for providing space into which the
returned resource value is copied; the ArgList contains a pointer to this
storage (e.g. x and y must be allocated as Position). For further information,
see the X Toolkit Intrinsics - C Language Interface.

Modifying Widget Resource Values

To modify the current value of a resource attribute associated with a widget
instance, use XtSetValues .

void XtSetValues(Widget w, ArgList args, Cardinal num_args);

w        Specifies the widget.

args     Specifies an array of name and value pairs that contain the arguments
         to be modified and their new values.

num_args Specifies the number of arguments in the argument list.

The arguments and values that are passed will depend on the widget being
modified. Some widgets may not allow certain resources to be modified after the
widget instance has been created or realized. No notification is given if any
part of a XtSetValues request is ignored.

For further information about these functions, see the X Toolkit Intrinsics - C
Language Interface. The argument list entry for XtGetValues specifies the
address to which the caller wants the value copied. The argument list entry for
XtSetValues , however, contains the new value itself, if the size of value is
less than sizeof(XtArgVal) (architecture dependent, but at least sizeof(long));
otherwise, it is a pointer to the value. String resources are always passed as
pointers, regardless of the length of the string.

Using the Client Callback Interface

Widgets can communicate changes in their state to their clients by means of a
callback facility. The format for a client's callback handler is:

void CallbackProc(Widget w, XtPointer client_data, XtPointer call_data);

w           Specifies widget for which the callback is registered.

            Specifies arbitrary client-supplied data that the widget should
            pass back to the client when the widget executes the client's
            callback procedure. This is a way for the client registering the
client_data callback to also register client-specific data: a pointer to
            additional information about the widget, a reason for invoking the
            callback, and so on. If no additional information is necessary,
            NULL may be passed as this argument. This field is also frequently
            known as the closure.

            Specifies any callback-specific data the widget wants to pass to
call_data   the client. For example, when Scrollbar executes its jumpProc
            callback list, it passes the current position of the thumb in 
            call_data.

Callbacks can be registered either by creating an argument containing the
callback list described below or by using the special convenience routines
XtAddCallback and XtAddCallbacks. When the widget is created, a pointer to a
list of callback procedure and data pairs can be passed in the argument list to
XtCreateWidget . The list is of type XtCallbackList :



typedef struct {
        XtCallbackProc callback;
        XtPointer closure;
} XtCallbackRec, *XtCallbackList;

The callback list must be allocated and initialized before calling
XtCreateWidget . The end of the list is identified by an entry containing NULL
in callback and closure. Once the widget is created, the client can change or
de-allocate this list; the widget itself makes no further reference to it. The
closure field contains the client_data passed to the callback when the callback
list is executed.

The second method for registering callbacks is to use XtAddCallback after the
widget has been created.

void XtAddCallback(Widget w, String callback_name, XtCallbackProc callback,
XtPointer client_data);

w             Specifies the widget to add the callback to.

callback_name Specifies the callback list within the widget to append to.

callback      Specifies the callback procedure to add.

client_data   Specifies the data to be passed to the callback when it is
              invoked.

XtAddCallback adds the specified callback to the list for the named widget.

All widgets provide a callback list named destroyCallback where clients can
register procedures that are to be executed when the widget is destroyed. The
destroy callbacks are executed when the widget or an ancestor is destroyed. The
call_data argument is unused for destroy callbacks.

Programming Considerations

This section provides some guidelines on how to set up an application program
that uses the X Toolkit.

Writing Applications

When writing an application that uses the X Toolkit, you should make sure that
your application performs the following:

 1. Include < X11/Intrinsic.h > in your application programs. This header file
    automatically includes < X11/Xlib.h >, so all Xlib functions also are
    defined. It may also be necessary to include < X11/StringDefs.h > when
    setting up argument lists, as many of the XtNsomething definitions are only
    defined in this file.

 2. Include the widget-specific header files for each widget type that you need
    to use. For example, < X11/Xaw/Label.h > and < X11/Xaw/Command.h >.

 3. Call the XtAppInitialize function before invoking any other toolkit or Xlib
    functions. For further information, see Section 2.1 and the X Toolkit
    Intrinsics - C Language Interface.

 4. To pass attributes to the widget creation routines that will override any
    site or user customizations, set up argument lists. In this document, a
    list of valid argument names is provided in the discussion of each widget.
    The names each have a global symbol defined that begins with XtN to help
    catch spelling errors. For example, XtNlabel is defined for the label
    resource of many widgets.

 5. For further information, see Section 2.9.2.2.

 6. When the argument list is set up, create the widget with the
    XtCreateManagedWidget function. For further information, see Section 2.2
    and the X Toolkit Intrinsics - C Language Interface.

 7. If the widget has any callback routines, set by the XtNcallback argument or
    the XtAddCallback function, declare these routines within the application.

 8. After creating the initial widget hierarchy, windows must be created for
    each widget by calling XtRealizeWidget on the top level widget.

 9. Most applications now sit in a loop processing events using XtAppMainLoop ,
    for example:

10.
    XtCreateManagedWidget(name, class, parent, args, num_args);
    XtRealizeWidget(shell);
    XtAppMainLoop(app_context);

11. For information about this function, see the X Toolkit Intrinsics - C
    Language Interface.

12. Link your application with libXaw (the Athena widgets), libXmu
    (miscellaneous utilities), libXt (the X Toolkit Intrinsics), libSM (Session
    Management), libICE (Inter-Client Exchange), libXext (the extension library
    needed for the shape extension code which allows rounded Command buttons),
    and libX11 (the core X library). The following provides a sample command
    line:

13.
    cc -o application application.c \-lXaw \-lXmu \-lXt \
    \-lSM \-lICE \-lXext \-lX11

Changing Resource Values

The Intrinsics support two methods of changing the default resource values; the
resource manager, and an argument list passed into XtCreateWidget. While
resources values will get updated no matter which method you use, the two
methods provide slightly different functionality.

         This method picks up resource definitions described in Xlib - C
         Language Interface from many different locations at run time. The
         locations most important to the application programmer are the 
         fallback resources and the app-defaults file, (see X Toolkit
Resource Intrinsics - C Language Interface for the complete list). Since these
Manager  resource are loaded at run time, they can be overridden by the user,
         allowing an application to be customized to fit the particular needs
         of each individual user. These values can also be modified without the
         need to rebuild the application, allowing rapid prototyping of user
         interfaces. Application programmers should use resources in preference
         to hard-coded values whenever possible.

         The values passed into the widget at creation time via an argument
Argument list cannot be modified by the user, and allow no opportunity for
Lists    customization. It is used to set resources that cannot be specified as
         strings (e.g. callback lists) or resources that should not be
         overridden (e.g. window depth) by the user.

Specifying Resources

It is important for all X Toolkit application programmers to understand how to
use the X Resource Manager to specify resources for widgets in an X
application. This section will describe the most common methods used to specify
these resources, and how to use the X Resource manager.

            The xrdb utility may be used to load a file containing resources
Xrdb        into the X server. Once the resources are loaded, the resources
            will affect any new applications started on the display that they
            were loaded onto.

Application The application defaults (app-defaults) file (normally in /usr/lib/
Defaults    X11/app-defaults/classname) for an application is loaded whenever
            the application is started.

The resource specification has two colon-separated parts, a name, and a value.
The value is a string whose format is dependent on the resource specified by 
name. Name is constructed by appending a resource name to a full widget name.

The full widget name is a list of the name of every ancestor of the desired
widget separated by periods (.). Each widget also has a class associated with
it. A class is a type of widget (e.g. Label or Scrollbar or Box). Notice that
class names, by convention, begin with capital letters and instance names begin
with lower case letters. The class of any widget may be used in place of its
name in a resource specification. Here are a few examples:

                  This is a fully specified resource name, and will affect only
                  widgets called button1 that are children of widgets called
xman.form.button1 form that are children of applications named xman. (Note that
                  while typically two widgets that are siblings will have
                  different names, it is not prohibited.)

                  This will match any Command widget that is a child of a Form
Xman.Form.Command widget that is itself a child of an application of class Xman
                  .

Xman.Form.button1 This is a mixed resource name with both widget names and
                  classes specified.

This syntax allows an application programmer to specify any widget in the
widget tree. To match more than one widget (for example a user may want to make
all Command buttons blue), use an asterisk (*) instead of a period. When an
asterisk is used, any number of widgets (including zero) may exist between the
two widget names. For example:

Xman*Command This matches all Command widgets in the Xman application.

Foo*button1  This matches any widget in the Foo application that is named 
             button1.

The root of all application widget trees is the widget returned by
XtAppInitialize. Even though this is actually an ApplicationShell widget, the
toolkit replaces its widget class with the class name of the application. The
name of this widget is either the name used to invoke the application (argv[0])
or the name of the application specified using the standard -name command line
option supported by the Intrinsics.

The last step in constructing the resource name is to append the name of the
resource with either a period or asterisk to the full or partial widget name
already constructed.

*foreground:Blue                Specifies that all widgets in all applications
                                will have a foreground color of blue.

                                Specifies that all widgets in an application
Xman*borderWidth:10             whose class is Xman will have a border width of
                                10 (pixels).

xman.form.button1.label:Testing Specifies that a particular widget in the xman
                                application will have a label named Testing.

An exclamation point (!) in the first column of a line indicates that the rest
of the line should be treated as a comment.

Final Words

The Resource manager is a powerful tool that can be used very effectively to
customize X Toolkit applications at run time by either the application
programmer or the user. Some final points to note:

  * An application programmer may add new resources to their application. These
    resources are associated with the global application, and not any
    particular widget. The X Toolkit function used for adding the application
    resources is XtGetApplicationResources.

  * Be careful when creating resource files. Since widgets will ignore
    resources that they do not understand, any spelling errors will cause a
    resource to have no effect.

  * Only one resource line will match any given resource. There is a set of
    precedence rules, which take the following general stance.

  * 
      + More specific overrides less specific, thus period always overrides
        asterisk.

      + Names on the left are more specific and override names on the right.

      + When resource specifications are exactly the same, user defaults will
        override program defaults.

For a complete explanation of the rules of precedence, and other specific
topics see X Toolkit Intrinsics - C Language Interface and Xlib - C Language
Interface.

Creating Argument Lists

To set up an argument list for the inline specification of widget attributes,
you may use any of the four approaches discussed in this section. Each resource
name has a global symbol associated with it. This global symbol has the form
XtNresource name. For example, the symbol for ``foreground'' is XtNforeground.
For further information, see the X Toolkit Intrinsics - C Language Interface.

Argument are specified by using the following structure:



typedef struct {
        String name;
        XtArgVal value;
} Arg, *ArgList;

The first approach is to statically initialize the argument list. For example:



static Arg arglist[] = {
        {XtNwidth, (XtArgVal) 400},
        {XtNheight, (XtArgVal) 300},
};

This approach is convenient for lists that do not need to be computed at
runtime and makes adding or deleting new elements easy. The XtNumber macro is
used to compute the number of elements in the argument list, preventing simple
programming errors:

XtCreateWidget(name, class, parent, arglist, XtNumber(arglist));

The second approach is to use the XtSetArg macro. For example:



Arg arglist[10];
XtSetArg(arglist[1], XtNwidth, 400);
XtSetArg(arglist[2], XtNheight, 300);

To make it easier to insert and delete entries, you also can use a variable
index:



Arg arglist[10];
Cardinal i=0;
XtSetArg(arglist[i], XtNwidth,  400);       i++;
XtSetArg(arglist[i], XtNheight, 300);       i++;

The i variable can then be used as the argument list count in the widget create
function. In this example, XtNumber would return 10, not 2, and therefore is
not useful. You should not use auto-increment or auto-decrement within the
first argument to XtSetArg . As it is currently implemented, XtSetArg is a
macro that dereferences the first argument twice.

The third approach is to individually set the elements of the argument list
array:



Arg arglist[10];
arglist[0].name  = XtNwidth;
arglist[0].value = (XtArgVal) 400;
arglist[1].name  = XtNheight;
arglist[1].value = (XtArgVal) 300;

Note that in this example, as in the previous example, XtNumber would return
10, not 2, and therefore would not be useful.

The fourth approach is to use a mixture of the first and third approaches: you
can statically define the argument list but modify some entries at runtime. For
example:



static Arg arglist[] = {
        {XtNwidth, (XtArgVal) 400},
        {XtNheight, (XtArgVal) NULL},
};
arglist[1].value = (XtArgVal) 300;

In this example, XtNumber can be used, as in the first approach, for easier
code maintenance.

Example Programs

The best way to understand how to use any programming library is by trying some
simple examples. A collection of example programs that introduces each of the
widgets in that Athena widget set, as well as many important toolkit
programming concepts, is available in the X11R5 contrib release as distributed
by the X Consortium. It can be found in the directory contrib/examples/Xaw in
the archive at http://www.x.org/releases/X11R5/contrib-1.tar.Z See the README
file from that directory for a guide to the examples.

Chapter 3. Simple Widgets

Table of Contents

Command Widget

    Resources
    Command Actions

Grip Widget

    Resources
    Grip Actions

Label Widget

    Resources

List Widget

    Resources
    List Actions
    List Callbacks
    Changing the List
    Highlighting an Item
    Unhighlighting an Item
    Retrieving the Currently Selected Item
    Restrictions

Panner Widget

    Resources
    Panner Actions
    Panner Callbacks

Repeater Widget

    Resources
    Repeater Actions

Scrollbar Widget

    Resources
    Scrollbar Actions
    Scrollbar Callbacks
    Convenience Routines
    Setting Float Resources

Simple Widget

    Resources

StripChart Widget

    Resources
    Getting the StripChart Value

Toggle Widget

    Resources
    Toggle Actions
    Toggle Actions
    Radio Groups
    Convenience Routines

Each of these widgets performs a specific user interface function. They are 
simple because they cannot have widget children\(emthey may only be used as
leaves of the widget tree. These widgets display information or take user
input.

           A push button that, when selected, may cause a specific action to
Command    take place. This widget can display a multi-line string or a bitmap
           or pixmap image.

Grip       A rectangle that, when selected, will cause an action to take place.

Label      A rectangle that can display a multi-line string or a bitmap or
           pixmap image.

           A list of text strings presented in row column format that may be
List       individually selected. When an element is selected an action may
           take place.

Panner     A rectangular area containing a slider that may be moved in two
           dimensions. Notification of movement may be continuous or discrete.

           A push button that triggers an action at an increasing rate when
Repeater   selected. This widget can display a multi-line string or a bitmap or
           pixmap image.

           A rectangular area containing a thumb that when slid along one
Scrollbar  dimension may cause a specific action to take place. The Scrollbar
           may be oriented horizontally or vertically.

Simple     The base class for most of the simple widgets. Provides a
           rectangular area with a settable mouse cursor and special border.

StripChart A real time data graph that will automatically update and scroll.

           A push button that contains state information. Toggles may also be
Toggle     used as "radio buttons" to implement a "one of many" or "zero or one
           of many" group of buttons. This widget can display a multi-line
           string or a bitmap or pixmap image.

Command Widget




Application header file <X11/Xaw/Command.h>

Class header file       <X11/Xaw/CommandP.h>

Class   commandWidgetClass

Class Name      Command

Superclass      Label


The Command widget is an area, often rectangular, that contains text or a
graphical image. Command widgets are often referred to as ``push buttons.''
When the pointer is over a Command widget, the widget becomes highlighted by
drawing a rectangle around its perimeter. This highlighting indicates that the
widget is ready for selection. When mouse button 1 is pressed, the Command
widget indicates that it has been selected by reversing its foreground and
background colors. When the mouse button is released, the Command widget's
notify action is invoked, calling all functions on its callback list. If the
pointer is moved off of the widget before the pointer button is released, the
widget reverts to its normal foreground and background colors, and releasing
the pointer button has no effect. This behavior allows the user to cancel an
action.

Resources

When creating a Command widget instance, the following resources are retrieved
from the argument list or from the resource database:

+------------------------------------------------------------------------------------+
|         Name         |      Class       |      Type      |Notes|   Default Value   |
|----------------------+------------------+----------------+-----+-------------------|
|     accelerators     |   Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive |    Boolean     |  D  |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|      background      |    Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+------------------+----------------+-----+-------------------|
|   backgroundPixmap   |      Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+------------------+----------------+-----+-------------------|
|        bitmap        |      Bitmap      |     Pixmap     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|     borderPixmap     |      Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+------------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth    |   Dimension    |     |         1         |
|----------------------+------------------+----------------+-----+-------------------|
|       callback       |     Callback     | XtCallbackList |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|       colormap       |     Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+------------------+----------------+-----+-------------------|
|  cornerRoundPercent  |CornerRoundPercent|   Dimension    |     |        25         |
|----------------------+------------------+----------------+-----+-------------------|
|        cursor        |      Cursor      |     Cursor     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|      cursorName      |      Cursor      |     String     |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|        depth         |      Depth       |      int       |  C  |  Parent's Depth   |
|----------------------+------------------+----------------+-----+-------------------|
|   destroyCallback    |     Callback     | XtCallbackList |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|       encoding       |     Encoding     |  UnsignedChar  |     |XawTextEncoding8bit|
|----------------------+------------------+----------------+-----+-------------------|
|         font         |       Font       |  XFontStruct   |     |   XtDefaultFont   |
|----------------------+------------------+----------------+-----+-------------------|
|      foreground      |    Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|        height        |      Height      |   Dimension    |  A  |graphic height + 2 |
|                      |                  |                |     | * internalHeight  |
|----------------------+------------------+----------------+-----+-------------------|
|  highlightThickness  |    Thickness     |   Dimension    |  A  |  2 (0 if Shaped)  |
|----------------------+------------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive    |     Pixmap     |     |    GreyPixmap     |
|----------------------+------------------+----------------+-----+-------------------|
|    internalHeight    |      Height      |   Dimension    |     |         2         |
|----------------------+------------------+----------------+-----+-------------------|
|    internalWidth     |      Width       |   Dimension    |     |         4         |
|----------------------+------------------+----------------+-----+-------------------|
|    international     |  International   |    Boolean     |  C  |       False       |
|----------------------+------------------+----------------+-----+-------------------|
|       justify        |     Justify      |    Justify     |     |  XtJustifyCenter  |
|                      |                  |                |     |     (center)      |
|----------------------+------------------+----------------+-----+-------------------|
|        label         |      Label       |     String     |     |  name of widget   |
|----------------------+------------------+----------------+-----+-------------------|
|      leftBitmap      |    LeftBitmap    |     Bitmap     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|     pointerColor     |    Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|pointerColorBackground|    Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+------------------+----------------+-----+-------------------|
|        resize        |      Resize      |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|        screen        |      Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+------------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive     |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|      shapeStyle      |    ShapeStyle    |   ShapeStyle   |     |     Rectangle     |
|----------------------+------------------+----------------+-----+-------------------|
|     translations     |   Translations   |TranslationTable|     |     See below     |
|----------------------+------------------+----------------+-----+-------------------|
|        width         |      Width       |   Dimension    |  A  |graphic width + 2 *|
|                      |                  |                |     |   internalWidth   |
|----------------------+------------------+----------------+-----+-------------------|
|          x           |     Position     |    Position    |     |         0         |
|----------------------+------------------+----------------+-----+-------------------|
|          y           |     Position     |    Position    |     |         0         |
|----------------------+------------------+----------------+-----+-------------------|
|          _           |                  |                |     |                   |
+------------------------------------------------------------------------------------+

\" Resource Descriptions

Command Actions

The Command widget supports the following actions:

  * Switching the button's interior between the foreground and background
    colors with set, unset, and reset.

  * Processing application callbacks with notify

  * Switching the internal border between highlighted and unhighlighted states
    with highlight and unhighlight

The following are the default translation bindings used by the Command widget:



        <EnterWindow>:  highlight(\|)
        <LeaveWindow>:  reset(\|)
        <Btn1Down>:     set(\|)
        <Btn1Up>:       notify(\|) unset(\|)

The full list of actions supported by Command is:

            Displays the internal highlight border in the color (foreground or
highlight   background ) that contrasts with the interior color of the Command
(condition) widget. The conditions WhenUnset and Always are understood by this
            action procedure. If no argument is passed, WhenUnset is assumed.

unhighlight Displays the internal highlight border in the color (foreground or
(\|)        background ) that matches the interior color of the Command widget.

            Enters the set state, in which notify is possible. This action
set(\|)     causes the button to display its interior in the foreground color.
            The label or bitmap is displayed in the background color.

            Cancels the set state and displays the interior of the button in
unset(\|)   the background color. The label or bitmap is displayed in the
            foreground color.

            Cancels any set or highlight and displays the interior of the
reset(\|)   button in the background color, with the label or bitmap displayed
            in the foreground color.

            When the button is in the set state this action calls all functions
notify(\|)  in the callback list named by the callback resource. The value of
            the call_data argument passed to these functions is undefined.

A very common alternative to registering callbacks is to augment a Command's
translations with an action performing the desired function. This often takes
the form of:



*Myapp*save.translations: #augment <Btn1Down>,<Btn1Up>: Save()

When a bitmap of depth greater that one (1) is specified the set(), unset(),
and reset() actions have no effect, since there are no foreground and
background colors used in a multi-plane pixmap.

Grip Widget




Application header file <X11/Xaw/Grip.h>

Class header file       <X11/Xaw/GripP.h>

Class   gripWidgetClass

Class Name      Grip

Superclass      Simple


The Grip widget provides a small rectangular region in which user input events
(such as ButtonPress or ButtonRelease) may be handled. The most common use for
the Grip widget is as an attachment point for visually repositioning an object,
such as the pane border in a Paned widget.

Resources

When creating a Grip widget instance, the following resources are retrieved
from the argument list or from the resource database:

+-----------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value   |
|----------------------+-----------------+----------------+-----+-------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|       callback       |    Callback     |    Callback    |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|       colormap       |    Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+-----------------+----------------+-----+-------------------|
|        cursor        |     Cursor      |     Cursor     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|      cursorName      |     Cursor      |     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|----------------------+-----------------+----------------+-----+-------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|      foreground      |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|        height        |     Height      |   Dimension    |     |         8         |
|----------------------+-----------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |     Pixmap     |     |    GreyPixmap     |
|----------------------+-----------------+----------------+-----+-------------------|
|    international     |  International  |    Boolean     |  C  |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|        screen        |     Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+-----------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     translations     |  Translations   |TranslationTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        width         |      Width      |   Dimension    |     |         8         |
|----------------------+-----------------+----------------+-----+-------------------|
|          x           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          y           |    Position     |    Position    |     |         0         |
+-----------------------------------------------------------------------------------+

           All routines on this list are called whenever the GripAction action
callback   routine is invoked. The call_data contains all information passed to
           the action routine. A detailed description is given below in the
           Grip Actions section.

foreground A pixel value which indexes the widget's colormap to derive the
           color used to flood fill the entire Grip widget.

Grip Actions

The Grip widget does not declare any default event translation bindings, but it
does declare a single action routine named GripAction. The client specifies an
arbitrary event translation table, optionally giving parameters to the
GripAction routine.

The GripAction routine executes the callbacks on the callback list, passing as
call_data a pointer to a XawGripCallData structure, defined in the Grip
widget's application header file.






typedef struct _XawGripCallData {
        XEvent *event;
        String *params;
        Cardinal num_params;
} XawGripCallDataRec, *XawGripCallData,
  GripCallDataRec, *GripCallData; /* supported for R4 compatibility */





In this structure, the event is a pointer to the input event that triggered the
action. params and num_params give the string parameters specified in the
translation table for the particular event binding.

The following is an example of a translation table that uses the GripAction:




        <Btn1Down>:     GripAction(press)
        <Btn1Motion>:   GripAction(move)
        <Btn1Up>:       GripAction(release)


For a complete description of the format of translation tables, see the X
Toolkit Intrinsics - C Language Interface.

Label Widget




Application header file <X11/Xaw/Label.h>

Class header file       <X11/Xaw/LabelP.h>

Class   labelWidgetClass

Class Name      Label

Superclass      Simple


A Label widget holds a graphic displayed within a rectangular region of the
screen. The graphic may be a text string containing multiple lines of
characters in an 8 bit or 16 bit character set (to be displayed with a font),
or in a multi-byte encoding (for use with a fontset). The graphic may also be a
bitmap or pixmap. The Label widget will allow its graphic to be left, right, or
center justified. Normally, this widget can be neither selected nor directly
edited by the user. It is intended for use as an output device only.

Resources

When creating a Label widget instance, the following resources are retrieved
from the argument list or from the resource database:

+-----------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value   |
|----------------------+-----------------+----------------+-----+-------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|        bitmap        |     Bitmap      |     Pixmap     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         1         |
|----------------------+-----------------+----------------+-----+-------------------|
|       colormap       |    Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+-----------------+----------------+-----+-------------------|
|        cursor        |     Cursor      |     Cursor     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|      cursorName      |     Cursor      |     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|----------------------+-----------------+----------------+-----+-------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|       encoding       |    Encoding     |  UnsignedChar  |     |XawTextEncoding8bit|
|----------------------+-----------------+----------------+-----+-------------------|
|         font         |      Font       |  XFontStruct   |     |   XtDefaultFont   |
|----------------------+-----------------+----------------+-----+-------------------|
|       fontSet        |     FontSet     |    XFontSet    |     | XtDefaultFontSet  |
|----------------------+-----------------+----------------+-----+-------------------|
|      foreground      |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|        height        |     Height      |   Dimension    |  A  |graphic height + 2 |
|                      |                 |                |     | * internalHeight  |
|----------------------+-----------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |     Pixmap     |     |    GreyPixmap     |
|----------------------+-----------------+----------------+-----+-------------------|
|    internalHeight    |     Height      |   Dimension    |     |         2         |
|----------------------+-----------------+----------------+-----+-------------------|
|    internalWidth     |      Width      |   Dimension    |     |         4         |
|----------------------+-----------------+----------------+-----+-------------------|
|    international     |  International  |    Boolean     |  C  |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|       justify        |     Justify     |    Justify     |     |  XtJustifyCenter  |
|                      |                 |                |     |     (center)      |
|----------------------+-----------------+----------------+-----+-------------------|
|        label         |      Label      |     String     |     |  name of widget   |
|----------------------+-----------------+----------------+-----+-------------------|
|      leftBitmap      |   LeftBitmap    |     Bitmap     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|        resize        |     Resize      |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|        screen        |     Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+-----------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     translations     |  Translations   |TranslationTable|     |     See above     |
|----------------------+-----------------+----------------+-----+-------------------|
|        width         |      Width      |   Dimension    |  A  |graphic width + 2 *|
|                      |                 |                |     |   internalWidth   |
|----------------------+-----------------+----------------+-----+-------------------|
|          x           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          y           |    Position     |    Position    |     |         0         |
+-----------------------------------------------------------------------------------+

List Widget




Application header file <X11/Xaw/List.h>

Class header file       <X11/Xaw/ListP.h>

Class   listWidgetClass

Class Name      List

Superclass      Simple


The List widget contains a list of strings formatted into rows and columns.
When one of the strings is selected, it is highlighted, and the List widget's
Notify action is invoked, calling all routines on its callback list. Only one
string may be selected at a time.

Resources

When creating a List widget instance, the following resources are retrieved
from the argument list or from the resource database:

+-----------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value   |
|----------------------+-----------------+----------------+-----+-------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         1         |
|----------------------+-----------------+----------------+-----+-------------------|
|       callback       |    Callback     |    Callback    |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|       colormap       |    Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+-----------------+----------------+-----+-------------------|
|    columnSpacing     |     Spacing     |   Dimension    |     |         6         |
|----------------------+-----------------+----------------+-----+-------------------|
|        cursor        |     Cursor      |     Cursor     |     |    XC_left_ptr    |
|----------------------+-----------------+----------------+-----+-------------------|
|      cursorName      |     Cursor      |     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|    defaultColumns    |     Columns     |      int       |     |         2         |
|----------------------+-----------------+----------------+-----+-------------------|
|        depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|----------------------+-----------------+----------------+-----+-------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|         font         |      Font       |   FontStruct   |     |   XtDefaultFont   |
|----------------------+-----------------+----------------+-----+-------------------|
|       fontSet        |     FontSet     |    XFontSet    |     | XtDefaultFontSet  |
|----------------------+-----------------+----------------+-----+-------------------|
|     forceColumns     |     Columns     |    Boolean     |     |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|      foreground      |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|        height        |     Height      |   Dimension    |  A  |  Enough space to  |
|                      |                 |                |     | contain the list  |
|----------------------+-----------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |     Pixmap     |     |    GreyPixmap     |
|----------------------+-----------------+----------------+-----+-------------------|
|    internalHeight    |     Height      |   Dimension    |     |         2         |
|----------------------+-----------------+----------------+-----+-------------------|
|    internalWidth     |      Width      |   Dimension    |     |         4         |
|----------------------+-----------------+----------------+-----+-------------------|
|    international     |  International  |    Boolean     |  C  |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|         list         |      List       |    Pointer     |     |  name of widget   |
|----------------------+-----------------+----------------+-----+-------------------|
|       longest        |     Longest     |      int       |  A  |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|    numberStrings     |  NumberStrings  |      int       |  A  | computed for NULL |
|                      |                 |                |     |  terminated list  |
|----------------------+-----------------+----------------+-----+-------------------|
|     pasteBuffer      |     Boolean     |    Boolean     |     |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|      rowSpacing      |     Spacing     |   Dimension    |     |         2         |
|----------------------+-----------------+----------------+-----+-------------------|
|        screen        |     Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+-----------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     translations     |  Translations   |TranslationTable|     |     See below     |
|----------------------+-----------------+----------------+-----+-------------------|
|     verticalList     |     Boolean     |    Boolean     |     |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|        width         |      Width      |   Dimension    |  A  |  Enough space to  |
|                      |                 |                |     | contain the list  |
|----------------------+-----------------+----------------+-----+-------------------|
|          x           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          y           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          _           |                 |                |     |                   |
+-----------------------------------------------------------------------------------+

                 All functions on this list are called whenever the notify
callback         action is invoked. The call_data argument contains information
                 about the element selected and is described in detail in the
                 List Callbacks section.

columnSpacing

rowSpacing       The amount of space, in pixels, between each of the rows and
                 columns in the list.

                 The default number of columns. This value is used when neither
defaultColumns   the width nor the height of the List widget is specified or
                 when forceColumns is True.

font             The text font to use when displaying the list, when the
                 international resource is false.

fontSet          The text font set to use when displaying the list, when the
                 international resource is true.

forceColumns     Forces the default number of columns to be used regardless of
                 the List widget's current size.

foreground       A pixel value which indexes the widget's colormap to derive
                 the color used to paint the text of the list elements.

\
fPinternalHeight
\fP

\fPinternalWidth The margin, in pixels, between the edges of the list and the
\fP              corresponding edge of the List widget's window.

                 An array of text strings displayed in the List widget. If
                 numberStrings is zero (the default) then the list must be NULL
                 terminated. If a value is not specified for the list, then
list             numberStrings is set to 1, and the name of the widget is used
                 as the list, and longest is set to the length of the name of
                 the widget. The list is used in place, and must be available
                 to the List widget for the lifetime of this widget, or until
                 it is changed with XtSetValues or XawListChange.

                 Specifies the width, in pixels, of the longest string in the
longest          current list. The List widget will compute this value if zero
                 (the default) is specified. If this resource is set by hand,
                 entries longer than this will be clipped to fit.

                 The number of strings in the current list. If a value of zero
numberStrings    (the default) is specified, the List widget will compute it.
                 When computing the number of strings the List widget assumes
                 that the list is NULL terminated.

pasteBuffer      If this resource is set to True then the name of the currently
                 selected list element will be put into CUT_BUFFER_0.

verticalList     If this resource is set to True then the list elements will be
                 presented in column major order.

List Actions

The List widget supports the following actions:

  * Highlighting and unhighlighting the list element under the pointer with Set
    and Unset

  * Processing application callbacks with Notify

The following is the default translation table used by the List Widget:



<Btn1Down>,<Btn1Up>:    Set(\|) Notify(\|)


The full list of actions supported by List widget is:

       Sets the list element that is currently under the pointer. To inform the
Set(\  user that this element is currently set, it is drawn with foreground and
|)     background colors reversed. If this action is called when there is no
       list element under the cursor, the currently set element will be unset.

Unset  Cancels the set state of the element under the pointer, and redraws it
(\|)   with normal foreground and background colors.

Notify Calls all callbacks on the List widget's callback list. Information
(\|)   about the currently selected list element is passed in the call_data
       argument (see List Callbacks below).

List Callbacks

All procedures on the List widget's callback list will have a
XawListReturnStruct passed to them as call_data. The structure is defined in
the List widget's application header file.




typedef struct _XawListReturnStruct {
        String string;  /* string shown in the list. */
        int list_index; /* index of the item selected. */
} XawListReturnStruct;



Note

The list_index item used to be called simply index. Unfortunately, this name
collided with a global name defined on some operating systems, and had to be
changed.

Changing the List

To change the list that is displayed, use XawListChange .

void XawListChange(Widget w, String* list, intnitems, longest, Boolean resize);

w       Specifies the List widget.

list    Specifies the new list for the List widget to display.

        Specifies the number of items in the list. If a value less than 1 is
nitems  specified, list must be NULL terminated, and the number of items will
        be calculated by the List widget.

        Specifies the length of the longest item in the list in pixels. If a
longest value less than 1 is specified, the List widget will calculate the
        value.

        Specifies a Boolean value that if True indicates that the List widget
resize  should try to resize itself after making the change. The constraints of
        the List widget's parent are always enforced, regardless of the value
        specified here.

XawListChange will unset all list elements that are currently set before the
list is actually changed. The list is used in place, and must remain usable for
the lifetime of the List widget, or until list has been changed again with this
function or with XtSetValues.

Highlighting an Item

To highlight an item in the list, use XawListHighlight .

void XawListHighlight(Widget w, int item);

w    Specifies the List widget.

item Specifies an index into the current list that indicates the item to be
     highlighted.

Only one item can be highlighted at a time. If an item is already highlighted
when XawListHighlight is called, the highlighted item is unhighlighted before
the new item is highlighted.

Unhighlighting an Item

To unhighlight the currently highlighted item in the list, use
XawListUnhighlight .

void XawListUnhighlight(Widget w);

w Specifies the List widget.

Retrieving the Currently Selected Item

To retrieve the list element that is currently set, use XawListShowCurrent .

XawListReturnStruct *XawListShowCurrent(Widget w);

w Specifies the List widget.

XawListShowCurrent returns a pointer to an XawListReturnStruct structure,
containing the currently highlighted item. If the value of the index member is
XAW_LIST_NONE, the string member is undefined, and no item is currently
selected.

Restrictions

Many programmers create a ``scrolled list'' by putting a List widget with many
entries as a child of a Viewport widget. The List continues to create a window
as big as its contents, but that big window is only visible where it intersects
the parent Viewport's window. (I.e., it is ``clipped.'')

While this is a useful technique, there is a serious drawback. X does not
support windows above 32,767 pixels in width or height, but this height limit
will be exceeded by a List's window when the List has many entries (i.e., with
a 12 point font, about 3000 entries would be too many.)

Panner Widget




Application header file <X11/Xaw/Panner.h>

Class header file       <X11/Xaw/PannerP.h>

Class           pannerWidgetClass

Class Name      Panner

Superclass      Simple


A Panner widget is a rectangle, called the ``canvas,'' on which another
rectangle, the ``slider,'' moves in two dimensions. It is often used with a
Porthole widget to move, or ``scroll,'' a third widget in two dimensions, in
which case the slider's size and position gives feedback as to what portion of
the third widget is visible.

The slider may be scrolled around the canvas by pressing, dragging, and
releasing Button1; the default translation also enables scrolling via arrow
keys and some other keys. While scrolling is in progress, the application
receives notification through callback procedures. Notification may be done
either continuously whenever the slider moves or discretely whenever the slider
has been given a new location.

Resources

When creating a Panner widget instance, the following resources are retrieved
from the argument list or from the resource database:

+-----------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value   |
|----------------------+-----------------+----------------+-----+-------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|       allowOff       |    AllowOff     |    Boolean     |     |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|  backgroundStipple   |BackgroundStipple|     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         1         |
|----------------------+-----------------+----------------+-----+-------------------|
|     canvasHeight     |  CanvasHeight   |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|     canvasWidth      |   CanvasWidth   |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|       colormap       |    Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+-----------------+----------------+-----+-------------------|
|        cursor        |     Cursor      |     Cursor     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|      cursorName      |     Cursor      |     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|     defaultScale     |  DefaultScale   |   Dimension    |     |         8         |
|----------------------+-----------------+----------------+-----+-------------------|
|        depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|----------------------+-----------------+----------------+-----+-------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|      foreground      |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|        height        |     Height      |   Dimension    |  A  |    depends on     |
|                      |                 |                |     |    orientation    |
|----------------------+-----------------+----------------+-----+-------------------|
|    internalSpace     |  InternalSpace  |   Dimension    |     |         4         |
|----------------------+-----------------+----------------+-----+-------------------|
|    international     |  International  |    Boolean     |  C  |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|      lineWidth       |    LineWidth    |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|    reportCallback    | ReportCallback  |    Callback    |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        resize        |     Resize      |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      rubberBand      |   RubberBand    |    Boolean     |     |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|        screen        |     Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+-----------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     shadowColor      |   ShadowColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|   shadowThickness    | ShadowThickness |   Dimension    |     |         2         |
|----------------------+-----------------+----------------+-----+-------------------|
|       sliderX        |     SliderX     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|       sliderY        |     SliderY     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|     sliderHeight     |  SliderHeight   |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|     sliderWidth      |   SliderWidth   |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|     translations     |  Translations   |TranslationTable|     |     See below     |
|----------------------+-----------------+----------------+-----+-------------------|
|        width         |      Width      |   Dimension    |  A  |    depends on     |
|                      |                 |                |     |    orientation    |
|----------------------+-----------------+----------------+-----+-------------------|
|          x           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          y           |    Position     |    Position    |     |         0         |
+-----------------------------------------------------------------------------------+

allowOff          Whether to allow the edges of the slider to go off the edges
                  of the canvas.

backgroundStipple The name of a bitmap pattern to be used as the background for
                  the area representing the canvas.

canvasHeight

canvasWidth       The size of the canvas.

defaultScale      The percentage size that the Panner widget should have
                  relative to the size of the canvas.

foreground        A pixel value which indexes the widget's colormap to derive
                  the color used to draw the slider.

                  The width of internal border in pixels between a slider
internalSpace     representing the full size of the canvas and the edge of the
                  Panner widget.

                  The width of the lines in the rubberbanding rectangle when
lineWidth         rubberbanding is in effect instead of continuous scrolling.
                  The default is 0.

                  All functions on this callback list are called when the
reportCallback    notify action is invoked. See the Panner Actions section for
                  details.

resize            Whether or not to resize the panner whenever the canvas size
                  is changed so that the defaultScale is maintained.

                  Whether or not scrolling should be discrete (only moving a
                  rubberbanded rectangle until the scrolling is done) or
rubberBand        continuous (moving the slider itself). This controls whether
                  or not the move action procedure also invokes the notify
                  action procedure.

shadowColor       The color of the shadow underneath the slider.

shadowThickness   The width of the shadow underneath the slider.

sliderX

sliderY           The location of the slider in the coordinates of the canvas.

sliderHeight

sliderWidth       The size of the slider.

Panner Actions

The actions supported by the Panner widget are:

start()           This action begins movement of the slider.

stop()            This action ends movement of the slider.

abort()           This action ends movement of the slider and restores it to
                  the position it held when the start action was invoked.

                  This action moves the outline of the slider (if the
move()            rubberBand resource is True) or the slider itself (by
                  invoking the notify action procedure).

                  This action moves the slider by the specified amounts. The
                  format for the amounts is a signed or unsigned floating-point
page              number (e.g., +1.0 or \-.5) followed by either p indicating
(xamount,yamount) pages (slider sizes), or c indicating canvas sizes. Thus, 
                  page(+0,+.5p) represents vertical movement down one-half the
                  height of the slider and page(0,0) represents moving to the
                  upper left corner of the canvas.

                  This action informs the application of the slider's current
notify()          position by invoking the reportCallback functions registered
                  by the application.

                  This action changes the behavior of the Panner. The what
set(what,value)   argument must currently be the string rubberband and controls
                  the value of the rubberBand resource. The value argument may
                  have one of the values on, off, or toggle.

The default bindings for Panner are:



        <Btn1Down>:     start(\|)
        <Btn1Motion>:   move(\|)
        <Btn1Up>:       notify(\|) stop(\|)
        <Btn2Down>:     abort(\|)
        <Key>KP_Enter:  set(rubberband,toggle)
        <Key>space:     page(+1p,+1p)
        <Key>Delete:    page(\-1p,\-1p)
        <Key>BackSpace: page(\-1p,\-1p)
        <Key>Left:      page(\-.5p,+0)
        <Key>Right:     page(+.5p,+0)
        <Key>Up:        page(+0,\-.5p)
        <Key>Down:      page(+0,+.5p)
        <Key>Home:      page(0,0)

Panner Callbacks

The functions registered on the reportCallback list are invoked by the notify
action as follows:

void ReportProc(Widget panner, XtPointer client_data, XtPointer report);

panner Specifies the Panner widget.

panner Specifies the client data.

panner Specifies a pointer to an XawPannerReport structure containing the
       location and size of the slider and the size of the canvas.

Repeater Widget




Application header file <X11/Xaw/Repeater.h>

Class header file       <X11/Xaw/RepeaterP.h>

Class   repeaterWidgetClass

Class Name      Repeater

Superclass      Command


The Repeater widget is a subclass of the Command widget; see the Command
documentation for details. The difference is that the Repeater can call its
registered callbacks repeatedly, at an increasing rate. The default translation
does so for the duration the user holds down pointer button 1 while the pointer
is on the Repeater.

Resources

When creating a Repeater widget instance, the following resources are retrieved
from the argument list or from the resource database:

+------------------------------------------------------------------------------------+
|         Name         |      Class       |      Type      |Notes|   Default Value   |
|----------------------+------------------+----------------+-----+-------------------|
|     accelerators     |   Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive |    Boolean     |  D  |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|      background      |    Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+------------------+----------------+-----+-------------------|
|   backgroundPixmap   |      Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+------------------+----------------+-----+-------------------|
|        bitmap        |      Bitmap      |     Pixmap     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|     borderPixmap     |      Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+------------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth    |   Dimension    |     |         1         |
|----------------------+------------------+----------------+-----+-------------------|
|       callback       |     Callback     | XtCallbackList |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|       colormap       |     Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+------------------+----------------+-----+-------------------|
|  cornerRoundPercent  |CornerRoundPercent|   Dimension    |     |        25         |
|----------------------+------------------+----------------+-----+-------------------|
|        cursor        |      Cursor      |     Cursor     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|      cursorName      |      Cursor      |     String     |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|        decay         |      Decay       |      Int       |     |         5         |
|----------------------+------------------+----------------+-----+-------------------|
|        depth         |      Depth       |      int       |  C  |  Parent's Depth   |
|----------------------+------------------+----------------+-----+-------------------|
|   destroyCallback    |     Callback     | XtCallbackList |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|       encoding       |     Encoding     |  UnsignedChar  |     |XawTextEncoding8bit|
|----------------------+------------------+----------------+-----+-------------------|
|        flash         |     Boolean      |    Boolean     |     |       False       |
|----------------------+------------------+----------------+-----+-------------------|
|         font         |       Font       |  XFontStruct   |     |   XtDefaultFont   |
|----------------------+------------------+----------------+-----+-------------------|
|       fontSet        |     FontSet      |    XFontSet    |     | XtDefaultFontSet  |
|----------------------+------------------+----------------+-----+-------------------|
|      foreground      |    Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|        height        |      Height      |   Dimension    |  A  |graphic height + 2 |
|                      |                  |                |     | * internalHeight  |
|----------------------+------------------+----------------+-----+-------------------|
|  highlightThickness  |    Thickness     |   Dimension    |  A  |  2 (0 if Shaped)  |
|----------------------+------------------+----------------+-----+-------------------|
|     initialDelay     |      Delay       |      Int       |     |        200        |
|----------------------+------------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive    |     Pixmap     |     |    GreyPixmap     |
|----------------------+------------------+----------------+-----+-------------------|
|    internalHeight    |      Height      |   Dimension    |     |         2         |
|----------------------+------------------+----------------+-----+-------------------|
|    internalWidth     |      Width       |   Dimension    |     |         4         |
|----------------------+------------------+----------------+-----+-------------------|
|    international     |  International   |    Boolean     |  C  |       False       |
|----------------------+------------------+----------------+-----+-------------------|
|       justify        |     Justify      |    Justify     |     |  XtJustifyCenter  |
|                      |                  |                |     |     (center)      |
|----------------------+------------------+----------------+-----+-------------------|
|        label         |      Label       |     String     |     |  name of widget   |
|----------------------+------------------+----------------+-----+-------------------|
|      leftBitmap      |    LeftBitmap    |     Bitmap     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|     minimumDelay     |   MinimumDelay   |      Int       |     |        10         |
|----------------------+------------------+----------------+-----+-------------------|
|     pointerColor     |    Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|pointerColorBackground|    Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+------------------+----------------+-----+-------------------|
|     repeatDelay      |      Delay       |      Int       |     |        50         |
|----------------------+------------------+----------------+-----+-------------------|
|        resize        |      Resize      |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|        screen        |      Screen      |    Pointer     |  R  |  Parent's Screen  |
|----------------------+------------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive     |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|      shapeStyle      |    ShapeStyle    |   ShapeStyle   |     |     Rectangle     |
|----------------------+------------------+----------------+-----+-------------------|
|    startCallback     |  StartCallback   |    Callback    |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|     stopCallback     |   StopCallback   |    Callback    |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|     translations     |   Translations   |TranslationTable|     |     See below     |
|----------------------+------------------+----------------+-----+-------------------|
|        width         |      Width       |   Dimension    |  A  |graphic width + 2 *|
|                      |                  |                |     |   internalWidth   |
|----------------------+------------------+----------------+-----+-------------------|
|          x           |     Position     |    Position    |     |         0         |
|----------------------+------------------+----------------+-----+-------------------|
|          y           |     Position     |    Position    |     |         0         |
+------------------------------------------------------------------------------------+

\" Resource Descriptions

              The number of milliseconds that should be subtracted from each
decay         succeeding interval while the Repeater button is being held down
              until the interval has reached minimumDelay milliseconds.

flash         Whether or not to flash the Repeater button whenever the timer
              goes off.

              The number of milliseconds between the beginning of the Repeater
initialDelay  button being held down and the first invocation of the callback
              function.

minimumDelay  The minimum time between callbacks in milliseconds.

repeatDelay   The number of milliseconds between each callback after the first
              (minus an increasing number of decays).

              The list of functions to invoke by the start action (typically
startCallback when the Repeater button is first pressed). The callback data
              parameter is set to NULL.

              The list of functions to invoke by the stop action (typically
stopCallback  when the Repeater button is released). The callback data
              parameter is set to NULL.

Repeater Actions

The Repeater widget supports the following actions beyond those of the Command
button:

      This invokes the functions on the startCallback and callback lists and
start sets a timer to go off in initialDelay milliseconds. The timer will cause
()    the callback functions to be invoked with increasing frequency until the
      stop action occurs.

stop  This invokes the functions on the stopCallback list and prevents any
()    further timers from occuring until the next start action.

The following are the default translation bindings used by the Repeater widget:



        <EnterWindow>:  highlight(\|)
        <LeaveWindow>:  unhighlight(\|)
        <Btn1Down>:     set(\|) start(\|)
        <Btn1Up>:       stop(\|) unset(\|)

Scrollbar Widget

Application header file     <X11/Xaw/Scrollbar.h>
Class header file           <X11/Xaw/ScrollbarP.h>
Class                       scrollbarWidgetClass
Class Name                  Scrollbar
Superclass                  Simple

A Scrollbar widget is a rectangle, called the ``canvas,'' on which another
rectangle, the ``thumb,'' moves in one dimension, either vertically or
horizontally. A Scrollbar can be used alone, as a value generator, or it can be
used within a composite widget (for example, a Viewport). When a Scrollbar is
used to move, or ``scroll,'' the contents of another widget, the size and the
position of the thumb usually give feedback as to what portion of the other
widget's contents are visible.

Each pointer button invokes a specific action. Pointer buttons 1 and 3 do not
move the thumb automatically. Instead, they return the pixel position of the
cursor on the scroll region. When pointer button 2 is clicked, the thumb moves
to the current pointer position. When pointer button 2 is held down and the
pointer is moved, the thumb follows the pointer.

The pointer cursor in the scroll region changes depending on the current
action. When no pointer button is pressed, the cursor appears as a
double-headed arrow that points in the direction that scrolling can occur. When
pointer button 1 or 3 is pressed, the cursor appears as a single-headed arrow
that points in the logical direction that the thumb will move. When pointer
button 2 is pressed, the cursor appears as an arrow that points to the top or
the left of the thumb.

When the user scrolls, the application receives notification through callback
procedures. For both discrete scrolling actions, the callback returns the
Scrollbar widget, the client_data, and the pixel position of the pointer when
the button was released. For continuous scrolling, the callback routine returns
the scroll bar widget, the client data, and the current relative position of
the thumb. When the thumb is moved using pointer button 2, the callback
procedure is invoked continuously. When either button 1 or 3 is pressed, the
callback procedure is invoked only when the button is released and the client
callback procedure is responsible for moving the thumb.

Resources

When creating a Scrollbar widget instance, the following resources are
retrieved from the argument list or from the resource database:

+------------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value    |
|----------------------+-----------------+----------------+-----+--------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |        NULL        |
|----------------------+-----------------+----------------+-----+--------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |        True        |
|----------------------+-----------------+----------------+-----+--------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground |
|----------------------+-----------------+----------------+-----+--------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap |
|----------------------+-----------------+----------------+-----+--------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground |
|----------------------+-----------------+----------------+-----+--------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap |
|----------------------+-----------------+----------------+-----+--------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         1          |
|----------------------+-----------------+----------------+-----+--------------------|
|       colormap       |    Colormap     |    Colormap    |     | parent's Colormap  |
|----------------------+-----------------+----------------+-----+--------------------|
|        cursor        |     Cursor      |     Cursor     |     |        None        |
|----------------------+-----------------+----------------+-----+--------------------|
|      cursorName      |     Cursor      |     String     |     |        NULL        |
|----------------------+-----------------+----------------+-----+--------------------|
|        depth         |      Depth      |      int       |  C  |   parent's Depth   |
|----------------------+-----------------+----------------+-----+--------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |        NULL        |
|----------------------+-----------------+----------------+-----+--------------------|
|      foreground      |   Foreground    |     Pixel      |     |XtDefaultForeground |
|----------------------+-----------------+----------------+-----+--------------------|
|        height        |     Height      |   Dimension    |  A  |     depends on     |
|                      |                 |                |     |    orientation     |
|----------------------+-----------------+----------------+-----+--------------------|
|  insensitiveBorder   |   Insensitive   |     Pixmap     |     |     GreyPixmap     |
|----------------------+-----------------+----------------+-----+--------------------|
|    international     |  International  |    Boolean     |  C  |       False        |
|----------------------+-----------------+----------------+-----+--------------------|
|       jumpProc       |    Callback     | XtCallbackList |     |        NULL        |
|----------------------+-----------------+----------------+-----+--------------------|
|        length        |     Length      |   Dimension    |     |         1          |
|----------------------+-----------------+----------------+-----+--------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |        True        |
|----------------------+-----------------+----------------+-----+--------------------|
|     minimumThumb     |  MinimumThumb   |   Dimension    |     |         7          |
|----------------------+-----------------+----------------+-----+--------------------|
|     orientation      |   Orientation   |  Orientation   |     |  XtorientVertical  |
|                      |                 |                |     |     (vertical)     |
|----------------------+-----------------+----------------+-----+--------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground |
|----------------------+-----------------+----------------+-----+--------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground |
|----------------------+-----------------+----------------+-----+--------------------|
|        screen        |     Screen      |     Screen     |  R  |  parent's Screen   |
|----------------------+-----------------+----------------+-----+--------------------|
|    scrollDCursor     |     Cursor      |     Cursor     |     |  XC_sb_down_arrow  |
|----------------------+-----------------+----------------+-----+--------------------|
|    scrollHCursor     |     Cursor      |     Cursor     |     |XC_sb_h_double_arrow|
|----------------------+-----------------+----------------+-----+--------------------|
|    scrollLCursor     |     Cursor      |     Cursor     |     |  XC_sb_left_arrow  |
|----------------------+-----------------+----------------+-----+--------------------|
|      scrollProc      |    Callback     | XtCallbackList |     |        NULL        |
|----------------------+-----------------+----------------+-----+--------------------|
|    scrollRCursor     |     Cursor      |     Cursor     |     | XC_sb_right_arrow  |
|----------------------+-----------------+----------------+-----+--------------------|
|    scrollUCursor     |     Cursor      |     Cursor     |     |   XC_sb_up_arrow   |
|----------------------+-----------------+----------------+-----+--------------------|
|    scrollVCursor     |     Cursor      |     Cursor     |     |   XC_sb_v_arrow    |
|----------------------+-----------------+----------------+-----+--------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |        True        |
|----------------------+-----------------+----------------+-----+--------------------|
|        shown         |      Shown      |     Float      |     |        0.0         |
|----------------------+-----------------+----------------+-----+--------------------|
|      thickness       |    Thickness    |   Dimension    |     |         14         |
|----------------------+-----------------+----------------+-----+--------------------|
|        thumb         |      Thumb      |     Bitmap     |     |     GreyPixmap     |
|----------------------+-----------------+----------------+-----+--------------------|
|      thumbProc       |    Callback     | XtCallbackList |     |        NULL        |
|----------------------+-----------------+----------------+-----+--------------------|
|      topOfThumb      |   TopOfThumb    |     Float      |     |        0.0         |
|----------------------+-----------------+----------------+-----+--------------------|
|     translations     |  Translations   |TranslationTable|     |     See below      |
|----------------------+-----------------+----------------+-----+--------------------|
|        width         |      Width      |   Dimension    |  A  |     depends on     |
|                      |                 |                |     |    orientation     |
|----------------------+-----------------+----------------+-----+--------------------|
|          x           |    Position     |    Position    |     |         0          |
|----------------------+-----------------+----------------+-----+--------------------|
|          y           |    Position     |    Position    |     |         0          |
+------------------------------------------------------------------------------------+

foreground    A pixel value which indexes the widget's colormap to derive the
              color used to draw the thumb.

              All functions on this callback list are called when the
jumpProc      NotifyThumb action is invoked. See the Scrollbar Actions section
              for details.

length        The height of a vertical scrollbar or the width of a horizontal
              scrollbar.

minimumThumb  The smallest size, in pixels, to which the thumb can shrink.

              The orientation is the direction that the thumb will be allowed
orientation   to move. This value can be either XtorientVertical or
              XtorientHorizontal.

scrollDCursor This cursor is used when scrolling backward in a vertical
              scrollbar.

scrollHCursor This cursor is used when a horizontal scrollbar is inactive.

scrollLCursor This cursor is used when scrolling forward in a horizontal
              scrollbar.

              All functions on this callback list may be called when the
scrollProc    NotifyScroll action is invoked. See the \fBScrollbar Actions\fP
              section for details.

scrollRCursor This cursor is used when scrolling backward in a horizontal
              scrollbar, or when thumbing a vertical scrollbar.

scrollUCursor This cursor is used when scrolling forward in a vertical
              scrollbar, or when thumbing a horizontal scrollbar.

scrollVCursor This cursor is used when a vertical scrollbar is inactive.

shown         This is the size of the thumb, expressed as a percentage (0.0 -
              1.0) of the length of the scrollbar.

thickness     The width of a vertical scrollbar or the height of a horizontal
              scrollbar.

              This pixmap is used to tile (or stipple) the thumb of the
              scrollbar. If no tiling is desired, then set this resource to
thumb         None. This resource will accept either a bitmap or a pixmap that
              is the same depth as the window. The resource converter for this
              resource constructs bitmaps from the contents of files. (See
              Converting Bitmaps for details.)

              The location of the top of the thumb, as a percentage (0.0 - 1.0)
              of the length of the scrollbar. This resource was called top in
topOfThumb    previous versions of the Athena widget set. The name collided
              with the a Form widget constraint resource, and had to be
              changed.

Scrollbar Actions

The actions supported by the Scrollbar widget are:

StartScroll( The possible values are Forward, Backward, or Continuous. This
value)       must be the first action to begin a new movement.

             The possible values are Proportional or FullLength. If the
             argument to StartScroll was Forward or Backward, NotifyScroll
NotifyScroll executes the scrollProc callbacks and passes either; the position
(value)      of the pointer, if value is Proportional, or the full length of
             the scroll bar, if value is FullLength. If the argument to
             StartScroll was Continuous, NotifyScroll returns without executing
             any callbacks.

EndScroll(\  This must be the last action after a movement is complete.
^)

MoveThumb(\  Repositions the Scrollbar's thumb to the current pointer location.
^)

NotifyThumb  Calls the callbacks and passes the relative position of the
(\^)\        pointer as a percentage of the scroll bar length.

The default bindings for Scrollbar are:

     <Btn1Down>:     StartScroll(Forward)
     <Btn2Down>:     StartScroll(Continuous) MoveThumb(\|) NotifyThumb(\|)
     <Btn3Down>:     StartScroll(Backward)
     <Btn2Motion>:     MoveThumb(\|) NotifyThumb(\|)
     <BtnUp>:     NotifyScroll(Proportional) EndScroll(\|)

Examples of additional bindings a user might wish to specify in a resource file
are:

*Scrollbar.Translations: \\
     ~Meta<Key>space:     StartScroll(Forward) NotifyScroll(FullLength) \\n\\
      Meta<Key>space:     StartScroll(Backward) NotifyScroll(FullLength) \\n\\
          EndScroll(\|)

Scrollbar Callbacks

There are two callback lists provided by the Scrollbar widget. The procedural
interface for these functions is described here.

The calling interface to the scrollProc callback procedure is:

void ScrollProc(Widget scrollbar, XtPointer client_data, XtPointer position);

scrollbar   Specifies the Scrollbar widget.

client_data Specifies the client data.

position    Specifies a pixel position in integer form.

The scrollProc callback is used for incremental scrolling and is called by the
NotifyScroll action. The position argument is a signed quantity and should be
cast to an int when used. Using the default button bindings, button 1 returns a
positive value, and button 3 returns a negative value. In both cases, the
magnitude of the value is the distance of the pointer in pixels from the top
(or left) of the Scrollbar. The value will never be greater than the length of
the Scrollbar.

The calling interface to the jumpProc callback procedure is:

void JumpProc(Widget scrollbar, XtPointer client_data, XtPointer percent_ptr);

scrollbar   Specifies the ID of the scroll bar widget.

client_data Specifies the client data.

percent_ptr Specifies the floating point position of the thumb (0.0 \- 1.0).

The jumpProc callback is used to implement smooth scrolling and is called by
the NotifyThumb action. Percent_ptr must be cast to a pointer to float before
use; i.e.

     float percent = *(float*)percent_ptr;

With the default button bindings, button 2 moves the thumb interactively, and
the jumpProc is called on each new position of the pointer, while the pointer
button remains down. The value specified by percent_ptr is the current location
of the thumb (from the top or left of the Scrollbar) expressed as a percentage
of the length of the Scrollbar.

Convenience Routines

To set the position and length of a Scrollbar thumb, use

void XawScrollbarSetThumb(Widget w, float top, float shown);

w     Specifies the Scrollbar widget.

top   Specifies the position of the top of the thumb as a fraction of the
      length of the Scrollbar.

shown Specifies the length of the thumb as a fraction of the total length of
      the Scrollbar.

XawScrollbarThumb moves the visible thumb to a new position (0.0 \- 1.0) and
length (0.0 \- 1.0). Either the top or shown arguments can be specified as \
-1.0, in which case the current value is left unchanged. Values greater than
1.0 are truncated to 1.0.

If called from jumpProc, XawScrollbarSetThumb has no effect.

Setting Float Resources

The shown and topOfThumb resources are of type float. These resources can be
difficult to get into an argument list. The reason is that C performs an
automatic cast of the float value to an integer value, usually truncating the
important information. The following code fragment is one portable method of
getting a float into an argument list.

     top = 0.5;
     if (sizeof(float) > sizeof(XtArgVal)) {
     /*
     \ * If a float is larger than an XtArgVal then pass this
     \ * resource value by reference.
     \ */
          XtSetArg(args[0], XtNshown, &top);
     }
     else {
     /*
     \ * Convince C not to perform an automatic conversion, which
     \ * would truncate 0.5 to 0.
     \ */
          XtArgVal * l_top = (XtArgVal *) &top;
          XtSetArg(args[0], XtNshown, *l_top);
     }

Simple Widget




Application Header file <Xaw/Simple.h>

Class Header file       <Xaw/SimpleP.h>

Class           simpleWidgetClass

Class Name      Simple

Superclass      Core


The Simple widget is not very useful by itself, as it has no semantics of its
own. It main purpose is to be used as a common superclass for the other simple
Athena widgets. This widget adds six resources to the resource list provided by
the Core widget and its superclasses.

Resources

When creating a Simple widget instance, the following resources are retrieved
from the argument list or from the resource database:

+-----------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value   |
|----------------------+-----------------+----------------+-----+-------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         1         |
|----------------------+-----------------+----------------+-----+-------------------|
|       colormap       |    Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+-----------------+----------------+-----+-------------------|
|        cursor        |     Cursor      |     Cursor     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|      cursorName      |     Cursor      |     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|----------------------+-----------------+----------------+-----+-------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        height        |     Height      |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |     Pixmap     |     |    GreyPixmap     |
|----------------------+-----------------+----------------+-----+-------------------|
|    international     |  International  |    Boolean     |  C  |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|        screen        |     Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+-----------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     translations     |  Translations   |TranslationTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        width         |      Width      |   Dimension    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          x           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          y           |    Position     |    Position    |     |         0         |
+-----------------------------------------------------------------------------------+

StripChart Widget




Application Header file <Xaw/StripChart.h>

Class Header file       <Xaw/StripCharP.h>

Class           stripChartWidgetClass

Class Name      StripChart

Superclass      Simple


The StripChart widget is used to provide a roughly real time graphical chart of
a single value. For example, it is used by the common client program xload to
provide a graph of processor load. The StripChart reads data from an
application, and updates the chart at the update interval specified.

Resources

When creating a StripChart widget instance, the following resources are
retrieved from the argument list or from the resource database:

+-----------------------------------------------------------------------------------+
|         Name         |      Class      |      Type      |Notes|   Default Value   |
|----------------------+-----------------+----------------+-----+-------------------|
|     accelerators     |  Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|      background      |   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+-----------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |   Dimension    |     |         1         |
|----------------------+-----------------+----------------+-----+-------------------|
|       colormap       |    Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+-----------------+----------------+-----+-------------------|
|        cursor        |     Cursor      |     Cursor     |     |       None        |
|----------------------+-----------------+----------------+-----+-------------------|
|      cursorName      |     Cursor      |     String     |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|----------------------+-----------------+----------------+-----+-------------------|
|   destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|      foreground      |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|       getValue       |    Callback     | XtCallbackList |     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        height        |     Height      |   Dimension    |     |        120        |
|----------------------+-----------------+----------------+-----+-------------------|
|      highlight       |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |     Pixmap     |     |    GreyPixmap     |
|----------------------+-----------------+----------------+-----+-------------------|
|    international     |  International  |    Boolean     |  C  |       False       |
|----------------------+-----------------+----------------+-----+-------------------|
|      jumpScroll      |   JumpScroll    |      int       |  A  | half the width of |
|                      |                 |                |     |    the widget     |
|----------------------+-----------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|       minScale       |      Scale      |      int       |     |         1         |
|----------------------+-----------------+----------------+-----+-------------------|
|     pointerColor     |   Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+-----------------+----------------+-----+-------------------|
|pointerColorBackground|   Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+-----------------+----------------+-----+-------------------|
|        screen        |     Screen      |    Pointer     |  R  |  Parent's Screen  |
|----------------------+-----------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive    |    Boolean     |     |       True        |
|----------------------+-----------------+----------------+-----+-------------------|
|     translations     |  Translations   |TranslationTable|     |       NULL        |
|----------------------+-----------------+----------------+-----+-------------------|
|        update        |    Interval     |      int       |     |        10         |
|----------------------+-----------------+----------------+-----+-------------------|
|        width         |      Width      |   Dimension    |     |        120        |
|----------------------+-----------------+----------------+-----+-------------------|
|          x           |    Position     |    Position    |     |         0         |
|----------------------+-----------------+----------------+-----+-------------------|
|          y           |    Position     |    Position    |     |         0         |
+-----------------------------------------------------------------------------------+

foreground A pixel value which indexes the widget's colormap to derive the
           color that will be used to draw the graph.

           A list of callback functions to call every update seconds. This list
           should contain one function, which returns the value to be graphed
getValue   by the StripChart widget. The following section describes the
           procedural interface. Behavior when this list has more than one
           function is undefined.

highlight  A pixel value which indexes the widget's colormap to derive the
           color that will be used to draw the scale lines on the graph.

           When the graph reaches the right edge of the window it must be
jumpScroll scrolled to the left. This resource specifies the number of pixels
           it will jump. Smooth scrolling can be achieved by setting this
           resource to 1.

minScale   The minimum scale for the graph. The number of divisions on the
           graph will always be greater than or equal to this value.

           The number of seconds between graph updates. Each update is
           represented on the graph as a 1 pixel wide line. Every update
update     seconds the getValue procedure will be used to get a new graph
           point, and this point will be added to the right end of the
           StripChart.

Getting the StripChart Value

The StripChart widget will call the application routine passed to it as the
getValue callback function every update seconds to obtain another point for the
StripChart graph.

The calling interface for the getValue callback is:

void(*getValueProc)(Widget w, XtPointer client_data, XtPointer value);

w           Specifies the StripChart widget.

client_data Specifies the client data.

            Returns a pointer to a double. The application should set the
value       address pointed to by this argument to a double containing the
            value to be graphed on the StripChart.

This function is used by the StripChart to call an application routine. The
routine will pass the value to be graphed back to the the StripChart in the
value field of this routine.

Toggle Widget

Application Header file     <Xaw/Toggle.h>
Class Header file     <Xaw/ToggleP.h>
Class          toggleWidgetClass
Class Name     Toggle
Superclass      Command

The Toggle widget is an area, often rectangular, that displays a graphic. The
graphic may be a text string containing multiple lines of characters in an 8
bit or 16 bit character set (to be displayed with a font), or in a multi-byte
encoding (for use with a fontset). The graphic may also be a bitmap or pixmap.

This widget maintains a Boolean state (e.g. True/False or On/Off) and changes
state whenever it is selected. When the pointer is on the Toggle widget, the
Toggle widget may become highlighted by drawing a rectangle around its
perimeter. This highlighting indicates that the Toggle widget is ready for
selection. When pointer button 1 is pressed and released, the Toggle widget
indicates that it has changed state by reversing its foreground and background
colors, and its notify action is invoked, calling all functions on its callback
list. If the pointer is moved off of the widget before the pointer button is
released, the Toggle widget reverts to its previous foreground and background
colors, and releasing the pointer button has no effect. This behavior allows
the user to cancel the operation.

Toggle widgets may also be part of a ``radio group.'' A radio group is a list
of at least two Toggle widgets in which no more than one Toggle may be set at
any time. A radio group is identified by the widget ID of any one of its
members. The convenience routine XawToggleGetCurrent will return information
about the Toggle widget in the radio group.

Toggle widget state is preserved across changes in sensitivity.

Resources

When creating a Toggle widget instance, the following resources are retrieved
from the argument list or from the resource database:

+------------------------------------------------------------------------------------+
|         Name         |      Class       |      Type      |Notes|   Default Value   |
|----------------------+------------------+----------------+-----+-------------------|
|     accelerators     |   Accelerators   |AcceleratorTable|     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive |    Boolean     |  D  |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|      background      |    Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+------------------+----------------+-----+-------------------|
|   backgroundPixmap   |      Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+------------------+----------------+-----+-------------------|
|        bitmap        |      Bitmap      |     Pixmap     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|     borderColor      |   BorderColor    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|     borderPixmap     |      Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|----------------------+------------------+----------------+-----+-------------------|
|     borderWidth      |   BorderWidth    |   Dimension    |     |         1         |
|----------------------+------------------+----------------+-----+-------------------|
|       callback       |     Callback     | XtCallbackList |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|       colormap       |     Colormap     |    Colormap    |     | Parent's Colormap |
|----------------------+------------------+----------------+-----+-------------------|
|  cornerRoundPercent  |CornerRoundPercent|   Dimension    |     |        25         |
|----------------------+------------------+----------------+-----+-------------------|
|        cursor        |      Cursor      |     Cursor     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|      cursorName      |      Cursor      |     String     |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|        depth         |      Depth       |      int       |  C  |  Parent's Depth   |
|----------------------+------------------+----------------+-----+-------------------|
|   destroyCallback    |     Callback     | XtCallbackList |     |       NULL        |
|----------------------+------------------+----------------+-----+-------------------|
|       encoding       |     Encoding     |  UnsignedChar  |     |XawTextEncoding8bit|
|----------------------+------------------+----------------+-----+-------------------|
|         font         |       Font       |  XFontStruct   |     |   XtDefaultFont   |
|----------------------+------------------+----------------+-----+-------------------|
|       fontSet        |     FontSet      |    XFontSet    |     | XtDefaultFontSet  |
|----------------------+------------------+----------------+-----+-------------------|
|      foreground      |    Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|        height        |      Height      |   Dimension    |  A  |graphic height + 2 |
|                      |                  |                |     | * internalHeight  |
|----------------------+------------------+----------------+-----+-------------------|
|  highlightThickness  |    Thickness     |   Dimension    |  A  |  2 (0 if Shaped)  |
|----------------------+------------------+----------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive    |     Pixmap     |     |    GreyPixmap     |
|----------------------+------------------+----------------+-----+-------------------|
|    internalHeight    |      Height      |   Dimension    |     |         2         |
|----------------------+------------------+----------------+-----+-------------------|
|    internalWidth     |      Width       |   Dimension    |     |         4         |
|----------------------+------------------+----------------+-----+-------------------|
|    international     |  International   |    Boolean     |  C  |       False       |
|----------------------+------------------+----------------+-----+-------------------|
|       justify        |     Justify      |    Justify     |     |  XtJustifyCenter  |
|                      |                  |                |     |     (center)      |
|----------------------+------------------+----------------+-----+-------------------|
|        label         |      Label       |     String     |     |  name of widget   |
|----------------------+------------------+----------------+-----+-------------------|
|      leftBitmap      |    LeftBitmap    |     Bitmap     |     |       None        |
|----------------------+------------------+----------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|     pointerColor     |    Foreground    |     Pixel      |     |XtDefaultForeground|
|----------------------+------------------+----------------+-----+-------------------|
|pointerColorBackground|    Background    |     Pixel      |     |XtDefaultBackground|
|----------------------+------------------+----------------+-----+-------------------|
|      radioData       |    RadioData     |    Pointer     |     |  Name of widget   |
|----------------------+------------------+----------------+-----+-------------------|
|      radioGroup      |      Widget      |     Widget     |     |  No radio group   |
|----------------------+------------------+----------------+-----+-------------------|
|        resize        |      Resize      |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|        screen        |      Screen      |     Screen     |  R  |  Parent's Screen  |
|----------------------+------------------+----------------+-----+-------------------|
|      sensitive       |    Sensitive     |    Boolean     |     |       True        |
|----------------------+------------------+----------------+-----+-------------------|
|      shapeStype      |    ShapeStyle    |   ShapeStyle   |     |     Rectangle     |
|----------------------+------------------+----------------+-----+-------------------|
|        state         |      State       |    Boolean     |     |        Off        |
|----------------------+------------------+----------------+-----+-------------------|
|     translations     |   Translations   |TranslationTable|     |     See below     |
|----------------------+------------------+----------------+-----+-------------------|
|        width         |      Width       |   Dimension    |  A  |graphic width + 2 *|
|                      |                  |                |     |   internalWidth   |
|----------------------+------------------+----------------+-----+-------------------|
|          x           |     Position     |    Position    |     |         0         |
|----------------------+------------------+----------------+-----+-------------------|
|          y           |     Position     |    Position    |     |         0         |
+------------------------------------------------------------------------------------+

           Specifies the data that will be returned by XawToggleGetCurrent when
           this is the currently set widget in the radio group. This value is
radioData  also used to identify the Toggle that will be set by a call to
           XawToggleSetCurrent. The value NULL will be returned by
           XawToggleGetCurrent if no widget in a radio group is currently set.
           Programmers must not specify NULL (or Zero) as radioData.

           Specifies another Toggle widget that is in the radio group to which
           this Toggle widget should be added. A radio group is a group of at
           least two Toggle widgets, only one of which may be set at a time. If
           this value is NULL (the default) then the Toggle will not be part of
           any radio group and can change state without affecting any other
radioGroup Toggle widgets. If the widget specified in this resource is not
           already in a radio group then a new radio group will be created
           containing these two Toggle widgets. No Toggle widget can be in
           multiple radio groups. The behavior of a radio group of one toggle
           is undefined. A converter is registered which will convert widget
           names to widgets without caching.

state      Specifies whether the Toggle widget is set (True) or unset (False).

Toggle Actions

The Toggle widget supports the following actions:

  * Switching the Toggle widget between the foreground and background colors
    with set and unset and toggle

  * Processing application callbacks with notify

  * Switching the internal border between highlighted and unhighlighted states
    with highlight and unhighlight

The following are the default translation bindings used by the Toggle widget:

     <EnterWindow>:     highlight(Always)
     <LeaveWindow>:     unhighlight()
     <Btn1Down>,<Btn1Up>:     toggle() notify()

Toggle Actions

The full list of actions supported by Toggle is:

            Displays the internal highlight border in the color (foreground or
highlight(  background ) that contrasts with the interior color of the Toggle
condition)  widget. The conditions WhenUnset and Always are understood by this
            action procedure. If no argument is passed then WhenUnset is
            assumed.

unhighlight Displays the internal highlight border in the color (foreground or
()          background ) that matches the interior color of the Toggle widget.

            Enters the set state, in which notify is possible. This action
set()       causes the Toggle widget to display its interior in the foreground
            color. The label or bitmap is displayed in the background color.

            Cancels the set state and displays the interior of the Toggle
unset()     widget in the background color. The label or bitmap is displayed in
            the foreground color.

            Changes the current state of the Toggle widget, causing to be set
            if it was previously unset, and unset if it was previously set. If
            the widget is to be set, and is in a radio group then this
toggle()    procedure may unset another Toggle widget causing all routines on
            its callback list to be invoked. The callback routines for the
            Toggle that is to be unset will be called before the one that is to
            be set.

            Cancels any set or highlight and displays the interior of the
reset()     Toggle widget in the background color, with the label displayed in
            the foreground color.

            When the Toggle widget is in the set state this action calls all
notify()    functions in the callback list named by the callback resource. The
            value of the call_data argument in these callback functions is
            undefined.

When a bitmap of depth greater that one (1) is specified the set(), unset(),
and reset() actions have no effect, since there are no foreground and
background colors used in a multi-plane pixmap.

Radio Groups

There are typically two types of radio groups desired by applications. The
default translations for the Toggle widget implement a "zero or one of many"
radio group. This means that there may be no more than one Toggle widget
active, but there need not be any Toggle widgets active.

The other type of radio group is "one of many" and has the more strict policy
that there will always be exactly one radio button active. Toggle widgets can
be used to provide this interface with a slight modification to the translation
table of each Toggle in the group.

     <EnterWindow>:     highlight(Always)
     <LeaveWindow>:     unhighlight()
     <Btn1Down>,<Btn1Up>:     set() notify()

This translation table will not allow any Toggle to be unset except as a result
of another Toggle becoming set. It is the application programmer's
responsibility to choose an initial state for the radio group by setting the
state resource of one of its member widgets to True.

Convenience Routines

The following functions allow easy access to the Toggle widget's radio group
functionality.

Changing the Toggle's Radio Group.

To enable an application to change the Toggle's radio group, add the Toggle to
a radio group, or remove the Toggle from a radio group, use
XawToggleChangeRadioGroup.

void XawToggleChangeRadioGroup(Widgetw, radio_group);

w           Specifies the Toggle widget.

            Specifies any Toggle in the new radio group. If NULL then the
radio_group Toggle will be removed from any radio group of which it is a
            member.

If a Toggle is already set in the new radio group, and the Toggle to be added
is also set then the previously set Toggle in the radio group is unset and its
callback procedures are invoked. Finding the Currently selected Toggle in a
radio group of Toggles

To find the currently selected Toggle in a radio group of Toggle widgets use
XawToggleGetCurrent.

XtPointer XawToggleGetCurrent(XtPointer XawToggleGetCurrent(radio_group),
Widget radio_group);

radio_group Specifies any Toggle widget in the radio group.

The value returned by this function is the radioData of the Toggle in this
radio group that is currently set. The default value for radioData is the name
of that Toggle widget. If no Toggle is set in the radio group specified then
NULL is returned. Changing the Toggle that is set in a radio group.

To change the Toggle that is currently set in a radio group use
XawToggleSetCurrent.

void XawToggleSetCurrent(voidXawToggleSetCurrent(radio_group, radio_data),
Widget radio_group, XtPointer radio_data);

radio_group Specifies any Toggle widget in the radio group.

radio_data  Specifies the radioData identifying the Toggle that should be set
            in the radio group specified by the radio_group argument.

XawToggleSetCurrent locates the Toggle widget to be set by matching radio_data
against the radioData for each Toggle in the radio group. If none match,
XawToggleSetCurrent returns without making any changes. If more than one Toggle
matches, XawToggleSetCurrent will choose a Toggle to set arbitrarily. If this
causes any Toggle widgets to change state, all routines in their callback lists
will be invoked. The callback routines for a Toggle that is to be unset will be
called before the one that is to be set. Unsetting all Toggles in a radio
group.

To unset all Toggle widgets in a radio group use XawToggleUnsetCurrent.

void XawToggleUnsetCurrent(void XawToggleUnsetCurrent(radio_group), Widget
radio_group);

radio_group Specifies any Toggle widget in the radio group.

If this causes a Toggle widget to change state, all routines on its callback
list will be invoked.

Chapter 4. Menus

Table of Contents

Using the Menus
Sme Object

    Resources
    Subclassing the Sme Object

SmeBSB Object

    Resources

SmeLine Object

    Resources

The Athena widget set provides support for single paned non-hierarchical popup
and pulldown menus. Since menus are such a common user interface tool, support
for them must be provided in even the most basic widget sets. In menuing as in
other areas, the Athena Widget Set provides only basic functionality.

Menus in the Athena widget set are implemented as a menu container (the
SimpleMenu widget) and a collection of objects that comprise the menu entries.
The SimpleMenu widget is itself a direct subclass of the OverrideShell widget
class, so no other shell is necessary when creating a menu. The managed
children of a SimpleMenu must be subclasses of the Sme (Simple Menu Entry)
object.

The Athena widget set provides three classes of Sme objects that may be used to
build menus.

        The base class of all menu entries. It may be used as a menu entry
Sme     itself to provide blank space in a menu. "Sme" means "Simple Menu
        Entry."

        This menu entry provides a selectable entry containing a text string. A
SmeBSB  bitmap may also be placed in the left and right margins. "BSB" means
        "Bitmap String Bitmap."

SmeLine This menu entry provides an unselectable entry containing a separator
        line.

The SimpleMenu widget informs the window manager that it should ignore its
window by setting the Override Redirect flag. This is the correct behavior for
the press-drag-release style of menu operation. If click-move-click or
"pinable" menus are desired it is the responsibility of the application
programmer, using the SimpleMenu resources, to inform the window manager of the
menu.

To allow easy creation of pulldown menus, a MenuButton widget is also provided
as part of the Athena widget set.

Using the Menus

The default configuration for the menus is press-drag-release. The menus will
typically be activated by clicking a pointer button while the pointer is over a
MenuButton, causing the menu to appear in a fixed location relative to that
button; this is a pulldown menu. Menus may also be activated when a specific
pointer and/or key sequence is used anywhere in the application; this is a
popup menu (e.g. clicking Ctrl-<pointer button 1> in the common application
xterm). In this case the menu should be positioned under the cursor. Typically
menus will be placed so the pointer cursor is on the first menu entry, or the
last entry selected by the user.

The menu remains on the screen as long as the pointer button is held down.
Moving the pointer will highlight different menu items. If the pointer leaves
the menu, or moves over an entry that cannot be selected then no menu entry
will highlighted. When the desired menu entry has been highlighted, releasing
the pointer button removes the menu, and causes any mechanism associated with
this entry to be invoked.

Sme Object



Application Header file <X11/Xaw/Sme.h>

Class Header file       <X11/Xaw/SmeP.h>

Class           smeObjectClass

Class Name      Sme

Superclass      RectObj

The Sme object is the base class for all menu entries. While this object is
mainly intended to be subclassed, it may be used in a menu to add blank space
between menu entries.

Resources

The resources associated with the SmeLine object are defined in this section,
and affect only the single menu entry specified by this object. There are no
new resources added for this class, as it picks up all its resources from the
RectObj class.

+----------------------------------------------------------------------+
|      Name       |      Class      |     Type     |Notes|Default Value|
|-----------------+-----------------+--------------+-----+-------------|
|ancestorSensitive|AncestorSensitive|   Boolean    |     |    True     |
|-----------------+-----------------+--------------+-----+-------------|
|    callback     |    Callback     |XtCallbackList|     |    NULL     |
|-----------------+-----------------+--------------+-----+-------------|
| destroyCallback |    Callback     |XtCallbackList|     |    NULL     |
|-----------------+-----------------+--------------+-----+-------------|
|     height      |     Height      |  Dimension   |     |      0      |
|-----------------+-----------------+--------------+-----+-------------|
|  international  |  International  |   Boolean    |  C  |    False    |
|-----------------+-----------------+--------------+-----+-------------|
|    sensitive    |    Sensitive    |   Boolean    |     |    True     |
|-----------------+-----------------+--------------+-----+-------------|
|      width      |      Width      |  Dimension   |     |      1      |
+----------------------------------------------------------------------+

Keep in mind that the SimpleMenu widget will force all menu items to be the
width of the widest entry.

Subclassing the Sme Object

To Create a new Sme object class you will need to define three class methods.
These methods allow the SimpleMenu to highlight and unhighlight the menu entry
as the pointer cursor moves over it, as well as notify the entry when the user
has selected it. All of these methods may be inherited from the Sme object,
although the default semantics are not very interesting.

Highlight(\|)   Called to put the menu entry into the highlighted state.

Unhighlight(\|) Called to return the widget to its normal (unhighlighted)
                state.

Notify(\|)      Called when the user selects this menu entry.

Other then these methods, creating a new object is straight forward. Here is
some information that may help you avoid some common mistakes.

 1. Objects can be zero pixels high.

 2. Objects draw on their parent's window, therefore the Drawing dimensions are
    different from those of widgets. For instance, y locations vary from y to y
    + height, not 0 to height.

 3. XtSetValues calls may come from the application while the Sme is
    highlighted, and if the SetValues method returns True, will result in an
    expose event. The SimpleMenu may later call the menu entry's unhighlight
    procedure. However, due to the asynchronous nature of X, the expose event
    generated by XtSetValues will come after this unhighlight.

 4. Remember that your subclass of the Sme does not own the window. Share the
    space with other menu entries, and refrain from drawing outside the
    subclass's own section of the menu.

SmeBSB Object




Application Header file <X11/Xaw/SmeBSB.h>

Class Header file       <X11/Xaw/SmeBSBP.h>

Class           smeBSBObjectClass

Class Name      SmeBSB

Superclass      Sme


The SmeBSB object is used to create a menu entry that contains a string, and
optional bitmaps in its left and right margins. Since each menu entry is an
independent object, the application is able to change the font, color, height,
and other attributes of the menu entries, on an entry by entry basis. The
format of the string may either be the encoding of the 8 bit font utilized, or
in a multi-byte encoding for use with a fontSet.

Resources

The resources associated with the SmeBSB object are defined in this section,
and affect only the single menu entry specified by this object.

+-----------------------------------------------------------------------------+
|      Name       |      Class      |     Type     |Notes|   Default Value    |
|-----------------+-----------------+--------------+-----+--------------------|
|ancestorSensitive|AncestorSensitive|   Boolean    |  D  |        True        |
|-----------------+-----------------+--------------+-----+--------------------|
|    callback     |    Callback     |   Callback   |     |        NULL        |
|-----------------+-----------------+--------------+-----+--------------------|
| destroyCallback |    Callback     |XtCallbackList|     |        NULL        |
|-----------------+-----------------+--------------+-----+--------------------|
|      font       |      Font       |  FontStruct  |     |   XtDefaultFont    |
|-----------------+-----------------+--------------+-----+--------------------|
|     fontSet     |     FontSet     |   XFontSet   |     |  XtDefaultFontSet  |
|-----------------+-----------------+--------------+-----+--------------------|
|   foreground    |   Foreground    |    Pixel     |     |XtDefaultForeground |
|-----------------+-----------------+--------------+-----+--------------------|
|     height      |     Height      |  Dimension   |  A  |   Font height +    |
|                 |                 |              |     |     vertSpace      |
|-----------------+-----------------+--------------+-----+--------------------|
|  international  |  International  |   Boolean    |  C  |       False        |
|-----------------+-----------------+--------------+-----+--------------------|
|     justify     |     Justify     |   Justify    |     |   XtjustifyLeft    |
|-----------------+-----------------+--------------+-----+--------------------|
|      label      |      Label      |    String    |     |        NULL        |
|-----------------+-----------------+--------------+-----+--------------------|
|   leftBitmap    |   LeftBitmap    |    Pixmap    |     |XtUnspecifiedPixmap |
|-----------------+-----------------+--------------+-----+--------------------|
|   leftMargin    |   leftMargin    |  Dimension   |     |         4          |
|-----------------+-----------------+--------------+-----+--------------------|
|   rightBitmap   |   RightBitmap   |    Pixmap    |     |XtUnspecifiedPixmap |
|-----------------+-----------------+--------------+-----+--------------------|
|   rightMargin   |   rightMargin   |  Dimension   |     |         4          |
|-----------------+-----------------+--------------+-----+--------------------|
|    sensitive    |    Sensitive    |   Boolean    |     |        True        |
|-----------------+-----------------+--------------+-----+--------------------|
|    vertSpace    |    VertSpace    |     int      |     |         25         |
|-----------------+-----------------+--------------+-----+--------------------|
|      width      |      Width      |  Dimension   |  A  |TextWidth + margins |
+-----------------------------------------------------------------------------+

callback    All callback functions on this list are called when the SimpleMenu 
            notifies this entry that the user has selected it.

font        The text font to use when displaying the label, when the
            international resource is false.

fontSet     The text font set to use when displaying the label, when the
            international resource is true.

            A pixel value which indexes the SimpleMenu's colormap to derive the
            foreground color of the menu entry's window. This color is also
foreground  used to render all 1's in the left and right bitmaps. Keep in mind
            that the SimpleMenu widget will force the width of all menu entries
            to be the width of the longest entry.

            How the label is to be rendered between the left and right margins
            when the space is wider than the actual text. This resource may be
justify     specified with the values XtJustifyLeft, XtJustifyCenter, or
            XtJustifyRight. When specifying the justification from a resource
            file the values left, center, or right may be used.

            This is a the string that will be displayed in the menu entry. The
label       exact location of this string within the bounds of the menu entry
            is controlled by the leftMargin, rightMargin, vertSpace, and
            justify resources.

leftBitmap

            This is a name of a bitmap to display in the left or right margin
            of the menu entry. All 1's in the bitmap will be rendered in the
            foreground color, and all 0's will be drawn in the background color
rightBitmap of the SimpleMenu widget. It is the programmers' responsibility to
            make sure that the menu entry is tall enough, and the appropriate
            margin wide enough to accept the bitmap. If care is not taken the
            bitmap may extend into another menu entry, or into this entry's
            label.

leftMargin

rightMargin This is the amount of space (in pixels) that will be left between
            the edge of the menu entry and the label string.

            This is the amount of vertical padding, expressed as a percentage
            of the height of the font, that is to be placed around the label of
vertSpace   a menu entry.. The label and bitmaps are always centered vertically
            within the menu. The default value for this resource (25) causes
            the default height to be 125% of the height of the font.

SmeLine Object



Application Header file <X11/Xaw/SmeLine.h>

Class Header file       <X11/Xaw/SmeLineP.h>

Class           smeLineObjectClass

Class Name      SmeLine

Superclass      Sme

The SmeLine object is used to add a horizontal line or menu separator to a
menu. Since each SmeLine is an independent object, the application is able to
change the color, height, and other attributes of the SmeLine objects on an
entry by entry basis. This object is not selectable, and will not highlight
when the pointer cursor is over it.

Resources

The resources associated with the SmeLine object are defined in this section,
and affect only the single menu entry specified by this object.

+----------------------------------------------------------------------+
|     Name      |    Class    |     Type     |Notes|   Default Value   |
|---------------+-------------+--------------+-----+-------------------|
|destroyCallback|  Callback   |XtCallbackList|     |       NULL        |
|---------------+-------------+--------------+-----+-------------------|
|  foreground   | Foreground  |    Pixel     |     |XtDefaultForeground|
|---------------+-------------+--------------+-----+-------------------|
|    height     |   Height    |  Dimension   |     |     lineWidth     |
|---------------+-------------+--------------+-----+-------------------|
| international |International|   Boolean    |  C  |       False       |
|---------------+-------------+--------------+-----+-------------------|
|   lineWidth   |  LineWidth  |  Dimension   |     |         1         |
|---------------+-------------+--------------+-----+-------------------|
|    stipple    |   Stipple   |    Pixmap    |     |XtUnspecifiedPixmap|
|---------------+-------------+--------------+-----+-------------------|
|     width     |    Width    |  Dimension   |     |         1         |
+----------------------------------------------------------------------+

           A pixel value which indexes the SimpleMenu's colormap to derive the
           foreground color used to draw the separator line. Keep in mind that
foreground the SimpleMenu widget will force all menu items to be the width of
           the widest entry. Thus, setting the width is generally not very
           important.

lineWidth  The width of the horizontal line that is to be displayed.

           If a bitmap is specified for this resource, the line will be
           stippled through it. This allows the menu separator to be rendered
stipple    as something more exciting than just a line. For instance, if you
           define a stipple that is a chain link, then your menu separators
           will look like chains.

Chapter 5. Text Widgets

Table of Contents

Text Widget for Users

    Default Key Bindings
    Search and Replace
    File Insertion
    Text Selections for Users

Text Widget Actions

    Cursor Movement Actions\fP
    Delete Actions
    Selection Actions
    The New Line Actions
    Kill and Actions
    Miscellaneous Actions
    Text Selections for Application Programmers

Default Translation Bindings
Text Functions

    Selecting Text
    Unhighlighting Text
    Getting Current Text Selection
    Replacing Text
    Searching for Text
    Redisplaying Text
    Resources Convenience Routines

Customizing the Text Widget
Text Widget

    Resources

TextSink Object

    Resources
    Subclassing the TextSink

TextSrc Object

    Resources
    Subclassing the TextSrc

Ascii Sink Object and Multi Sink Object

    Resources

Ascii Source Object and Multi Source Object

    Resources
    Convenience Routines

Ascii Text Widget

    Resources

The Text widget provides a window that will allow an application to display and
edit one or more lines of text. Options are provided to allow the user to add
Scrollbars to its window, search for a specific string, and modify the text in
the buffer.

The Text widget is made up of a number of pieces; it was modularized to ease
customization. The AsciiText widget class (actually not limited to ASCII but so
named for compatibility) is be general enough to most needs. If more
flexibility, special features, or extra functionality is needed, they can be
added by implementing a new TextSource or TextSink, or by subclassing the Text
Widget (See Section 5.8 for customization details.)

The words insertion point are used in this chapter to refer to the text caret.
This is the symbol that is displayed between two characters in the file. The
insertion point marks the location where any new characters will be added to
the file. To avoid confusion the pointer cursor will always be referred to as
the pointer.

The text widget supports three edit modes, controlling the types of
modifications a user is allowed to make:

  * Append-only

  * Editable

  * Read-only

Read-only mode does not allow the user or the programmer to modify the text in
the widget. While the entire string may be reset in read-only mode with
XtSetValues, it cannot be modified via with XawTextReplace. Append-only and
editable modes allow the text at the insertion point to be modified. The only
difference is that text may only be added to or removed from the end of a
buffer in append-only mode.

Text Widget for Users

The Text widget provides many of the common keyboard editing commands. These
commands allow users to move around and edit the buffer. If an illegal
operation is attempted, (such as deleting characters in a read-only text
widget), the X server will beep.

Default Key Bindings

The default key bindings are patterned after those in the EMACS text editor:



Ctrl-a  Beginning Of Line       Meta-b  Backward Word
Ctrl-b  Backward Character      Meta-f  Forward Word
Ctrl-d  Delete Next Character   Meta-i  Insert File
Ctrl-e  End Of Line     Meta-k  Kill To End Of Paragraph
Ctrl-f  Forward Character       Meta-q  Form Paragraph
Ctrl-g  Multiply Reset  Meta-v  Previous Page
Ctrl-h  Delete Previous Character       Meta-y  Insert Current Selection
Ctrl-j  Newline And Indent      Meta-z  Scroll One Line Down
Ctrl-k  Kill To End Of Line     Meta-d  Delete Next Word
Ctrl-l  Redraw Display  Meta-D  Kill Word
Ctrl-m  Newline Meta-h  Delete Previous Word
Ctrl-n  Next Line       Meta-H  Backward Kill Word
Ctrl-o  Newline And Backup      Meta-<  Beginning Of File
Ctrl-p  Previous Line   Meta->  End Of File
Ctrl-r  Search/Replace Backward Meta-]  Forward Paragraph
Ctrl-s  Search/Replace Forward  Meta-[  Backward Paragraph
Ctrl-t  Transpose Characters
Ctrl-u  Multiply by 4   Meta-Delete     Delete Previous Word
Ctrl-v  Next Page       Meta-Shift Delete       Kill Previous Word
Ctrl-w  Kill Selection  Meta-Backspace  Delete Previous Word
Ctrl-y  Unkill  Meta-Shift Backspace    Kill Previous Word
Ctrl-z  Scroll One Line Up
Ctrl-\\ Reconnect to input method
Kanji   Reconnect to input method

In addition, the pointer may be used to cut and paste text:



        Button 1 Down   Start Selection
        Button 1 Motion Adjust Selection
        Button 1 Up     End Selection (cut)

        Button 2 Down   Insert Current Selection (paste)

        Button 3 Down   Extend Current Selection
        Button 3 Motion Adjust Selection
        Button 3 Up     End Selection (cut)


Since all of these key and pointer bindings are set through the translations
and resource manager, the user and the application programmer can modify them
by changing the Text widget's translations resource.

Search and Replace

The Text widget provides a search popup that can be used to search for a string
within the current Text widget. The popup can be activated by typing either 
Control-r or Control-s. If Control-s is used the search will be forward in the
file from the current location of the insertion point; if Control-r is used the
search will be backward. The activated popup is placed under the pointer. It
has a number of buttons that allow both text searches and text replacements to
be performed.

At the top of the search popup are two toggle buttons labeled backward and 
forward. One of these buttons will always be highlighted; this is the direction
in which the search will be performed. The user can change the direction at any
time by clicking on the appropriate button.

Directly under the buttons there are two text areas, one labeled Search for:
and the other labeled Replace with:. If this is a read-only Text widget the 
Replace with: field will be insensitive and no replacements will be allowed.
After each of these labels will be a text field. This field will allow the user
to enter a string to search for and the string to replace it with. Only one of
these text fields will have a window border around it; this is the active text
field. Any key presses that occur when the focus in in the search popup will be
directed to the active text field. There are also a few special key sequences:



Carriage Return:        Execute the action, and pop down the search widget.
Tab:    Execute the action, then move to the next field.
Shift Carriage Return:  Execute the action, then move to the next field.
Control-q Tab:  Enter a Tab into a text field.
Control-c:      Pop down the search popup.

Using these special key sequences should allow simple searches without ever
removing one's hands from the keyboard.

Near the bottom of the search popup is a row of buttons. These buttons allow
the same actions to to be performed as the key sequences, but the buttons will
leave the popup active. This can be quite useful if many searches are being
performed, as the popup will be left on the display. Since the search popup is
a transient window, it may be picked up with the window manager and pulled off
to the side for use at a later time.

Search     Search for the specified string.

           Replace the currently highlighted string with the string in the 
Replace    Replace with text field, and move onto the next occurrence of the 
           Search for text field. The functionality is commonly referred to as
           query-replace.

           Replace all occurrences of the search string with the replace string
ReplaceAll from the current insertion point position to the end (or beginning)
           of the file. There is no key sequence to perform this action.

ReplaceAll Remove the search popup from the screen.

Finally, when international resource is true, there may be a pre-edit buffer
below the button row, for composing input. Its presence is determined by the X
locale in use and the VendorShell's preeditType resource.

The widget hierarchy for the search popup is show below, all widgets are listed
by class and instance name.

Text  <name of Text widget>
        TransientShell  search
                Form  form
                        Label label1
                        Label  label2
                        Toggle  backwards
                        Toggle  forwards
                        Label  searchLabel
                        Text  searchText
                        Label  replaceLabel
                        Text  replaceText
                        Command  search
                        Command  replaceOne
                        Command  replaceAll
                        Command  cancel

File Insertion

To insert a file into a text widget, type the key sequence Meta-i, which will
activate the file insert popup. This popup will appear under the pointer, and
any text typed while the focus is in this popup will be redirected to the text
field used for the filename. When the desired filename has been entered, click
on Insert File, or type Carriage Return. The named file will then be inserted
in the text widget beginning at the insertion point position. If an error
occurs when opening the file, an error message will be printed, prompting the
user to enter the filename again. The file insert may be aborted by clicking on
Cancel. If Meta-i is typed at a text widget that is read-only, it will beep, as
no file insertion is allowed.

The widget hierarchy for the file insert popup is show below; all widgets are
listed by class and instance name.

Text  <name of Text widget>
        TransientShell  insertFile
                Form  form
                        Label  label
                        Text  text
                        Command  insert
                        Command  cancel

Text Selections for Users

The text widgets have a text selection mechanism that allows the user to copy
pieces of the text into the PRIMARY selection, and paste into the text widget
some text that another application (or text widget) has put in the PRIMARY
selection.

One method of selecting text is to press pointer button 1 on the beginning of
the text to be selected, drag the pointer until all of the desired text is
highlighted, and then release the button to activate the selection. Another
method is to click pointer button 1 at one end of the text to be selected, then
click pointer button 3 at the other end.

To modify a currently active selection, press pointer button 3 near either the
end of the selection that you want to adjust. This end of the selection may be
moved while holding down pointer button 3. When the proper area has been
highlighted release the pointer button to activate the selection.

The selected text may now be pasted into another application, and will remain
active until some other client makes a selection. To paste text that some other
application has put into the PRIMARY selection use pointer button 2. First
place the insertion point where you would like the text to be inserted, then
click and release pointer button 2.

Rapidly clicking pointer button 1 the following number of times will adjust the
selection as described.

Two   Select the word under the pointer. A word boundary is defined by the Text
      widget to be a Space, Tab, or Carriage Return.

Three Select the line under the pointer.

      Select the paragraph under the pointer. A paragraph boundary is defined
Four  by the text widget as two Carriage Returns in a row with only Spaces or
      Tabs between them.

Five  Select the entire text buffer.

To unset the text selection, click pointer button 1 without moving it.

Text Widget Actions

All editing functions are performed by translation manager actions that may be
specified through the translations resource in the Text widget.



Insert Point Movement     Delete
     forward-character         delete-next-character
     backward-character        delete-previous-character
     forward-word              delete-next-word
     backward-word             delete-previous-word
     forward-paragraph         delete-selection
     backward-paragraph
     beginning-of-line
     end-of-line          Selection
     next-line                 select-word
     previous-line             select-all
     next-page                 select-start
     previous-page             select-adjust
     beginning-of-file         select-end
     end-of-file               extend-start
     scroll-one-line-up        extend-adjust
     scroll-one-line-down      extend-end
                               insert-selection


Miscellaneous             New Line
     redraw-display            newline-and-indent
     insert-file               newline-and-backup
     insert-char               newline
     insert-string
     display-caret
     focus-in             Kill
     focus-in                  kill-word
     search                    backward-kill-word
     multiply                  kill-selection
     form-paragraph            kill-to-end-of-line
     transpose-characters      kill-paragraph
     no-op                     kill-to-end-of-paragraph
     XawWMProtocols
     reconnect-im

Most of the actions take no arguments, and unless otherwise noted you may
assume this to be the case.

Cursor Movement Actions\fP

forward-character()

                     These actions move the insert point forward or backward
backward-character() one character in the buffer. If the insert point is at the
                     end or beginning of a line this action will move the
                     insert point to the next (or previous) line.

forward-word()

                     These actions move the insert point to the next or
backward-word()      previous word boundary. A word boundary is defined as a
                     Space, Tab or Carriage Return.

forward-paragraph()

                     These actions move the insert point to the next or
backward-paragraph() previous paragraph boundary. A paragraph boundary is
                     defined as two Carriage Returns in a row with only Spaces
                     or Tabs between them.

beginning-of-line()

                     These actions move to the beginning or end of the current
end-of-line()        line. If the insert point is already at the end or
                     beginning of the line then no action is taken.

next-line()

                     These actions move the insert point up or down one line.
                     If the insert point is currently N characters from the
previous-line()      beginning of the line then it will be N characters from
                     the beginning of the next or previous line. If N is past
                     the end of the line, the insert point is placed at the end
                     of the line.

next-page()

                     These actions move the insert point up or down one page in
previous-page()      the file. One page is defined as the current height of the
                     text widget. The insert point is always placed at the
                     first character of the top line by this action.

beginning-of-file()

                     These actions place the insert point at the beginning or
end-of-file()        end of the current text buffer. The text widget is then
                     scrolled the minimum amount necessary to make the new
                     insert point location visible.

scroll-one-line-up()

                     These actions scroll the current text field up or down by
                     one line. They do not move the insert point. Other than
scroll-one-line-down the scrollbars this is the only way that the insert point
()                   may be moved off of the visible text area. The widget will
                     be scrolled so that the insert point is back on the screen
                     as soon as some other action is executed.

Delete Actions

delete-next-character()

                          These actions remove the character immediately before
delete-previous-character or after the insert point. If a Carriage Return is
()                        removed then the next line is appended to the end of
                          the current line.

delete-next-word()

                          These actions remove all characters between the
delete-previous-word()    insert point location and the next word boundary. A
                          word boundary is defined as a Space, Tab or Carriage
                          Return.

                          This action removes all characters in the current
delete-selection()        selection. The selection can be set with the
                          selection actions.

Selection Actions

                 This action selects the word in which the insert point is
select-word()    currently located. If the insert point is between words then
                 it will select the previous word.

select-all()     This action selects the entire text buffer.

                 This action sets the insert point to the current pointer
                 location (if triggered by a button event) or text cursor
                 location (if triggered by a key event). It will then begin a
select-start()   selection at this location. If many of these selection actions
                 occur quickly in succession then the selection count mechanism
                 will be invoked (see the section titled \fBText Selections for
                 Application Programmers\fP for details).

select-adjust()  This action allows a selection started with the select-start
                 action to be modified, as described above.

                 This action ends a text selection that began with the 
select-end(name  select-start action, and asserts ownership of the selection or
[,name,...])     selections specified. A name can be a selection (e.g.,
                 PRIMARY) or a cut buffer (e.g., CUT_BUFFER0). Note that case
                 is important. If no names are specified, PRIMARY is asserted.

                 This action finds the nearest end of the current selection,
extend-start()   and moves it to the current pointer location (if triggered by
                 a button event) or text cursor location (if triggered by a key
                 event).

extend-adjust()  This action allows a selection started with an extend-start
                 action to be modified.

                 This action ends a text selection that began with the 
extend-end(name  extend-start action, and asserts ownership of the selection or
[,name,...])     selections specified. A name can be a selection (e.g. PRIMARY)
                 or a cut buffer (e.g CUT_BUFFER0). Note that case is
                 important. If no names are given, PRIMARY is asserted.

                 This action retrieves the value of the first (left-most) named
insert-selection selection that exists or the cut buffer that is not empty and
(name[,name      inserts it into the Text widget at the current insert point
,...])           location. A name can be a selection (e.g. PRIMARY) or a cut
                 buffer (e.g CUT_BUFFER0). Note that case is important.

The New Line Actions

newline-and-indent This action inserts a newline into the text and adds spaces
()                 to that line to indent it to match the previous line.

newline-and-backup This action inserts a newline into the text after the insert
()                 point.

newline()          This action inserts a newline into the text before the
                   insert point.

Kill and Actions

kill-word()

                         These actions act exactly like the delete-next-word
backward-kill-word()     and delete-previous-word actions, but they stuff the
                         word that was killed into the kill buffer
                         (CUT_BUFFER_1).

kill-selection()         This action deletes the current selection and stuffs
                         the deleted text into the kill buffer (CUT_BUFFER_1).

                         This action deletes the entire line to the right of
kill-to-end-of-line()    the insert point position, and stuffs the deleted text
                         into the kill buffer (CUT_BUFFER_1).

                         This action deletes the current paragraph, if between
kill-paragraph()         paragraphs it deletes the paragraph above the insert
                         point, and stuffs the deleted text into the kill
                         buffer (CUT_BUFFER_1).

                         This action deletes everything between the current
kill-to-end-of-paragraph insert point location and the next paragraph boundary,
()                       and stuffs the deleted text into the kill buffer
                         (CUT_BUFFER_1).

Miscellaneous Actions

               This action recomputes the location of all the text lines on the
redraw-display display, scrolls the text to vertically center the line
()             containing the insert point on the screen, clears the entire
               screen, and redisplays it.

               This action activates the insert file popup. The filename option
insert-file([  specifies the default filename to put in the filename buffer of
filename])     the popup. If no filename is specified the buffer is empty at
               startup.

               This action may only be attached to a key event. When the
               international resource is false, this action calls XLookupString
               to translate the event into a (rebindable) Latin-1 character
insert-char()  (sequence) and inserts it into the text at the insert point.
               When the international resource is true, characters are passed
               to the input method via XwcLookupString, and any committed
               string returned is inserted into the text at the insert point.

               This action inserts each string into the text at the insert
               point location. Any string beginning with the characters "0x"
               followed by an even number of hexadecimal digits is interpreted
insert-string( as a hexadecimal constant and the corresponding string is
string[,string inserted instead. This hexadecimal string may represent up to 50
,...])         8-bit characters. When theinternational resource is true, a
               hexadecimal string is intrepeted as being in a multi-byte
               encoding, and a hexadecimal or regular string will result in an
               error message if it is not legal in the current locale.

               This action allows the insert point to be turned on and off. The
               state argument specifies the desired state of the insert point.
               This value may be any of the string values accepted for Boolean
               resources (e.g. on, True, off, False, etc.). If no arguments are
display-caret( specified, the default value is True. The when argument
state,when)    specifies, for EnterNotify or LeaveNotify events whether or not
               the focus field in the event is to be examined. If the second
               argument is not specified, or specified as something other than
               always then if the action is bound to an EnterNotify or
               LeaveNotify event, the action will be taken only if the focus
               field is True. An augmented binding that might be useful is:



     *Text.Translations: #override \\
          <FocusIn>:     display-caret(on) \\n\\
          <FocusOut>:     display-caret(off)

focus-in()

focus-out()          These actions do not currently do anything.

                     This action activates the search popup. The direction must
search(direction,[   be specified as either forward or backward. The string is
string])             optional and is used as an initial value for the Search
                     for: string. For further explanation of the search widget
                     see the section on Text Searches.

                     The multiply action allows the user to multiply the
                     effects of many of the text actions. Thus the following
                     action sequence multiply(10) delete-next-word() will
                     delete 10 words. It does not matter whether these actions
                     take place in one event or many events. Using the default
multiply(value)      translations the key sequence \fIControl-u, Control-d\fP
                     will delete 4 characters. Multiply actions can be chained,
                     thus \fImultiply(5) multiply(5)\fP is the same as multiply
                     (25). If the string reset is passed to the multiply action
                     the effects of all previous multiplies are removed and a
                     beep is sent to the display.

                     This action removes all the Carriage Returns from the
                     current paragraph and reinserts them so that each line is
form-paragraph()     as long as possible, while still fitting on the current
                     screen. Lines are broken at word boundaries if at all
                     possible. This action currently works only on Text widgets
                     that use ASCII text.

                     This action will swap the position of the character to the
transpose-characters left of the insert point with the character to the right
()                   of the insert point. The insert point will then be
                     advanced one character.

                     The no-op action makes no change to the text widget, and
no-op([action])      is mainly used to override translations. This action takes
                     one optional argument. If this argument is RingBell then a
                     beep is sent to the display.

                     This action is written specifically for the file insertion
                     and the search and replace dialog boxes. This action is
                     attached to those shells by the Text widget, in order to
                     handle ClientMessage events with the WM_PROTOCOLS atom in
                     the detail field. This action supports WM_DELETE_WINDOW on
                     the Text widget popups, and may support other window
XawWMProtocols([     manager protocols if necessary in the future. The popup
wm_protocol_name])   will be dismissed if the window manager sends a
                     WM_DELETE_WINDOW request and there are no parameters in
                     the action call, which is the default. The popup will also
                     be dismissed if the parameters include the string
                     ``wm_delete_window,'' and the event is a ClientMessage
                     event requesting dismissal or is not a ClientMessage
                     event. This action is not sensitive to the case of the
                     strings passed as parameters.

                     When the international resource is true, input is usually
                     passed to an input method, a separate process, for
                     composing. Sometimes the connection to this process gets
reconnect-im()       severed; this action will attempt to reconnect it. Causes
                     for severage include network trouble, and the user
                     explicitly killing one input method and starting a new
                     one. This action may also establish first connection when
                     the application is started before the input method.

Text Selections for Application Programmers

The default behavior of the text selection array is described in the section
called Text Selections for Users. To modify the selections a programmer must
construct a XawTextSelectType array (called the selection array), containing
the selections desired, and pass this as the new value for the selectionTypes
resource. The selection array may also be modified using the
XawTextSetSelectionArray function. All selection arrays must end with the value
XawselectNull. The selectionTypes resource has no converter registered and
cannot be modified through the resource manager.

The array contains a list of entries that will be called when the user attempts
to select text in rapid succession with the select-start action (usually by
clicking a pointer button). The first entry in the selection array will be used
when the select-start action is initially called. The next entry will be used
when select-start is called again, and so on. If a timeout value (1/10 of a
second) is exceeded, the the next select-start action will begin at the top of
the selection array. When XawselectNull is reached the array is recycled
beginning with the first element.

+--------------------------------------------------------------------------+
|   XawselectAll   |      Selects the contents of the entire buffer.       |
|------------------+-------------------------------------------------------|
|  XawselectChar   |Selects text characters as the pointer moves over them.|
|------------------+-------------------------------------------------------|
|  XawselectLine   |               Selects the entire line.                |
|------------------+-------------------------------------------------------|
|  XawselectNull   |       Indicates the end of the selection array.       |
|------------------+-------------------------------------------------------|
|XawselectParagraph|             Selects the entire paragraph.             |
|------------------+-------------------------------------------------------|
|XawselectPosition |         Selects the current pointer position.         |
|------------------+-------------------------------------------------------|
|  XawselectWord   |  Selects whole words as the pointer moves onto them.  |
+--------------------------------------------------------------------------+

The default selectType array is:

{XawselectPosition, XawselectWord, XawselectLine, XawselectParagraph, XawselectAll, XawselectNull}

The selection array is not copied by the text widgets. The application must
allocate space for the array and cannot deallocate or change it until the text
widget is destroyed or until a new selection array is set.

Default Translation Bindings

The following translations are defaults built into every Text widget. They can
be overridden, or replaced by specifying a new value for the Text widget's
translations resource.



     Ctrl<Key>A:     beginning-of-line() \\n\\
     Ctrl<Key>B:     backward-character() \\n\\
     Ctrl<Key>D:     delete-next-character() \\n\\
     Ctrl<Key>E:     end-of-line() \\n\\
     Ctrl<Key>F:     forward-character() \\n\\
     Ctrl<Key>G:     multiply(Reset) \\n\\
     Ctrl<Key>H:     delete-previous-character() \\n\\
     Ctrl<Key>J:     newline-and-indent() \\n\\
     Ctrl<Key>K:     kill-to-end-of-line() \\n\\
     Ctrl<Key>L:     redraw-display() \\n\\
     Ctrl<Key>M:     newline() \\n\\
     Ctrl<Key>N:     next-line() \\n\\
     Ctrl<Key>O:     newline-and-backup() \\n\\
     Ctrl<Key>P:     previous-line() \\n\\
     Ctrl<Key>R:     search(backward) \\n\\
     Ctrl<Key>S:     search(forward) \\n\\
     Ctrl<Key>T:     transpose-characters() \\n\\
     Ctrl<Key>U:     multiply(4) \\n\\
     Ctrl<Key>V:     next-page() \\n\\
     Ctrl<Key>W:     kill-selection() \\n\\
     Ctrl<Key>Y:     insert-selection(CUT_BUFFER1) \\n\\
     Ctrl<Key>Z:     scroll-one-line-up() \\n\\
     Ctrl<Key>\\:     reconnect-im() \\n\\
     Meta<Key>B:     backward-word() \\n\\
     Meta<Key>F:     forward-word() \\n\\
     Meta<Key>I:     insert-file() \\n\\
     Meta<Key>K:     kill-to-end-of-paragraph() \\n\\
     Meta<Key>Q:     form-paragraph() \\n\\
     Meta<Key>V:     previous-page() \\n\\
     Meta<Key>Y:     insert-selection(PRIMARY, CUT_BUFFER0) \\n\\
     Meta<Key>Z:     scroll-one-line-down() \\n\\
     :Meta<Key>d:     delete-next-word() \\n\\
     :Meta<Key>D:     kill-word() \\n\\
     :Meta<Key>h:     delete-previous-word() \\n\\
     :Meta<Key>H:     backward-kill-word() \\n\\
     :Meta<Key>\\<:     beginning-of-file() \\n\\
     :Meta<Key>\\>:     end-of-file() \\n\\
     :Meta<Key>]:     forward-paragraph() \\n\\
     :Meta<Key>[:     backward-paragraph() \\n\\
     ~Shift Meta<Key>Delete:          delete-previous-word() \\n\\
     \ Shift Meta<Key>Delete:          backward-kill-word() \\n\\
     ~Shift Meta<Key>Backspace:     delete-previous-word() \\n\\
     \ Shift Meta<Key>Backspace:     backward-kill-word() \\n\\
     <Key>Right:     forward-character() \\n\\
     <Key>Left:     backward-character() \\n\\
     <Key>Down:     next-line() \\n\\
     <Key>Up:     previous-line() \\n\\
     <Key>Delete:     delete-previous-character() \\n\\
     <Key>BackSpace:     delete-previous-character() \\n\\
     <Key>Linefeed:     newline-and-indent() \\n\\
     <Key>Return:     newline() \\n\\
     <Key>:          insert-char() \\n\\
     <Key>Kanji:     reconnect-im() \\n\\
     <FocusIn>:     focus-in() \\n\\
     <FocusOut>:     focus-out() \\n\\
     <Btn1Down>:     select-start() \\n\\
     <Btn1Motion>:     extend-adjust() \\n\\
     <Btn1Up>:     extend-end(PRIMARY, CUT_BUFFER0) \\n\\
     <Btn2Down>:     insert-selection(PRIMARY, CUT_BUFFER0) \\n\\
     <Btn3Down>:     extend-start() \\n\\
     <Btn3Motion>:     extend-adjust() \\n\\
     <Btn3Up>:     extend-end(PRIMARY, CUT_BUFFER0) \\n

Text Functions

The following functions are provided as convenience routines for use with the
Text widget. Although many of these actions can be performed by modifying
resources, these interfaces are frequently more efficient.

These data structures are defined in the Text widget's public header file, <X11
/Xaw/Text.h>.

typedef long XawTextPosition;

Character positions in the Text widget begin at 0 and end at n, where n is the
number of characters in the Text source widget.



typedef struct {
        int firstPos;
        int length;
        char *ptr;
        unsigned long format;
} XawTextBlock, *XawTextBlockPtr;

firstPos The first position, or index, to use within the ptr field. The value
         is commonly zero.

         The number of characters to be used from the ptr field. The number of
length   characters used is commonly the number of characters in ptr, and must
         not be greater than the length of the string in ptr.

ptr      Contains the string to be referenced by the Text widget.

         This flag indicates whether the data pointed to by ptr is char or
         wchar_t. When the associated widget has international set to false
format   this field must be XawFmt8Bit. When the associated widget has
         international set to true this field must be either XawFmt8Bit or
         XawFmtWide.

Note

Note: Previous versions of Xaw used FMT8BIT , which has been retained for
backwards compatibility. FMT8BIT is deprecated and will eventually be removed
from the implementation.

Selecting Text

To select a piece of text, use XawTextSetSelection :

void XawTextSetSelection(Widget w, XawTextPositionleft, right);

w     Specifies the Text widget.

left  Specifies the character position at which the selection begins.

right Specifies the character position at which the selection ends.

See section 5.4 for a description of XawTextPosition. If redisplay is enabled,
this function highlights the text and makes it the PRIMARY selection. This
function does not have any effect on CUT_BUFFER0.

Unhighlighting Text

To unhighlight previously highlighted text in a widget, use
XawTextUnsetSelection:

void XawTextUnsetSelection(Widget w);

w Specifies the Text widget.

Getting Current Text Selection

To retrieve the text that has been selected by this text widget use
XawTextGetSelectionPos:

void XawTextGetSelectionPos(Widget w, XawTextPosition*begin_return,
*end_return);

w            Specifies the Text widget.

begin_return Returns the beginning of the text selection.

end_return   Returns the end of the text selection.

See section 5.4 for a description of XawTextPosition. If the returned values
are equal, no text is currently selected.

Replacing Text

To modify the text in an editable Text widget use XawTextReplace:

int XawTextReplace(Widget w, XawTextPositionstart, end, XawTextBlock *text);

w     Specifies the Text widget.

start Specifies the starting character position of the text replacement.

end   Specifies the ending character position of the text replacement.

text  Specifies the text to be inserted into the file.

This function will not be able to replace text in read-only text widgets. It
will also only be able to append text to an append-only text widget.

See section 5.4 for a description of XawTextPosition and XawTextBlock.

This function may return the following values:

XawEditDone      The text replacement was successful.

XawPositionError The edit mode is XawtextAppend and start is not the position
                 of the last character of the source.

XawEditError     Either the Source was read-only or the range to be deleted is
                 larger than the length of the Source.

The XawTextReplace arguments start and end represent the text source character
positions for the existing text that is to be replaced by the text in the text
block. The characters from start up to but not including end are deleted, and
the characters specified on the text block are inserted in their place. If 
start and end are equal, no text is deleted and the new text is inserted after 
start.

Searching for Text

To search for a string in the Text widget, use XawTextSearch:

XawTextPosition XawTextSearch(Widget w, XawTextScanDirection dir, XawTextBlock*
text);

w    Specifies the Text widget.

dir  Specifies the direction to search in. Legal values are XawsdLeft and
     XawsdRight.

text Specifies a text block structure that contains the text to search for.

See section 5.4 for a description of XawTextPosition and XawTextBlock. The
XawTextSearch function will begin at the insertion point and search in the
direction specified for a string that matches the one passed in text. If the
string is found the location of the first character in the string is returned.
If the string could not be found then the value XawTextSearchError is returned.

Redisplaying Text

To redisplay a range of characters, use XawTextInvalidate:

void XawTextInvalidate(Widget w, XawTextPositionfrom, to);

w    Specifies the Text widget.

from Specifies the start of the text to redisplay.

to   Specifies the end of the text to redisplay.

See section 5.4 for a description of XawTextPosition. The XawTextInvalidate
function causes the specified range of characters to be redisplayed immediately
if redisplay is enabled or the next time that redisplay is enabled.

To enable redisplay, use XawTextEnableRedisplay:

void XawTextEnableRedisplay(Widget w);

w Specifies the Text widget.

The XawTextEnableRedisplay function flushes any changes due to batched updates
when XawTextDisableRedisplay was called and allows future changes to be
reflected immediately.

To disable redisplay while making several changes, use XawTextDisableRedisplay.

void XawTextDisableRedisplay(Widget w);

w Specifies the Text widget.

The XawTextDisableRedisplay function causes all changes to be batched until
either XawTextDisplay or XawTextEnableRedisplay is called.

To display batched updates, use XawTextDisplay:

void XawTextDisplay(Widget w);

w Specifies the Text widget.

The XawTextDisplay function forces any accumulated updates to be displayed.

Resources Convenience Routines

To obtain the character position of the left-most character on the first line
displayed in the widget (the value of the displayPosition resource), use
XawTextTopPosition.

XawTextPosition XawTextTopPosition(Widget w);

w Specifies the Text widget.

To assign a new selection array to a text widget use XawTextSetSelectionArray:

void XawTextSetSelectionArray(Widget w, XawTextSelectType* sarray);

w      Specifies the Text widget.

sarray Specifies a selection array as defined in the section called \fBText
       Selections for Application Programmers\fP.

Calling this function is equivalent to setting the value of the selectionTypes
resource.

To move the insertion point to the specified source position, use
XawTextSetInsertionPoint:

void XawTextSetInsertionPoint(Widget w, XawTextPosition position);

w        Specifies the Text widget.

position Specifies the new position for the insertion point.

See section 5.4 for a description of XawTextPosition. The text will be scrolled
vertically if necessary to make the line containing the insertion point
visible. Calling this function is equivalent to setting the insertPosition
resource.

To obtain the current position of the insertion point, use
XawTextGetInsertionPoint:

XawTextPosition XawTextGetInsertionPoint(Widget w);

w Specifies the Text widget.

See section 5.4 for a description of XawTextPosition. The result is equivalent
to retrieving the value of the insertPosition resource.

To replace the text source in the specified widget, use XawTextSetSource:

void XawTextSetSource(Widget w, Widget source, XawTextPosition position);

w        Specifies the Text widget.

source   Specifies the text source object.

position Specifies character position that will become the upper left hand
         corner of the displayed text. This is usually set to zero.

See section 5.4 for a description of XawTextPosition. A display update will be
performed if redisplay is enabled.

To obtain the current text source for the specified widget, use
XawTextGetSource:

Widget XawTextGetSource(Widget w);

w Specifies the Text widget.

This function returns the text source that this Text widget is currently using.

To enable and disable the insertion point, use XawTextDisplayCaret:

void XawTextDisplayCaret(Widget w, Boolean visible);

w       Specifies the Text widget.

visible Specifies whether or not the caret should be displayed.

If visible is False the insertion point will be disabled. The marker is
re-enabled either by setting visible to True, by calling XtSetValues, or by
executing the display-caret action routine.

Customizing the Text Widget

The remainder of this chapter will describe customizing the Text widget. The
Text widget may be customized by subclassing, or by creating new sources and
sinks. Subclassing is described in detail in Chapter 7; this section will
describe only those things that are specific to the Text widget. Attributes of
the Text widget base class and creating new sources and sinks will be
discussed.

The Text widget is made up of a number of different pieces, with the Text
widget as the base widget class. It and the AsciiText widget are the only true
"widgets" in the Text widget family. The other pieces (sources and sinks) are X
Toolkit objects and have no window associated with them. No source or sink is
useful unless assigned to a Text widget.

Each of the following pieces of the Text widget has a specific purpose, and
will be, or has been, discussed in detail in this chapter:

          This is the glue that binds everything else together. This widget
Text      reads the text data from the source, and displays the information in
          the sink. All translations and actions are handled in the Text widget
          itself.

          This object is responsible for displaying and clearing the drawing
TextSink  area. It also reports the configuration of the window that contains
          the drawing area. The TextSink does not have its own window; instead
          it does its drawing on the Text widget's window.

TextSrc   This object is responsible for reading, editing and searching through
          the text buffer.

          This object is a subclass of the TextSink and knows how to display
AsciiSink ASCII text. Support has been added to display any 8-bit character
          set, given the font.

MultiSink This object is a subclass of the TextSink and knows how to display
          font sets.

AsciiSrc  This object is a subclass of the TextSrc and knows how to read
          strings and files.

          This object is a subclass of the TextSrc and knows how to read
MultiSrc  strings and multibyte files, converting them to wide characters based
          on locale.

          This widget is a subclass of the Text widget. When created, the
AsciiText AsciiText automatically creates and attaches either an AsciiSrc and
          AsciiSink, or a MultiSrc and MultiSink, to itself. The AsciiText
          provides the simplest interface to the Athena Text widgets.

Text Widget

Application Header file     <X11/Xaw/Text.h>
Class Header file           <X11/Xaw/TextP.h>
Class                       textWidgetClass
Class Name                  Text
Superclass                  Simple

The Text widget is the glue that binds all the other pieces together, it
maintains the internal state of the displayed text, and acts as a mediator
between the source and sink.

This section lists the resources that are actually part of the Text widget, and
explains the functionality provided by each.

Resources

When creating a Text widget instance, the following resources are retrieved
from the argument list or from the resource database:

+-------------------------------------------------------------------------------------+
|         Name         |      Class      |       Type       |Notes|   Default Value   |
|----------------------+-----------------+------------------+-----+-------------------|
|     accelerators     |  Accelerators   | AcceleratorTable |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|     Boolean      |  D  |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|       autoFill       |    AutoFill     |     Boolean      |     |       False       |
|----------------------+-----------------+------------------+-----+-------------------|
|      background      |   Background    |      Pixel       |     |XtDefaultBackground|
|----------------------+-----------------+------------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |      Pixmap      |     |XtUnspecifiedPixmap|
|----------------------+-----------------+------------------+-----+-------------------|
|     borderColor      |   BorderColor   |      Pixel       |     |XtDefaultForeground|
|----------------------+-----------------+------------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |      Pixmap      |     |XtUnspecifiedPixmap|
|----------------------+-----------------+------------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |    Dimension     |     |         1         |
|----------------------+-----------------+------------------+-----+-------------------|
|     bottomMargin     |     Margin      |     Position     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|       colormap       |    Colormap     |     Colormap     |     | Parent's Colormap |
|----------------------+-----------------+------------------+-----+-------------------|
|        cursor        |     Cursor      |      Cursor      |     |     XC_xterm      |
|----------------------+-----------------+------------------+-----+-------------------|
|      cursorName      |     Cursor      |      String      |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|        depth         |      Depth      |       int        |  C  |  Parent's Depth   |
|----------------------+-----------------+------------------+-----+-------------------|
|   destroyCallback    |    Callback     |  XtCallbackList  |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|     displayCaret     |     Output      |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|   displayPosition    |  TextPosition   | XawTextPosition  |     |         0         |
|----------------------+-----------------+------------------+-----+-------------------|
|        height        |     Height      |    Dimension     |  A  |   Font height +   |
|                      |                 |                  |     |      margins      |
|----------------------+-----------------+------------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |      Pixmap      |     |    GreyPixmap     |
|----------------------+-----------------+------------------+-----+-------------------|
|    insertPosition    |  TextPosition   |       int        |     |         0         |
|----------------------+-----------------+------------------+-----+-------------------|
|      leftMargin      |     Margin      |     Position     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|     pointerColor     |   Foreground    |      Pixel       |     |XtDefaultForeground|
|----------------------+-----------------+------------------+-----+-------------------|
|pointerColorBackground|   Background    |      Pixel       |     |XtDefaultBackground|
|----------------------+-----------------+------------------+-----+-------------------|
|        resize        |     Resize      |XawTextResizeMode |     |XawtextResizeNever |
|----------------------+-----------------+------------------+-----+-------------------|
|     rightMargin      |     Margin      |     Position     |     |         4         |
|----------------------+-----------------+------------------+-----+-------------------|
|        screen        |     Screen      |     Pointer      |  R  |  Parent's Screen  |
|----------------------+-----------------+------------------+-----+-------------------|
|   scrollHorizontal   |     Scroll      |    ScrollMode    |     |XawtextScrollNever |
|----------------------+-----------------+------------------+-----+-------------------|
|    scrollVertical    |     Scroll      |XawTextScrollMode |     |XawtextScrollNever |
|----------------------+-----------------+------------------+-----+-------------------|
|     selectTypes      |   SelectTypes   |XawTextSelectType*|     |     See above     |
|----------------------+-----------------+------------------+-----+-------------------|
|      sensitive       |    Sensitive    |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|       textSink       |    TextSink     |      Widget      |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|      textSource      |   TextSource    |      Widget      |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|      topMargin       |     Margin      |     Position     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|     translations     |  Translations   | TranslationTable |     |     See above     |
|----------------------+-----------------+------------------+-----+-------------------|
|  unrealizeCallback   |    Callback     |  XtCallbackList  |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|        width         |      Width      |    Dimension     |     |        100        |
|----------------------+-----------------+------------------+-----+-------------------|
|         wrap         |      Wrap       |     WrapMode     |     | XawtextWrapNever  |
|----------------------+-----------------+------------------+-----+-------------------|
|          x           |    Position     |     Position     |     |         0         |
|----------------------+-----------------+------------------+-----+-------------------|
|          y           |    Position     |     Position     |     |         0         |
+-------------------------------------------------------------------------------------+

TextSink Object



Application Header file <X11/Xaw/TextSink.h>

Class Header file       <X11/Xaw/TextSinkP.h>

Class           textSinkObjectClass

Class Name      TextSink

Superclass      Object

The TextSink object is the root object for all text sinks. Any new text sink
objects should be subclasses of the TextSink Object. The TextSink Class
contains all methods that the Text widget expects a text sink to export.

Since all text sinks will have some resources in common, the TextSink defines a
few new resources.

Resources

When creating an TextSink object instance, the following resources are
retrieved from the argument list or from the resource database:

+-------------------------------------------------------------------+
|     Name      |  Class   |     Type     |Notes|   Default Value   |
|---------------+----------+--------------+-----+-------------------|
|  background   |Background|    Pixel     |     |XtDefaultBackground|
|---------------+----------+--------------+-----+-------------------|
|destroyCallback| Callback |XtCallbackList|     |       NULL        |
|---------------+----------+--------------+-----+-------------------|
|  foreground   |Foreground|    Pixel     |     |XtDefaultForeground|
|---------------+----------+--------------+-----+-------------------|
|       _       |          |              |     |                   |
+-------------------------------------------------------------------+

Subclassing the TextSink

The only purpose of the TextSink Object is to be subclassed. It contains the
minimum set of class methods that all text sinks must have. While all may be
inherited, the direct descendant of TextSink must specify some of them as
TextSink does contain enough information to be a valid text sink by itself. Do
not try to use the TextSink as a valid sink for the Text widget; it is not
intended to be used as a sink by itself.

+---------------------------------------------------------------------------------+
|    Function     |       Inherit with       |      Public Interface      | must  |
|                 |                          |                            |specify|
|-----------------+--------------------------+----------------------------+-------|
|   DisplayText   |   XtInheritDisplayText   |   XawTextSinkDisplayText   |  yes  |
|-----------------+--------------------------+----------------------------+-------|
|  InsertCursor   |  XtInheritInsertCursor   |  XawTextSinkInsertCursor   |  yes  |
|-----------------+--------------------------+----------------------------+-------|
|ClearToBackground|XtInheritClearToBackground|XawTextSinkClearToBackground|  no   |
|-----------------+--------------------------+----------------------------+-------|
|  FindPosition   |  XtInheritFindPosition   |  XawTextSinkFindPosition   |  yes  |
|-----------------+--------------------------+----------------------------+-------|
|  FindDistance   |  XtInheritFindDistance   |  XawTextSinkFindDistance   |  yes  |
|-----------------+--------------------------+----------------------------+-------|
|     Resolve     |     XtInheritResolve     |     XawTextSinkResolve     |  yes  |
|-----------------+--------------------------+----------------------------+-------|
|    MaxLines     |    XtInheritMaxLines     |    XawTextSinkMaxLines     |  no   |
|-----------------+--------------------------+----------------------------+-------|
|    MaxHeight    |    XtInheritMaxHeight    |    XawTextSinkMaxHeight    |  no   |
|-----------------+--------------------------+----------------------------+-------|
|     SetTabs     |     XtInheritSetTabs     |     XawTextSinkSetTabs     |  no   |
|-----------------+--------------------------+----------------------------+-------|
| GetCursorBounds | XtInheritGetCursorBounds | XawTextSinkGetCursorBounds |  yes  |
+---------------------------------------------------------------------------------+

Displaying Text

To display a section of the text buffer contained in the text source use the
function DisplayText:

void DisplayText(Widget w, Positionx, y, XawTextPositionpos1, pos2, Boolean
highlight);

w         Specifies the TextSink object.

x         Specifies the x location to start drawing the text.

y         Specifies the y location to start drawing text.

pos1      Specifies the location within the text source of the first character
          to be printed.

pos2      Specifies the location within the text source of the last character
          to be printed.

highlight Specifies whether or not to paint the text region highlighted.

The Text widget will only pass one line at a time to the text sink, so this
function does not need to know how to line feed the text. It is acceptable for
this function to just ignore Carriage Returns. x and y denote the upper left
hand corner of the first character to be displayed.

Displaying the Insert Point

The function that controls the display of the text cursor is InsertCursor. This
function will be called whenever the text widget desires to change the state
of, or move the insert point.

void InsertCursor(Widget w, Positionx, y, XawTextInsertState state);

w     Specifies the TextSink object.

x     Specifies the x location of the cursor in Pixels.

y     Specifies the y location of the cursor in Pixels.

state Specifies the state of the cursor, may be one of XawisOn or XawisOff.

X and y denote the upper left hand corner of the insert point.

Clearing Portions of the Text window

To clear a portion of the Text window to its background color, the Text widget
will call ClearToBackground. The TextSink object already defines this function
as calling XClearArea on the region passed. This behavior will be used if you
specify XtInheritClearToBackground for this method.

void ClearToBackground(Widget w, Positionx, y, Dimensionwidth, height);

w      Specifies the TextSink object.

x      Specifies the x location, in pixels, of the Region to clear.

y      Specifies the y location, in pixels, of the Region to clear.

width  Specifies the width, in pixels, of the Region to clear.

height Specifies the height, in pixels, of the Region to clear.

X and y denote the upper left hand corner of region to clear.

Finding a Text Position Given Pixel Values

To find the text character position that will be rendered at a given x location
the Text widget uses the function FindPosition:

void FindPosition(Widget w, XawTextPosition fromPos, intfromX, width, Boolean
stopAtWordBreak, XawTextPosition *pos_return, int*width_return,
*height_return);

w               Specifies the TextSink object.

                Specifies a reference position, usually the first character in
fromPos         this line. This character is always to the left of the desired
                character location.

                Specifies the distance that the left edge of fromPos is from
fromX           the left edge of the window. This is the reference x location
                for the reference position.

width           Specifies the distance, in pixels, from the reference position
                to the desired character position.

stopAtWordBreak Specifies whether or not the position that is returned should
                be forced to be on a word boundary.

                Returns the character position that corresponds to the location
pos_return      that has been specified, or the work break immediately to the
                left of the position if stopAtWordBreak is True.

width_return    Returns the actual distance between fromPos and pos_return.

height_return   Returns the maximum height of the text between fromPos and 
                pos_return.

This function need make no attempt to deal with line feeds. The text widget
will only call it one line at a time.

Another means of finding a text position is provided by the Resolve function:

void Resolve(Widget w, XawTextPosition fromPos, intfromX, width,
XawTextPosition *pos_return);

w          Specifies the TextSink object.

           Specifies a reference position, usually the first character in this
fromPos    line. This character is always to the left of the desired character
           location.

           Specifies the distance that the left edge of fromPos is from the
fromX      left edge of the window. This is the reference x location for the
           reference position.

width      Specifies the distance, in pixels, from the reference position to
           the desired character position.

           Returns the character position that corresponds to the location that
pos_return has been specified, or the word break immediately to the left if 
           stopAtWordBreak is True.

This function need make no attempt to deal with line feeds. The text widget
will only call it one line at a time. This is a more convenient interface to
the FindPosition function, and provides a subset of its functionality.

Finding the Distance Between two Text Positions

To find the distance in pixels between two text positions on the same line use
the function FindDistance.

void FindDistance(Widget w, XawTextPositionfromPos, toPos, int fromX,
XawTextPosition *pos_return, int*width_return, *height_return);

w             Specifies the TextSink object.

fromPos       Specifies the text buffer position, in characters, of the first
              position.

              Specifies the distance that the left edge of fromPos is from the
fromX         left edge of the window. This is the reference x location for the
              reference position.

toPos         Specifies the text buffer position, in characters, of the second
              position.

resWidth      Return the actual distance between fromPos and pos_return.

              Returns the character position that corresponds to the actual
resPos        character position used for toPos in the calculations. This may
              be different than toPos, for example if fromPos and toPos are on
              different lines in the file.

height_return Returns the maximum height of the text between fromPos and 
              pos_return.

This function need make no attempt to deal with line feeds. The Text widget
will only call it one line at a time.

Finding the Size of the Drawing area

To find the maximum number of lines that will fit into the current Text widget,
use the function MaxLines. The TextSink already defines this function to
compute the maximum number of lines by using the height of font.

int MaxLines(Widget w, Dimension height);

w      Specifies the TextSink object.

height Specifies the height of the current drawing area.

Returns the maximum number of lines that will fit in height.

To find the height required for a given number of text lines, use the function
MaxHeight. The TextSink already defines this function to compute the maximum
height of the window by using the height of font.

int MaxHeight(Widget w, int lines);

w      Specifies the TextSink object.

height Specifies the height of the current drawing area.

Returns the height that will be taken up by the number of lines passed.

Setting the Tab Stops

To set the tab stops for a text sink use the SetTabs function. The TextSink
already defines this function to set the tab x location in pixels to be the
number of characters times the figure width of font.

void SetTabs(Widget w, inttab_count, *tabs);

w         Specifies the TextSink object.

tab_count Specifies the number of tabs passed in tabs.

tabs      Specifies the position, in characters, of the tab stops.

This function is responsible for the converting character positions passed to
it into whatever internal positions the TextSink uses for tab placement.

Getting the Insert Point's Size and Location

To get the size and location of the insert point use the GetCursorBounds
function.

void GetCursorBounds(Widget w, XRectangle *rect_return);

w           Specifies the TextSinkObject.

rect_return Returns the location and size of the insert point.

Rect will be filled with the current size and location of the insert point.

TextSrc Object

Application Header file <X11/Xaw/TextSrc.h>
Class Header file       <X11/Xaw/TextSrcP.h>
Class                   textSrcObjectClass
Class Name              TextSrc
Superclass              Object

The TextSrc object is the root object for all text sources. Any new text source
objects should be subclasses of the TextSrc Object. The TextSrc Class contains
all methods the Text widget expects a text source to export.

Since all text sources will have some resources in common the TextSrc defines a
few new resources.

Resources

When creating an TextSrc object instance, the following resources are retrieved
from the argument list or from the resource database:

+-----------------------------------------------------------+
|     Name      | Class  |     Type     |Notes|Default Value|
|---------------+--------+--------------+-----+-------------|
|destroyCallback|Callback|XtCallbackList|     |    NULL     |
|---------------+--------+--------------+-----+-------------|
|   editType    |EditType|   EditMode   |     |    NULL     |
+-----------------------------------------------------------+

Subclassing the TextSrc

The only purpose of the TextSrc Object is to be subclassed. It contains the
minimum set of class methods that all text sources must have. All class methods
of the TextSrc must be defined, as the Text widget uses them all. While all may
be inherited, the direct descendant of TextSrc must specify some of them as
TextSrc does not contain enough information to be a valid text source by
itself. Do not try to use the TextSrc as a valid source for the Text widget; it
is not intended to be used as a source by itself and bad things will probably
happen.

+--------------------------------------------------------------------------------+
|    Function    |      Inherit with       |      Public Interface       | must  |
|                |                         |                             |specify|
|----------------+-------------------------+-----------------------------+-------|
|      Read      |      XtInheritRead      |      XawTextSourceRead      |  yes  |
|----------------+-------------------------+-----------------------------+-------|
|    Replace     |    XtInheritReplace     |    XawTextSourceReplace     |  no   |
|----------------+-------------------------+-----------------------------+-------|
|      Scan      |      XtInheritScan      |      XawTextSourceScan      |  yes  |
|----------------+-------------------------+-----------------------------+-------|
|     Search     |     XtInheritSearch     |     XawTextSourceSearch     |  no   |
|----------------+-------------------------+-----------------------------+-------|
|  SetSelection  |  XtInheritSetSelection  |  XawTextSourceSetSelection  |  no   |
|----------------+-------------------------+-----------------------------+-------|
|ConvertSelection|XtInheritConvertSelection|XawTextSourceConvertSelection|  no   |
+--------------------------------------------------------------------------------+

Reading Text.

To read the text in a text source use the Read function:

XawTextPosition Read(Widget w, XawTextPosition pos, XawTextBlock *text_return,
int length);

w      Specifies the TextSrc object.

pos    Specifies the position of the first character to be read from the text
       buffer.

text   Returns the text read from the source.

length Specifies the maximum number of characters the TextSrc should return to
       the application in text_return.

This function returns the text position immediately after the characters read
from the text buffer. The function is not required to read length characters if
that many characters are in the file, it may break at any point that is
convenient to the internal structure of the source. It may take several calls
to Read before the desired portion of the text buffer is fully retrieved.

Replacing Text.

To replace or edit the text in a text buffer use the Replace function:

XawTextPosition Replace(Widget w, XawTextPositionstart, end, XawTextBlock
*text);

w     Specifies the TextSrc object.

start Specifies the position of the first character to be removed from the text
      buffer. This is also the location to begin inserting the new text.

end   Specifies the position immediately after the last character to be removed
      from the text buffer.

text  Specifies the text to be added to the text source.

This function can return any of the following values:

XawEditDone      The text replacement was successful.

XawPositionError The edit mode is XawtextAppend and start is not the last
                 character of the source.

XawEditError     Either the Source was read-only or the range to be deleted is
                 larger than the length of the Source.

The Replace arguments start and end represent the text source character
positions for the existing text that is to be replaced by the text in the text
block. The characters from start up to but not including end are deleted, and
the buffer specified by the text block is inserted in their place. If start and
end are equal, no text is deleted and the new text is inserted after start.

Scanning the TextSrc

To search the text source for one of the predefined boundary types use the Scan
function:

XawTextPosition Scan(Widget w, XawTextPosition position, XawTextScanType type,
XawTextScanDirection dir, int count, Boolean include);

w        Specifies the TextSrc object.

position Specifies the position to begin scanning the source.

         Specifies the type of boundary to scan for, may be one of:
type     XawstPosition, XawstWhiteSpace, XawstEOL, XawstParagraph, XawstAll.
         The exact meaning of these boundaries is left up to the individual
         text source.

dir      Specifies the direction to scan, may be either XawsdLeft to search
         backward, or XawsdRight to search forward.

count    Specifies the number of boundaries to scan for.

include  Specifies whether the boundary itself should be included in the scan.

The Scan function returns the position in the text source of the desired
boundary. It is expected to return a valid address for all calls made to it,
thus if a particular request is made that would take the text widget beyond the
end of the source it must return the position of that end.

Searching through a TextSrc

To search for a particular string use the Search function.

XawTextPosition Search(Widget w, XawTextPosition position, XawTextScanDirection
dir, XawTextBlock *text);

w        Specifies the TextSrc object.

position Specifies the position to begin the search.

dir      Specifies the direction to search, may be either XawsdLeft to search
         backward, or XawsdRight to search forward.

text     Specifies a text block containing the text to search for.

This function will search through the text buffer attempting to find a match
for the string in the text block. If a match is found in the direction
specified, then the character location of the first character in the string is
returned. If no text was found then XawTextSearchError is returned.

Text Selections

While many selection types are handled by the Text widget, text sources may
have selection types unknown to the Text widget. When a selection conversion is
requested by the X server the Text widget will first call the ConvertSelection
function, to attempt the selection conversion.

Boolean ConvertSelections(Widget w, Atom*selection,*target, *type, caddr_t
*value_return, unsignedlong *length_return, int *format_return);

w             Specifies the TextSrc object.

selection     Specifies the type of selection that was requested (e.g.
              PRIMARY).

              Specifies the type of the selection that has been requested,
target        which indicates the desired information about the selection (e.g.
              Filename, Text, Window).

              Specifies a pointer to the atom into which the property type of
type          the converted value of the selection is to be stored. For
              instance, either file name or text might have property type
              XA_STRING.

              Returns a pointer into which a pointer to the converted value of
              the selection is to be stored. The selection owner is responsible
value_return  for allocating this storage. The memory is considered owned by
              the toolkit, and is freed by XtFree when the Intrinsics selection
              mechanism is done with it.

length_return Returns a pointer into which the number of elements in value is
              to be stored. The size of each element is determined by format.

format_return Returns a pointer into which the size in bits of the data
              elements of the selection value is to be stored.

If this function returns True then the Text widget will assume that the source
has taken care of converting the selection, Otherwise the Text widget will
attempt to convert the selection itself.

If the source needs to know when the text selection is modified it should
define a SetSelection procedure:

void SetSelection(Widget w, XawTextPositionstart, end, Atom selection);

w         Specifies the TextSrc object.

start     Specifies the character position of the beginning of the new text
          selection.

end       Specifies the character position of the end of the new text
          selection.

selection Specifies the type of selection that was requested (e.g. PRIMARY).

Ascii Sink Object and Multi Sink Object



Application Header file <X11/Xaw/AsciiSink.h>

Class Header file       <X11/Xaw/AsciiSinkP.h>

Class           asciiSinkObjectClass

Class Name      AsciiSink

Superclass      TextSink

The AsciiSink or MultiSink object is used by a text widget to render the text.
Depending on its international resource, a AsciiText widget will create one or
the other of these when the AsciiText itself is created. Both types are nearly
identical; the following discussion applies to both, with MultiSink differences
noted only as they occur. The AsciiSink will display all printing characters in
an 8 bit font, along with handling Tab and Carriage Return. The name has been
left as ``AsciiSink'' for compatibility. \fIThe MultiSink will display all
printing characters in a font set, along with handling Tab and Carriage Return.
\fP The source object also reports the text window metrics to the text widgets.

Resources

When creating an AsciiSink object instance, the following resources are
retrieved from the argument list or from the resource database:

+----------------------------------------------------------------------+
|       Name       |  Class   |     Type     |Notes|   Default Value   |
|------------------+----------+--------------+-----+-------------------|
|    background    |Background|    Pixel     |     |XtDefaultBackground|
|------------------+----------+--------------+-----+-------------------|
| destroyCallback  | Callback |XtCallbackList|     |       NULL        |
|------------------+----------+--------------+-----+-------------------|
|displayNonprinting|  Output  |   Boolean    |     |       True        |
|------------------+----------+--------------+-----+-------------------|
|       echo       |  Output  |   Boolean    |     |       True        |
|------------------+----------+--------------+-----+-------------------|
|       font       |   Font   | XFontStruct* |     |   XtDefaultFont   |
|------------------+----------+--------------+-----+-------------------|
|     fontSet      | FontSet  |   XFontSet   |     | XtDefaultFontSet  |
|------------------+----------+--------------+-----+-------------------|
|    foreground    |Foreground|    Pixel     |     |XtDefaultForeground|
|------------------+----------+--------------+-----+-------------------|
|        _         |          |              |     |                   |
+----------------------------------------------------------------------+

This resource is retrieved by the AsciiSink instead of being copied from the
Text widget.

The text font to use when displaying the string. (This resource is present in
the AsciiSink, but not the MultiSink.)

The text font set to use when displaying the string. (This resource is present
in the MultiSink, but not the AsciiSink.)

Ascii Source Object and Multi Source Object



Application Header file <X11/Xaw/AsciiSrc.h> or <X11/Xaw/MultiSrc.h>

Class Header file       <X11/Xaw/AsciiSrcP.h> or  <X11/Xaw/MultiSrcP.h>

Class           asciiSrcObjectClass or multiSrcObjectClass

Class Name      AsciiSrc or MultiSrc

Superclass      TextSource

The AsciiSrc or MultiSrc object is used by a text widget to read the text from
a file or string in memory. Depending on its international resource, an
AsciiText widget will create one or the other of these when the AsciiText
itself is created. Both types are nearly identical; the following discussion
applies to both, with MultiSrc differences noted only as they occur.

The AsciiSrc understands all Latin1 characters plus Tab and Carriage Return. \
fIThe MultiSrc understands any set of character sets that the underlying X
implementation's internationalization handles.\fP

The AsciiSrc can be either of two types: XawAsciiFile or XawAsciiString.

AsciiSrc objects of type XawAsciiFile read the text from a file and store it
into an internal buffer. This buffer may then be modified, provided the text
widget is in the correct edit mode, just as if it were a source of type
XawAsciiString. Unlike R3 and earlier versions of the AsciiSrc, it is now
possible to specify an editable disk source. The file is not updated, however,
until a call to XawAsciiSave is made. When the source is in this mode the
useStringInPlace resource is ignored.

AsciiSrc objects of type XawAsciiString have the text buffer implemented as a
string. \fIMultiSrc objects of type XawAsciiString have the text buffer
implemented as a wide character string.\fP The string owner is responsible for
allocating and managing storage for the string.

In the default case for AsciiSrc objects of type XawAsciiString, the resource
useStringInPlace is false, and the widget owns the string. The initial value of
the string resource, and any update made by the application programmer to the
string resource with XtSetValues, is copied into memory private to the widget,
and managed internally by the widget. The application writer does not need to
worry about running out of buffer space (subject to the total memory available
to the application). The performance does not decay linearly as the buffer
grows large, as is necessarily the case when the text buffer is used in place.
The application writer must use XtGetValues to determine the contents of the
text buffer, which will return a copy of the widget's text buffer as it existed
at the time of the XtGetValues call. This copy is not affected by subsequent
updates to the text buffer, i.e., it is not updated as the user types input
into the text buffer. This copy is freed upon the next call to XtGetValues to
retrieve the string resource; however, to conserve memory, there is a
convenience routine, XawAsciiSourceFreeString, allowing the application
programmer to direct the widget to free the copy.

When the resource useStringInPlace is true and the AsciiSrc object is of type
XawAsciiString, the application is the string owner. The widget will take the
value of the string resource as its own text buffer, and the length resource
indicates the buffer size. In this case the buffer contents change as the user
types at the widget; it is not necessary to call XtGetValues on the string
resource to determine the contents of the buffer-it will simply return the
address of the application's implementation of the text buffer.

Resources

When creating an AsciiSrc object instance, the following resources are
retrieved from the argument list or from the resource database:

+-----------------------------------------------------------------------+
|      Name      |     Class      |     Type     |Notes| Default Value  |
|----------------+----------------+--------------+-----+----------------|
|    callback    |    Callback    |XtCallbackList|     |      NULL      |
|----------------+----------------+--------------+-----+----------------|
|dataCompression |DataCompression |   Boolean    |     |      True      |
|----------------+----------------+--------------+-----+----------------|
|destroyCallback |    Callback    |   Callback   |     |      NULL      |
|----------------+----------------+--------------+-----+----------------|
|    editType    |    EditType    |   EditMode   |     |  XawtextRead   |
|----------------+----------------+--------------+-----+----------------|
|     length     |     Length     |     Int      |  A  |length of string|
|----------------+----------------+--------------+-----+----------------|
|   pieceSize    |   PieceSize    |     Int      |     |     BUFSIZ     |
|----------------+----------------+--------------+-----+----------------|
|     string     |     String     |    String    |     |      NULL      |
|----------------+----------------+--------------+-----+----------------|
|      type      |      Type      |  AsciiType   |     | XawAsciiString |
|----------------+----------------+--------------+-----+----------------|
|useStringInPlace|UseStringInPlace|   Boolean    |     |     False      |
|----------------+----------------+--------------+-----+----------------|
|       _        |                |              |     |                |
+-----------------------------------------------------------------------+

Convenience Routines

The AsciiSrc has a few convenience routines that allow the application
programmer quicker or easier access to some of the commonly used functionality
of the AsciiSrc.

Conserving Memory

When the AsciiSrc widget is not in useStringInPlace mode space must be
allocated whenever the file is saved, or the string is requested with a call to
XtGetValues. This memory is allocated on the fly, and remains valid until the
next time a string needs to be allocated. You may save memory by freeing this
string as soon as you are done with it by calling XawAsciiSourceFreeString.

void XawAsciiSourceFreeString(Widget w);

w Specifies the AsciiSrc object.

This function will free the memory that contains the string pointer returned by
XtGetValues. This will normally happen automatically when the next call to
XtGetValues occurs, or when the widget is destroyed.

Saving Files

To save the changes made in the current text source into a file use
XawAsciiSave.

Boolean XawAsciiSave(Widget w);

w Specifies the AsciiSrc object.

XawAsciiSave returns True if the save was successful. It will update the file
named in the string resource. If the buffer has not been changed, no action
will be taken. This function only works on an AsciiSrc of type XawAsciiFile.

To save the contents of the current text buffer into a named file use
XawAsciiSaveAsFile.

Boolean XawAsciiSaveAsFile(Widget w, String name);

w    Specifies the AsciiSrc object.

name The name of the file to save the current buffer into.

This function returns True if the save was successful. XawAsciiSaveAsFile will
work with a buffer of either type XawAsciiString or type XawAsciiFile.

Seeing if the Source has Changed

To find out if the text buffer in an AsciiSrc object has changed since the last
time it was saved with XawAsciiSave or queried use XawAsciiSourceChanged.

Boolean XawAsciiSourceChanged(Widget w);

w Specifies the AsciiSrc object.

This function will return True if the source has changed since the last time it
was saved or queried. The internal change flag is reset whenever the string is
queried via XtGetValues or the buffer is saved via XawAsciiSave.

Ascii Text Widget



Application Header file <X11/Xaw/AsciiText.h>

ClassHeader file        <X11/Xaw/AsciiTextP.h>

Class           asciiTextWidgetClass

Class Name      Text

Superclass      Text
Sink Name       textSink
Source Name     textSource

For the ease of internationalization, the AsciiText widget class name has not
been changed, although it is actually able to support non-ASCII locales. The
AsciiText widget is really a collection of smaller parts. It includes the Text
widget itself, a ``Source'' (which supports memory management), and a ``Sink''
(which handles the display). There are currently two supported sources, the
AsciiSrc and MultiSrc, and two supported sinks, the AsciiSink and MultiSink.
Some of the resources listed below are not actually resources of the AsciiText,
but belong to the associated source or sink. This is is noted in the
explanation of each resource where it applies. When specifying these resources
in a resource file it is necessary to use *AsciiText*resource_name instead of 
*AsciiText.resource_name, since they actually belong to the children of the
AsciiText widget, and not the AsciiText widget itself. However, these resources
may be set directly on the AsciiText widget at widget creation time, or via
XtSetValues.

Resources

When creating an AsciiText widget instance, the following resources are
retrieved from the argument list or from the resource database:

+-------------------------------------------------------------------------------------+
|         Name         |      Class      |       Type       |Notes|   Default Value   |
|----------------------+-----------------+------------------+-----+-------------------|
|     accelerators     |  Accelerators   | AcceleratorTable |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|  ancestorSensitive   |AncestorSensitive|     Boolean      |  D  |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|       autoFill       |    AutoFill     |     Boolean      |     |       False       |
|----------------------+-----------------+------------------+-----+-------------------|
|      background      |   Background    |      Pixel       |     |XtDefaultBackground|
|----------------------+-----------------+------------------+-----+-------------------|
|   backgroundPixmap   |     Pixmap      |      Pixmap      |     |XtUnspecifiedPixmap|
|----------------------+-----------------+------------------+-----+-------------------|
|     borderColor      |   BorderColor   |      Pixel       |     |XtDefaultForeground|
|----------------------+-----------------+------------------+-----+-------------------|
|     borderPixmap     |     Pixmap      |      Pixmap      |     |XtUnspecifiedPixmap|
|----------------------+-----------------+------------------+-----+-------------------|
|     borderWidth      |   BorderWidth   |    Dimension     |     |         1         |
|----------------------+-----------------+------------------+-----+-------------------|
|     bottomMargin     |     Margin      |     Position     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|       callback       |    Callback     |  XtCallbackList  |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|       colormap       |    Colormap     |     Colormap     |     | Parent's Colormap |
|----------------------+-----------------+------------------+-----+-------------------|
|        cursor        |     Cursor      |      Cursor      |     |     XC_xterm      |
|----------------------+-----------------+------------------+-----+-------------------|
|      cursorName      |     Cursor      |      String      |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|   dataCompression    | DataCompression |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|        depth         |      Depth      |       int        |  C  |  Parent's Depth   |
|----------------------+-----------------+------------------+-----+-------------------|
|   destroyCallback    |    Callback     |  XtCallbackList  |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|     displayCaret     |     Output      |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|  displayNonprinting  |     Output      |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|   displayPosition    |  TextPosition   | XawTextPosition  |     |         0         |
|----------------------+-----------------+------------------+-----+-------------------|
|         echo         |     Output      |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|       editType       |    EditType     | XawTextEditType  |     |    XawtextRead    |
|----------------------+-----------------+------------------+-----+-------------------|
|         font         |      Font       |   XFontStruct*   |     |   XtDefaultFont   |
|----------------------+-----------------+------------------+-----+-------------------|
|       fontSet        |     FontSet     |     XFontSet     |     | XtDefaultFontSet  |
|----------------------+-----------------+------------------+-----+-------------------|
|      foreground      |   Foreground    |      Pixel       |     |XtDefaultForeground|
|----------------------+-----------------+------------------+-----+-------------------|
|        height        |     Height      |    Dimension     |  A  |   Font height +   |
|                      |                 |                  |     |      margins      |
|----------------------+-----------------+------------------+-----+-------------------|
|  insensitiveBorder   |   Insensitive   |      Pixmap      |     |    GreyPixmap     |
|----------------------+-----------------+------------------+-----+-------------------|
|    insertPosition    |  TextPosition   |       int        |     |         0         |
|----------------------+-----------------+------------------+-----+-------------------|
|    international     |  International  |     Boolean      |  C  |       False       |
|----------------------+-----------------+------------------+-----+-------------------|
|      leftMargin      |     Margin      |    Dimension     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|        length        |     Length      |       int        |  A  | length of string  |
|----------------------+-----------------+------------------+-----+-------------------|
|  mappedWhenManaged   |MappedWhenManaged|     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|      pieceSize       |    PieceSize    | XawTextPosition  |     |      BUFSIZ       |
|----------------------+-----------------+------------------+-----+-------------------|
|     pointerColor     |   Foreground    |      Pixel       |     |XtDefaultForeground|
|----------------------+-----------------+------------------+-----+-------------------|
|pointerColorBackground|   Background    |      Pixel       |     |XtDefaultBackground|
|----------------------+-----------------+------------------+-----+-------------------|
|        resize        |     Resize      |XawTextResizeMode |     |XawtextResizeNever |
|----------------------+-----------------+------------------+-----+-------------------|
|     rightMargin      |     Margin      |     Position     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|        screen        |     Screen      |      Screen      |  R  |  Parent's Screen  |
|----------------------+-----------------+------------------+-----+-------------------|
|   scrollHorizontal   |     Scroll      |XawTextScrollMode |     |XawtextScrollNever |
|----------------------+-----------------+------------------+-----+-------------------|
|    scrollVertical    |     Scroll      |XawTextScrollMode |     |XawtextScrollNever |
|----------------------+-----------------+------------------+-----+-------------------|
|     selectTypes      |   SelectTypes   |XawTextSelectType*|     |     See above     |
|----------------------+-----------------+------------------+-----+-------------------|
|      sensitive       |    Sensitive    |     Boolean      |     |       True        |
|----------------------+-----------------+------------------+-----+-------------------|
|        string        |     String      |      String      |     |       NULL        |
|----------------------+-----------------+------------------+-----+-------------------|
|       textSink       |    TextSink     |      Widget      |     |   An AsciiSink    |
|----------------------+-----------------+------------------+-----+-------------------|
|      textSource      |   TextSource    |      Widget      |     |    An AsciiSrc    |
|----------------------+-----------------+------------------+-----+-------------------|
|      topMargin       |     Margin      |     Position     |     |         2         |
|----------------------+-----------------+------------------+-----+-------------------|
|     translations     |  Translations   | TranslationTable |     |     See above     |
|----------------------+-----------------+------------------+-----+-------------------|
|         type         |      Type       |   XawAsciiType   |     |  XawAsciiString   |
|----------------------+-----------------+------------------+-----+-------------------|
|   useStringInPlace   |UseStringInPlace |     Boolean      |     |       False       |
|----------------------+-----------------+------------------+-----+-------------------|
|        width         |      Width      |    Dimension     |     |        100        |
|----------------------+-----------------+------------------+-----+-------------------|
|         wrap         |      Wrap       |     WrapMode     |     | XawtextWrapNever  |
|----------------------+-----------------+------------------+-----+-------------------|
|          x           |    Position     |     Position     |     |         0         |
|----------------------+-----------------+------------------+-----+-------------------|
|          y           |    Position     |     Position     |     |         0         |
+-------------------------------------------------------------------------------------+

Chapter 6. Composite and Constraint Widgets

Table of Contents

Box Widget

    Resources
    Layout Semantics

Dialog Widget

    Resources
    Constraint Resources
    Layout Semantics
    Automatically Created Children.
    Convenience Routines

Form Widget

    Resources
    Constraint Resources
    Layout Semantics
    Convenience Routines

Paned Widget

    Using the Paned Widget
    Resources
    Constraint Resources
    Layout Semantics
    Grip Translations
    Convenience Routines

Porthole Widget

    Resources
    Layout Semantics
    Porthole Callbacks

Tree Widget

    Resources
    Constraint Resources
    Layout Semantics
    Convenience Routines

Viewport Widget

    Resources
    Layout Semantics

These widgets may contain arbitrary widget children. They implement a policy
for the size and location of their children.

Box      This widget will pack its children as tightly as possible in
         non-overlapping rows.

Dialog   An implementation of a commonly used interaction semantic to prompt
         for auxiliary input from the user, such as a filename.

         A more sophisticated layout widget that allows the children to specify
Form     their positions relative to the other children, or to the edges of the
         Form.

         Allows children to be tiled vertically or horizontally. Controls are
Paned    also provided to allow the user to dynamically resize the individual
         panes.

Porthole Allows viewing of a managed child which is as large as, or larger than
         its parent, typically under control of a Panner widget.

Tree     Provides geometry management of widgets arranged in a directed,
         acyclic graph.

         Consists of a frame, one or two scrollbars, and an inner window. The
Viewport inner window can contain all the data that is to be displayed. This
         inner window will be clipped by the frame with the scrollbars
         controlling which section of the inner window is currently visible.

Note

The geometry management semantics provided by the X Toolkit give full control
of the size and position of a widget to the parent of that widget. While the
children are allowed to request a certain size or location, it is the parent
who makes the final decision. Many of the composite widgets here will deny any
geometry request from their children by default. If a child widget is not
getting the expected size or location, it is most likely the parent disallowing
a request, or implementing semantics slightly different than those expected by
the application programmer.

If the application wishes to change the size or location of any widget it
should make a call to XtSetValues. This will allow the widget to ask its parent
for the new size or location. As noted above the parent is allowed to refuse
this request, and the child must live with the result. If the application is
unable to achieve the desired semantics, then perhaps it should use a different
composite widget. Under no circumstances should an application programmer
resort to XtMoveWidget or XtResizeWidget; these functions are exclusively for
the use of Composite widget implementors.

For more information on geometry management consult the X Toolkit Intrinsics -
C Language Interface.

Box Widget




Application Header file <X11/Xaw/Box.h>

Class Header file       <X11/Xaw/BoxP.h>

Class           boxWidgetClass

Class Name      Box

Superclass      Composite


The Box widget provides geometry management of arbitrary widgets in a box of a
specified dimension. The children are rearranged when resizing events occur
either on the Box or its children, or when children are managed or unmanaged.
The Box widget always attempts to pack its children as tightly as possible
within the geometry allowed by its parent.

Box widgets are commonly used to manage a related set of buttons and are often
called ButtonBox widgets, but the children are not limited to buttons. The
Box's children are arranged on a background that has its own specified
dimensions and color.

Resources

When creating a Box widget instance, the following resources are retrieved from
the argument list or from the resource database:

+------------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |Notes|   Default Value   |
|-----------------+-----------------+----------------+-----+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   background    |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------+-----------------+----------------+-----+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |     |         1         |
|-----------------+-----------------+----------------+-----+-------------------|
|    children     |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    colormap     |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------+-----------------+----------------+-----+-------------------|
|      depth      |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------+-----------------+----------------+-----+-------------------|
| destroyCallback |    Callback     | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|     height      |     Height      |   Dimension    |  A  |    see Layout     |
|                 |                 |                |     |     Semantics     |
|-----------------+-----------------+----------------+-----+-------------------|
|     hSpace      |     HSpace      |   Dimension    |     |         4         |
|-----------------+-----------------+----------------+-----+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   numChildren   |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|   orientation   |   Orientation   |  Orientation   |     | XtorientVertical  |
|-----------------+-----------------+----------------+-----+-------------------|
|     screen      |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------+-----------------+----------------+-----+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|     vSpace      |     VSpace      |   Dimension    |     |         4         |
|-----------------+-----------------+----------------+-----+-------------------|
|  translations   |  Translations   |TranslationTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|      width      |      Width      |   Dimension    |  A  |    see Layout     |
|                 |                 |                |     |     Semantics     |
|-----------------+-----------------+----------------+-----+-------------------|
|        x        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        y        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        _        |                 |                |     |                   |
+------------------------------------------------------------------------------+

hSpace

            The amount of space, in pixels, to leave between the children. This
vSpace      resource specifies the amount of space left between the outermost
            children and the edge of the box.

            Specifies whether the preferred shape of the box (i.e. the result
            returned by the query_geometry class method) is tall and narrow
            XtorientVertical or short and wide XtorientHorizontal. When the Box
orientation is a child of a parent which enforces width constraints, it is
            usually better to specify XtorientVertical (the default). When the
            parent enforces height constraints, it is usually better to specify
            XtorientHorizontal.

Layout Semantics

Each time a child is managed or unmanaged, the Box widget will attempt to
reposition the remaining children to compact the box. Children are positioned
in order left to right, top to bottom. The packing algorithm used depends on
the orientation of the Box.

                   When the next child does not fit on the current row, a new
                   row is started. If a child is wider than the width of the
XtorientVertical   box, the box will request a larger width from its parent and
                   will begin the layout process from the beginning if a new
                   width is granted.

                   When the next child does not fit on the current row, the Box
XtorientHorizontal widens if possible (so as to keep children on a single row);
                   otherwise a new row is started.

After positioning all children, the Box widget attempts to shrink its own size
to the minimum dimensions required for the layout.

Dialog Widget




Application Header file <X11/Xaw/Dialog.h>

Class Header file       <X11/Xaw/DialogP.h>

Class           dialogWidgetClass

Class Name      Dialog

Superclass      Form


The Dialog widget implements a commonly used interaction semantic to prompt for
auxiliary input from a user. For example, you can use a Dialog widget when an
application requires a small piece of information, such as a filename, from the
user. A Dialog widget, which is simply a special case of the Form widget,
provides a convenient way to create a preconfigured form.

The typical Dialog widget contains three areas. The first line contains a
description of the function of the Dialog widget, for example, the string 
Filename:. The second line contains an area into which the user types input.
The third line can contain buttons that let the user confirm or cancel the
Dialog input. Any of these areas may be omitted by the application.

Resources

When creating a Dialog widget instance, the following resources are retrieved
from the argument list or the resource database:

+------------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |Notes|   Default Value   |
|-----------------+-----------------+----------------+-----+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   background    |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------+-----------------+----------------+-----+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |     |         1         |
|-----------------+-----------------+----------------+-----+-------------------|
|    children     |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    colormap     |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------+-----------------+----------------+-----+-------------------|
| defaultDistance |    Thickness    |      int       |     |         4         |
|-----------------+-----------------+----------------+-----+-------------------|
|      depth      |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------+-----------------+----------------+-----+-------------------|
| destroyCallback |    Callback     | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|                 |                 |                |     |  Enough space to  |
|     height      |     Height      |   Dimension    |  A  |    contain all    |
|                 |                 |                |     |     children      |
|-----------------+-----------------+----------------+-----+-------------------|
|      icon       |      Icon       |     Bitmap     |     |       None        |
|-----------------+-----------------+----------------+-----+-------------------|
|      label      |      Label      |     String     |     |      "label"      |
|-----------------+-----------------+----------------+-----+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   numChildren   |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|     screen      |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------+-----------------+----------------+-----+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|  translations   |  Translations   |TranslationTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|      value      |      Value      |     String     |     |  no value widget  |
|-----------------+-----------------+----------------+-----+-------------------|
|                 |                 |                |     |  Enough space to  |
|      width      |      Width      |   Dimension    |  A  |    contain all    |
|                 |                 |                |     |     children      |
|-----------------+-----------------+----------------+-----+-------------------|
|        x        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        y        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        _        |                 |                |     |                   |
+------------------------------------------------------------------------------+

icon  A pixmap image to be displayed immediately to the left of the Dialog
      widget's label.

label A string to be displayed at the top of the Dialog widget.

      An initial value for the string field that the user will enter text into.
      By default, no text entry field is available to the user. Specifying an
value initial value for value activates the text entry field. If string input
      is desired, but no initial value is to be specified then set this
      resource to "" (empty string).

Constraint Resources

Each child of the Dialog widget may request special layout resources be applied
to it. These constraint resources allow the Dialog widget's children to specify
individual layout requirements.

+--------------------------------------------------------------------+
|    Name     |  Class  |   Type    |Notes|      Default Value       |
|-------------+---------+-----------+-----+--------------------------|
|   bottom    |  Edge   |XawEdgeType|     |        XawRubber         |
|-------------+---------+-----------+-----+--------------------------|
|  fromHoriz  | Widget  |  Widget   |     |NULL (left edge of Dialog)|
|-------------+---------+-----------+-----+--------------------------|
|  fromVert   | Widget  |  Widget   |     |NULL (top edge of Dialog) |
|-------------+---------+-----------+-----+--------------------------|
|horizDistance|Thickness|    int    |     | defaultDistance resource |
|-------------+---------+-----------+-----+--------------------------|
|    left     |  Edge   |XawEdgeType|     |        XawRubber         |
|-------------+---------+-----------+-----+--------------------------|
|  resizable  | Boolean |  Boolean  |     |          FALSE           |
|-------------+---------+-----------+-----+--------------------------|
|    right    |  Edge   |XawEdgeType|     |        XawRubber         |
|-------------+---------+-----------+-----+--------------------------|
|     top     |  Edge   |XawEdgeType|     |        XawRubber         |
|-------------+---------+-----------+-----+--------------------------|
|vertDistance |Thickness|    int    |     | defaultDistance resource |
+--------------------------------------------------------------------+

bottom
left
right
top            What to do with this edge of the child when
               the parent is resized.  This resource may be
               any edgeType.  See Layout Semantics for
               details.

fromHoriz
fromVert       Which widget this child should be placed
               underneath (or to the right of).  If a value
               of NULL is specified then this widget will be
               positioned relative to the edge of the par-
               ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
               child and its left or upper neighbor.

resizable      If this resource is False then the parent
               widget will ignore all geometry request made
               by this child.  The parent may still resize
               this child itself, however.

Layout Semantics

The Dialog widget uses two different sets of layout seman- tics. One is used
when initially laying out the children. The other is used when the Dialog is
resized.

The first layout method uses the fromVert mand fromHoriz resources to place the
children of the Dialog. A single pass is made through the Dialog widget's
children in the order that they were created. Each child is then placed in the
Dialog widget below or to the right of the widget speci- fied by the fromVert
mand fromHoriz mresources. The distance the new child is placed from its left
or upper neighbor is determined by the horizDistance mand vertDistance
mresources. This implies some things about how the order of creation affects
the possible placement of the children. The Form widget registers a string to
widget converter which does not postpone conversion and does not cache
conversion results.

The second layout method is used when the Dialog is resized. It does not matter
what causes this resize, and it is possi- ble for a resize to happen before the
widget becomes visible (due to constraints imposed by the parent of the
Dialog). This layout method uses the bottom , top , left , and right resources.
These resources are used to determine what will happen to each edge of the
child when the Dialog is resized. If a value of XawChain <something> is
specified, the the edge of the child will remain a fixed distance from the 
chain edge of the Dialog. For example if XawChainLeft mis specified for the
right mresource of a child then the right edge of that child will remain a
fixed distance from the left edge of the Dialog widget. If a value of XawRubber
mis spec- ified, that edge will grow by the same percentage that the Dialog
grew. For instance if the Dialog grows by 50% the left edge of the child (if
specified as XawRubber mwill be 50% farther from the left edge of the Dialog).
One must be very careful when specifying these resources, for when they are
specified incorrectly children may overlap or completely occlude other children
when the Dialog widget is resized.

+-----------------------------------------------------------------------------+
|  Edge Type   |  Resource  |                   Description                   |
|              |    Name    |                                                 |
|--------------+------------+-------------------------------------------------|
|XawChainBottom|ChainBottom |  Edge remains a fixed distance from bottom of   |
|              |            |                     Dialog                      |
|--------------+------------+-------------------------------------------------|
| XawChainLeft | ChainLeft  |Edge remains a fixed distance from left of Dialog|
|--------------+------------+-------------------------------------------------|
|XawChainRight | ChainRight |   Edge remains a fixed distance from right of   |
|              |            |                     Dialog                      |
|--------------+------------+-------------------------------------------------|
| XawChainTop  |  ChainTop  |Edge remains a fixed distance from top of Dialog |
|--------------+------------+-------------------------------------------------|
|  XawRubber   |   Rubber   |     Edges will move a proportional distance     |
+-----------------------------------------------------------------------------+

Example

If you wish to force the Dialog to never resize one or more of its children
then set left and right to XawChainLeft and top and bottom to XawChainTop. This
will cause the child to remain a fixed distance from the top and left edges of
the Dialog, and to never resize.

Special Considerations

The Dialog widget automatically sets the top and bottom resources for all
Children that are subclasses of the Command widget, as well as the widget
children that are used to contain the label, value, and icon. This policy
allows the buttons at the bottom of the Dialog to interact correctly with the
predefined children, and makes it possible for a client to simply create and
manage a new Command button without having to specify its constraints.

The Dialog will also set fromLeft to the last button in the Dialog for each new
button added to the Dialog widget.

The automatically added constraints cannot be overridden, as they are policy
decisions of the Dialog widget. If a more flexible Dialog is desired, the
application is free to use the Form widget to create its own Dialog policy.

Automatically Created Children.

The Dialog uses Label widgets to contain the label and icon. These widgets are
named label and icon respectively. The Dialog value is contained in an
AsciiText widget whose name is value. Using XtNameToWidget the application can
change those resources associated with each of these widgets that are not
available through the Dialog widget itself.

Convenience Routines

To return the character string in the text field, use

String XawDialogGetValueString(Widget w);

w Specifies the Dialog widget.

This function returns a copy of the value string of the Dialog widget. This
string is allocated by the AsciiText widget and will remain valid and unchanged
until another call to XawDialogGetValueString or an XtGetValues call on the
value widget, when the string will be automatically freed, and a new string is
returned. This string may be freed earlier by calling the function
XawAsciiSourceFreeString.

To add a new button to the Dialog widget use XawDialogAddButton.

void XawDialogAddButton(Widget w, String name, XtCallbackProc func, XtPointer
client_data);

w           Specifies the Dialog widget.

name        Specifies the name of the new Command button to be added to the
            Dialog.

func        Specifies a callback function to be called when this button is
            activated. If NULL is specified then no callback is added.

client_data Specifies the client_data to be passed to the func.

This function is merely a shorthand for the code sequence:




{
        Widget button = XtCreateManagedWidget(name, commandWidgetClass, w, NULL, ZERO);
        XtAddCallback(button, XtNcallback, func, client_data);
}


Form Widget




Application Header file <X11/Xaw/Form.h>

Class Header file       <X11/Xaw/FormP.h>

Class           formWidgetClass

Class Name      Form

Superclass      Constraint


The Form widget can contain an arbitrary number of children or subwidgets. The
Form provides geometry management for its children, which allows individual
control of the position of each child. Any combination of children can be added
to a Form. The initial positions of the children may be computed relative to
the positions of previously created children. When the Form is resized, it
computes new positions and sizes for its children. This computation is based
upon information provided when a child is added to the Form.

The default width of the Form is the minimum width needed to enclose the
children after computing their initial layout, with a margin of defaultDistance
at the right and bottom edges. If a width and height is assigned to the Form
that is too small for the layout, the children will be clipped by the right and
bottom edges of the Form.

Resources

When creating a Form widget instance, the following resources are retrieved
from the argument list or from the resource database:

+------------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |Notes|   Default Value   |
|-----------------+-----------------+----------------+-----+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   background    |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------+-----------------+----------------+-----+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |     |         1         |
|-----------------+-----------------+----------------+-----+-------------------|
|    children     |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    colormap     |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------+-----------------+----------------+-----+-------------------|
| defaultDistance |    Thickness    |      int       |     |         4         |
|-----------------+-----------------+----------------+-----+-------------------|
|      depth      |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------+-----------------+----------------+-----+-------------------|
| destroyCallback |    Callback     | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|                 |                 |                |     |  Enough space to  |
|     height      |     Height      |   Dimension    |  A  |    contain all    |
|                 |                 |                |     |     children      |
|-----------------+-----------------+----------------+-----+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   numChildren   |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|     screen      |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------+-----------------+----------------+-----+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|  translations   |  Translations   |TranslationTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|                 |                 |                |     |  Enough space to  |
|      width      |      Width      |   Dimension    |  A  |    contain all    |
|                 |                 |                |     |     children      |
|-----------------+-----------------+----------------+-----+-------------------|
|        x        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        y        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        _        |                 |                |     |                   |
+------------------------------------------------------------------------------+

Constraint Resources

Each child of the Form widget may request special layout resources be applied
to it. These constraint resources allow the Form widget's children to specify
individual layout requirements.

+------------------------------------------------------------------+
|    Name     |  Class  |   Type    |Notes|     Default Value      |
|-------------+---------+-----------+-----+------------------------|
|   bottom    |  Edge   |XawEdgeType|     |       XawRubber        |
|-------------+---------+-----------+-----+------------------------|
|  fromHoriz  | Widget  |  Widget   |     |NULL (left edge of Form)|
|-------------+---------+-----------+-----+------------------------|
|  fromVert   | Widget  |  Widget   |     |NULL (top edge of Form) |
|-------------+---------+-----------+-----+------------------------|
|horizDistance|Thickness|    int    |     |defaultDistance resource|
|-------------+---------+-----------+-----+------------------------|
|    left     |  Edge   |XawEdgeType|     |       XawRubber        |
|-------------+---------+-----------+-----+------------------------|
|  resizable  | Boolean |  Boolean  |     |         FALSE          |
|-------------+---------+-----------+-----+------------------------|
|    right    |  Edge   |XawEdgeType|     |       XawRubber        |
|-------------+---------+-----------+-----+------------------------|
|     top     |  Edge   |XawEdgeType|     |       XawRubber        |
|-------------+---------+-----------+-----+------------------------|
|vertDistance |Thickness|    int    |     |defaultDistance resource|
+------------------------------------------------------------------+

bottom
left
right
top            What to do with this edge of the child when
               the parent is resized.  This resource may be
               any edgeType.  See Layout Semantics for
               details.

fromHoriz
fromVert       Which widget this child should be placed
               underneath (or to the right of).  If a value
               of NULL is specified then this widget will be
               positioned relative to the edge of the par-
               ent.

horizDistance
vertDistance   The amount of space, in pixels, between this
               child and its left or upper neighbor.

resizable      If this resource is False then the parent
               widget will ignore all geometry request made
               by this child.  The parent may still resize
               this child itself, however.

Layout Semantics

The Form widget uses two different sets of layout semantics. One is used when
initially laying out the children. The other is used when the Form is resized.

The first layout method uses the fromVert and fromHoriz resources to place the
children of the Form. A single pass is made through the Form widget's children
in the order that they were created. Each child is then placed in the Form
widget below or to the right of the widget specified by the fromVert and
fromHoriz resources. The distance the new child is placed from its left or
upper neighbor is deter- mined by the horizDistance and vertDistance resources.
This implies some things about how the order of creation affects the possible
placement of the children. The Form widget registers a string to widget
converter which does not post- pone conversion and does not cache conversion
results.

The second layout method is used when the Form is resized. It does not matter
what causes this resize, and it is possi- ble for a resize to happen before the
widget becomes visible (due to constraints imposed by the parent of the Form).
This layout method uses the bottom, top, left, and right resources. These
resources are used to determine what will happen to each edge of the child when
the Form is resized. If a value of XawChain <something> is specified, the the
edge of the child will remain a fixed distance from the chain edge of the Form.
For example if XawChainLeft is specified for the right resource of a child then
the right edge of that child will remain a fixed distance from the left edge of
the Form widget. If a value of XawRubber is specified, that edge will grow by
the same percentage that the Form grew. For instance if the Form grows by 50%
the left edge of the child (if specified as XawRubber will be 50% farther from
the left edge of the Form). One must be very careful when specifying these
resources, for when they are specified incorrectly children may overlap or
completely occlude other children when the Form widget is resized.

+-----------------------------------------------------------------------------+
|  Edge Type   |Resource Name|                  Description                   |
|--------------+-------------+------------------------------------------------|
|XawChainBottom| ChainBottom |  Edge remains a fixed distance from bottom of  |
|              |             |                      Form                      |
|--------------+-------------+------------------------------------------------|
| XawChainLeft |  ChainLeft  |Edge remains a fixed distance from left of Form |
|--------------+-------------+------------------------------------------------|
|XawChainRight | ChainRight  |Edge remains a fixed distance from right of Form|
|--------------+-------------+------------------------------------------------|
| XawChainTop  |  ChainTop   | Edge remains a fixed distance from top of Form |
|--------------+-------------+------------------------------------------------|
|  XawRubber   |   Rubber    |    Edges will move a proportional distance     |
+-----------------------------------------------------------------------------+

Example

If you wish to force the Form to never resize one or more of its children, then
set left and right to XawChainLeft and top and bottom to XawChainTop. This will
cause the child to remain a fixed distance from the top and left edges of the
Form, and never to resize.

Convenience Routines

To force or defer a re-layout of the Form, use

void XawFormDoLayout(Widget w, Boolean do_layout);

w         Specifies the Form widget.

do_layout Specifies whether the layout of the Form widget is enabled (True) or
          disabled (False).

When making several changes to the children of a Form widget after the Form has
been realized, it is a good idea to disable relayout until after all changes
have been made.

Paned Widget




Application Header file <X11/Xaw/Paned.h>

Class Header file       <X11/Xaw/PanedP.h>

Class           panedWidgetClass

Class Name      Paned

Superclass      Constraint


The Paned widget manages children in a vertically or horizontally tiled
fashion. The panes may be dynamically resized by the user by using the grips
that appear near the right or bottom edge of the border between two panes.

The Paned widget may accept any widget class as a pane except Grip. Grip
widgets have a special meaning for the Paned widget, and adding a Grip as its
own pane will confuse the Paned widget.

Using the Paned Widget

The grips allow the panes to be resized by the user. The semantics of how these
panes resize is somewhat complicated, and warrants further explanation here.
When the mouse pointer is positioned on a grip and pressed, an arrow is
displayed that indicates the pane that is to be to be resized. While keeping
the mouse button down, the user can move the grip up and down (or left and
right). This, in turn, changes the size of the pane. The size of the Paned
widget will not change. Instead, it chooses another pane (or panes) to resize.
For more details on which pane it chooses to resize, see Layout Semantics.

One pointer binding allows the border between two panes to be moved, without
affecting any of the other panes. When this occurs the pointer will change to
an arrow that points along the pane border.

The default bindings for the Paned widget's grips are:

+------------------------------------------------------------------+
|Mouse button|Pane to Resize - Vertical|Pane to Resize - Horizontal|
|------------+-------------------------+---------------------------|
|  1 (left)  |     above the grip      |     left of the grip      |
|------------+-------------------------+---------------------------|
| 2 (middle) |      adjust border      |       adjust border       |
|------------+-------------------------+---------------------------|
| 3 (right)  |     below the grip      |     right of the grip     |
|------------+-------------------------+---------------------------|
|     _      |                         |                           |
+------------------------------------------------------------------+

Resources

When creating a Paned widget instance, the following resources are retrieved
from the argument list or the resource database:

+------------------------------------------------------------------------------------+
|         Name          |      Class      |      Type      |Notes|   Default Value   |
|-----------------------+-----------------+----------------+-----+-------------------|
|     accelerators      |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------------+-----------------+----------------+-----+-------------------|
|   ancestorSensitive   |AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------------+-----------------+----------------+-----+-------------------|
|      background       |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------------+-----------------+----------------+-----+-------------------|
|   backgroundPixmap    |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------------+-----------------+----------------+-----+-------------------|
|     betweenCursor     |     Cursor      |     Cursor     |  A  |    Depends on     |
|                       |                 |                |     |    orientation    |
|-----------------------+-----------------+----------------+-----+-------------------|
|      borderColor      |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------------+-----------------+----------------+-----+-------------------|
|     borderPixmap      |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------------+-----------------+----------------+-----+-------------------|
|      borderWidth      |   BorderWidth   |   Dimension    |     |         1         |
|-----------------------+-----------------+----------------+-----+-------------------|
|       children        |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------------+-----------------+----------------+-----+-------------------|
|       colormap        |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------------+-----------------+----------------+-----+-------------------|
|        cursor         |     Cursor      |     Cursor     |     |       None        |
|-----------------------+-----------------+----------------+-----+-------------------|
|         depth         |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------------+-----------------+----------------+-----+-------------------|
|    destroyCallback    |    Callback     | XtCallbackList |     |       NULL        |
|-----------------------+-----------------+----------------+-----+-------------------|
|      gripCursor       |     Cursor      |     Cursor     |  A  |    Depends on     |
|                       |                 |                |     |    orientation    |
|-----------------------+-----------------+----------------+-----+-------------------|
|      gripIndent       |   GripIndent    |    Position    |     |        10         |
|-----------------------+-----------------+----------------+-----+-------------------|
|   gripTranslations    |  Translations   |TranslationTable|     |     see below     |
|-----------------------+-----------------+----------------+-----+-------------------|
|        height         |     Height      |   Dimension    |  A  |    Depends on     |
|                       |                 |                |     |    orientation    |
|-----------------------+-----------------+----------------+-----+-------------------|
|horizontalBetweenCursor|     Cursor      |     Cursor     |     |    sb_up_arrow    |
|-----------------------+-----------------+----------------+-----+-------------------|
| horizontalGripCursor  |     Cursor      |     Cursor     |     | sb_h_double_arrow |
|-----------------------+-----------------+----------------+-----+-------------------|
|  internalBorderColor  |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------------+-----------------+----------------+-----+-------------------|
|  internalBorderWidth  |   BorderWidth   |   Dimension    |     |         1         |
|-----------------------+-----------------+----------------+-----+-------------------|
|      leftCursor       |     Cursor      |     Cursor     |     |   sb_left_arrow   |
|-----------------------+-----------------+----------------+-----+-------------------|
|      lowerCursor      |     Cursor      |     Cursor     |     |   sb_down_arrow   |
|-----------------------+-----------------+----------------+-----+-------------------|
|   mappedWhenManaged   |MappedWhenManaged|    Boolean     |     |       True        |
|-----------------------+-----------------+----------------+-----+-------------------|
|      numChildren      |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------------+-----------------+----------------+-----+-------------------|
|      orientation      |   Orientation   |  Orientation   |     | XtorientVertical  |
|-----------------------+-----------------+----------------+-----+-------------------|
|     refigureMode      |     Boolean     |    Boolean     |     |       True        |
|-----------------------+-----------------+----------------+-----+-------------------|
|      rightCursor      |     Cursor      |     Cursor     |     |  sb_right_arrow   |
|-----------------------+-----------------+----------------+-----+-------------------|
|        screen         |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------------+-----------------+----------------+-----+-------------------|
|       sensitive       |    Sensitive    |    Boolean     |     |       True        |
|-----------------------+-----------------+----------------+-----+-------------------|
|     translations      |  Translations   |TranslationTable|     |       NULL        |
|-----------------------+-----------------+----------------+-----+-------------------|
|      upperCursor      |     Cursor      |     Cursor     |     |    sb_up_arrow    |
|-----------------------+-----------------+----------------+-----+-------------------|
| verticalBetweenCursor |     Cursor      |     Cursor     |     |   sb_left_arrow   |
|-----------------------+-----------------+----------------+-----+-------------------|
|  verticalGripCursor   |     Cursor      |     Cursor     |     | sb_v_double_arrow |
|-----------------------+-----------------+----------------+-----+-------------------|
|         width         |      Width      |   Dimension    |  A  |    Depends on     |
|                       |                 |                |     |    orientation    |
|-----------------------+-----------------+----------------+-----+-------------------|
|           x           |      Paned      |    Position    |     |         0         |
|-----------------------+-----------------+----------------+-----+-------------------|
|           y           |      Paned      |    Position    |     |         0         |
|-----------------------+-----------------+----------------+-----+-------------------|
|           _           |                 |                |     |                   |
+------------------------------------------------------------------------------------+

                        The cursor to use when the mouse pointer is over the
                        Paned widget, but not in any of its children (children
cursor                  may also inherit this cursor). It should be noted that
                        the internal borders are actually part of the Paned
                        widget, not the children.

                        The cursor to use when the grips are not active. The
gripCursor              default value is verticalGripCursor or
                        horizontalGripCursor depending on the orientation of
                        the Paned widget.

gripIndent              The amount of space left between the right (or bottom)
                        edge of the Paned widget and all the grips.

gripTranslation         Translation table that will be applied to all grips.

horizontalBetweenCursor

                        The cursor to be used for the grip when changing the
verticalBetweenCursor   boundary between two panes. These resources allow the
                        cursors to be different depending on the orientation of
                        the Paned widget.

horizontalGripCursor

                        The cursor to be used for the grips when they are not
verticalGripCursor      active. These resources allow the cursors to be
                        different depending on the orientation of the Paned
                        widget.

                        A pixel value which indexes the widget's colormap to
                        derive the internal border color of the widget's
                        window. The class name of this resource allows 
internalBorderColor     Paned*BorderColor: blue to set the internal border
                        color for the Paned widget. An optimization is invoked
                        if internalBorderColor and background are the same, and
                        the internal borders are not drawn. internalBorderWidth
                        is still left between the panes, however.

                        The width of the internal borders. This is the amount
internalBorderWidth     of space left between the panes. The class name of this
                        resource allows Paned*BorderWidth: 3 to set the
                        internal border width for the Paned widget.

leftCursor

                        The cursor used to indicate which is the important pane
rightCursor             to resize when the Paned widget is oriented
                        horizontally.

lowerCursor

                        The cursor used to indicate which is the important pane
                        to resize when the Paned widget is oriented vertically.
upperCursor             This is not the same as the number of panes, since this
                        also contains a grip for some of the panes, use
                        XawPanedGetNumSub to retrieve the number of panes.

orientation             The orientation to stack the panes. This value can be
                        either XtorientVertical or XtorientHorizontal.

                        This resource allows pane layout to be suspended. If
refigureMode            this value is False, then no layout actions will be
                        taken. This may improve efficiency when adding or
                        removing more than one pane from the Paned widget.

Constraint Resources

Each child of the Paned widget may request special layout resources be applied
to it. These constraint resources allow the Paned widget's children to specify
individual layout requirements.

+-------------------------------------------------------------------+
|      Name       |      Class      |  Type   |Notes| Default Value |
|-----------------+-----------------+---------+-----+---------------|
|   allowResize   |     Boolean     | Boolean |     |     False     |
|-----------------+-----------------+---------+-----+---------------|
|       max       |       Max       |Dimension|     |   Infinity    |
|-----------------+-----------------+---------+-----+---------------|
|       min       |       Min       |Dimension|     |Height of Grips|
|-----------------+-----------------+---------+-----+---------------|
|preferredPaneSize|PreferredPaneSize|Dimension|     |   ask child   |
|-----------------+-----------------+---------+-----+---------------|
|resizeToPreferred|     Boolean     | Boolean |     |     False     |
|-----------------+-----------------+---------+-----+---------------|
|    showGrip     |    ShowGrip     | Boolean |     |     True      |
|-----------------+-----------------+---------+-----+---------------|
|   skipAdjust    |     Boolean     | Boolean |     |     False     |
|-----------------+-----------------+---------+-----+---------------|
|        _        |                 |         |     |               |
+-------------------------------------------------------------------+

allowResize       If this value is False the the Paned widget will disallow all
                  geometry requests from this child.

max

                  The absolute maximum or minimum size for this pane. These
min               values will never be overridden by the Paned widget. This may
                  cause some panes to be pushed off the bottom (or right) edge
                  of the paned widget.

                  Normally the paned widget makes a QueryGeometry call on a
                  child to determine the preferred size of the child's pane.
preferredPaneSize There are times when the application programmer or the user
                  has a better idea of the preferred size of a pane. Setting
                  this resource causes the value passed to be interpreted as
                  the preferred size, in pixels, of this pane.

                  Determines whether or not to resize each pane to its
resizeToPreferred preferred size when the Paned widget is resized. See Layout
                  Semantics for details.

                  If True then a grip will be shown for this pane. The grip
showGrip          associated with a pane is either below or to the right of the
                  pane. No grip is ever shown for the last pane.

                  This resource is used to determine which pane is forced to be
skipAdjust        resized. Setting this value to True makes this pane less
                  likely to be forced to be resized. See Layout Semantics for
                  details.

Layout Semantics

In order to make effective use of the Paned widget it is helpful to know the
rules it uses to determine which child will be resized in any given situation.
There are three rules used to determine which child is resized. While these
rules are always the same, the panes that are searched can change depending
upon what caused the relayout.

Layout Rules

1 Do not let a pane grow larger than its max or smaller than its min.

2 Do not adjust panes with skipAdjust set.

3 Do not adjust panes away from their preferred size, although moving one
  closer to its preferred size is fine.

When searching the children the Paned widget looks for panes that satisfy all
the rules, and if unsuccessful then it eliminates rule 3 and then 2. Rule 1 is
always enforced.

If the relayout is due to a resize or change in management then the panes are
searched from bottom to top. If the relayout is due to grip movement then they
are searched from the grip selected in the direction opposite the pane
selected.

Resizing Panes from a Grip Action

The pane above the grip is resized by invoking the GripAction with UpLeftPane
specified. The panes below the grip are each checked against all rules, then
rules 2 and 1 and finally against rule 1 only. No pane above the chosen pane
will ever be resized.

The pane below the grip is resized by invoking the GripAction with LowRightPane
specified. The panes above the grip are each checked in this case. No pane
below the chosen pane will ever be resized.

Invoking GripAction with ThisBorderOnly specified just moves the border between
the panes. No other panes are ever resized.

Resizing Panes after the Paned widget is resized.

When the Pane widget is resized it must determine a new size for each pane.
There are two methods of doing this. The Paned widget can either give each pane
its preferred size and then resize the panes to fit, or it can use the current
sizes and then resize the panes to fit. The resizeToPreferred resource allows
the application to tell the Paned widget whether to query the child about its
preferred size (subject to the the preferredPaneSize) or to use the current
size when refiguring the pane locations after the pane has been resized.

There is one special case. All panes assume they should resize to their
preferred size until the Paned widget becomes visible to the user.

Managing Children and Geometry Management

The Paned widget always resizes its children to their preferred sizes when a
new child is managed, or a geometry management request is honored. The Paned
widget will first attempt to resize itself to contain its panes exactly. If
this is not possible then it will hunt through the children, from bottom to top
(right to left), for a pane to resize.

Special Considerations

When a user resizes a pane with the grips, the Paned widget assumes that this
new size is the preferred size of the pane.

Grip Translations

The Paned widget has no action routines of its own, as all actions are handled
through the grips. The grips are each assigned a default Translation table.



        <Btn1Down>:     GripAction(Start, UpLeftPane)

        <Btn2Down>:     GripAction(Start, ThisBorderOnly)
        <Btn3Down>:     GripAction(Start, LowRightPane)
        <Btn1Motion>:   GripAction(Move, UpLeftPane)
        <Btn2Motion>:   GripAction(Move, ThisBorderOnly)
        <Btn3Motion>:   GripAction(Move, LowRightPane)
        Any<BtnUp>:     GripAction(Commit)

The Paned widget interprets the GripAction as taking two arguments. The first
argument may be any of the following:

       Sets up the Paned widget for resizing and changes the cursor of the
Start  grip. The second argument determines which pane will be resized, and can
       take on any of the three values shown above.

       The internal borders are drawn over the current pane locations to
       animate where the borders would actually be placed if you were to move
Move   this border as shown. The second argument must match the second argument
       that was passed to the Start action, that began this process. If these
       arguments are not passed, the behavior is undefined.

       This argument causes the Paned widget to commit the changes selected by
Commit the previously started action. The cursor is changed back to the grip's
       inactive cursor. No second argument is needed in this case.

Convenience Routines

To enable or disable a child's request for pane resizing, use
XawPanedAllowResize :

void XawPanedAllowResize(Widget w, Boolean allow_resize);

w            Specifies the child pane.

allow_resize Specifies whether or not resizing requests for this child will be
             granted by the Paned widget.

If allow_resize is True, the Paned widget allows geometry requests from the
child to change the pane's height. If allow_resize is False, the Paned widget
ignores geometry requests from the child to change the pane's height. The
default state is True before the Pane is realized and False after it is
realized. This procedure is equivalent to changing the allowResize constraint
resource for the child.

To change the minimum and maximum height settings for a pane, use
XawPanedSetMinMax :

void XawPanedSetMinMax(Widget w, intmin, max);

w   Specifies the child pane.

min Specifies the new minimum height of the child, expressed in pixels.

max Specifies new maximum height of the child, expressed in pixels.

This procedure is equivalent to setting the min and max constraint resources
for the child.

To retrieve the minimum and maximum height settings for a pane, use
XawPanedGetMinMax :

void XawPanedGetMinMax(Widget w, int*min_return, *max_return);

w          Specifies the child pane.

min_return Returns the minimum height of the child, expressed in pixels.

max_return Returns the maximum height of the child, expressed in pixels.

This procedure is equivalent to getting the min and max resources for this
child child.

To enable or disable automatic recalculation of pane sizes and positions, use
XawPanedSetRefigureMode :

void XawPanedSetRefigureMode(Widget w, Boolean mode);

w    Specifies the Paned widget.

mode Specifies whether the layout of the Paned widget is enabled (True) or
     disabled (False).

When making several changes to the children of a Paned widget after the Paned
has been realized, it is a good idea to disable relayout until after all
changes have been made.

To retrieve the number of panes in a paned widget use XawPanedGetNumSub:

int XawPanedGetNumSub(Widget w);

w Specifies the Paned widget.

This function returns the number of panes in the Paned widget. This is not the
same as the number of children, since the grips are also children of the Paned
widget.

Porthole Widget




Application Header file <X11/Xaw/Porthole.h>

Class Header file       <X11/Xaw/PortholeP.h>

Class           portholeWidgetClass

Class Name      Porthole

Superclass      Composite


The Porthole widget provides geometry management of a list of arbitrary
widgets, only one of which may be managed at any particular time. The managed
child widget is reparented within the porthole and is moved around by the
application (typically under the control of a Panner widget).

Resources

When creating a Porthole widget instance, the following resources are retrieved
from the argument list or from the resource database:

+------------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |Notes|   Default Value   |
|-----------------+-----------------+----------------+-----+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   background    |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------+-----------------+----------------+-----+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |     |         1         |
|-----------------+-----------------+----------------+-----+-------------------|
|    children     |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    colormap     |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------+-----------------+----------------+-----+-------------------|
|      depth      |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------+-----------------+----------------+-----+-------------------|
| destroyCallback |    Callback     | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|     height      |     Height      |   Dimension    |  A  |    see Layout     |
|                 |                 |                |     |     Semantics     |
|-----------------+-----------------+----------------+-----+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   numChildren   |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
| reportCallback  | ReportCallback  |    Callback    |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|     screen      |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------+-----------------+----------------+-----+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|  translations   |  Translations   |TranslationTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|      width      |      Width      |   Dimension    |  A  |    see Layout     |
|                 |                 |                |     |     Semantics     |
|-----------------+-----------------+----------------+-----+-------------------|
|        x        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        y        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        _        |                 |                |     |                   |
+------------------------------------------------------------------------------+

reportCallback A list of functions to invoke whenever the managed child widget
               changes size or position.

Layout Semantics

The Porthole widget allows its managed child to request any size that is as
large or larger than the Porthole itself and any location so long as the child
still obscures all of the Porthole. This widget typically is used with a Panner
widget.

Porthole Callbacks

The functions registered on the reportCallback list are invoked whenever the
managed child changes size or position:

void ReportProc(Widget porthole, XtPointer client_data, XtPointer report);

porthole    Specifies the Porthole widget.

client_data Specifies the client data.

report      Specifies a pointer to an XawPannerReport structure containing the
            location and size of the slider and the size of the canvas.

Tree Widget

Application Header file <X11/Xaw/Tree.h>
Class Header file       <X11/Xaw/TreeP.h>
Class           treeWidgetClass
Class Name      Tree
Superclass      Constraint

The Tree widget provides geometry management of arbitrary widgets arranged in a
directed, acyclic graph (i.e., a tree). The hierarchy is constructed by
attaching a constraint resource called treeParent to each widget indicating
which other node in the tree should be treated as the widget's superior. The
structure of the tree is shown by laying out the nodes in the standard format
for tree diagrams with lines drawn connecting each node with its children.

The Tree sizes itself according to the needs of its children and is not
intended to be resized by its parent. Instead, it should be placed inside
another composite widget (such as the Porthole or Viewport) that can be used to
scroll around in the tree.

Resources

When creating a Tree widget instance, the following resources are retrieved
from the argument list or from the resource database:

+------------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |Notes|   Default Value   |
|-----------------+-----------------+----------------+-----+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
| autoReconfigure | AutoReconfigure |    Boolean     |     |       False       |
|-----------------+-----------------+----------------+-----+-------------------|
|   background    |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------+-----------------+----------------+-----+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |     |         1         |
|-----------------+-----------------+----------------+-----+-------------------|
|    children     |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    colormap     |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------+-----------------+----------------+-----+-------------------|
|      depth      |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------+-----------------+----------------+-----+-------------------|
| destroyCallback |    Callback     | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|   foreground    |   Foreground    |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|     gravity     |     Gravity     |   XtGravity    |     |    WestGravity    |
|-----------------+-----------------+----------------+-----+-------------------|
|     height      |     Height      |   Dimension    |  A  |    see Layout     |
|                 |                 |                |     |     Semantics     |
|-----------------+-----------------+----------------+-----+-------------------|
|     hSpace      |     HSpace      |   Dimension    |     |         4         |
|-----------------+-----------------+----------------+-----+-------------------|
|    lineWidth    |    LineWidth    |   Dimension    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   numChildren   |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|     screen      |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------+-----------------+----------------+-----+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|     vSpace      |     VSpace      |   Dimension    |     |         4         |
|-----------------+-----------------+----------------+-----+-------------------|
|  translations   |  Translations   |TranslationTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|      width      |      Width      |   Dimension    |  A  |    see Layout     |
|                 |                 |                |     |     Semantics     |
|-----------------+-----------------+----------------+-----+-------------------|
|        x        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        y        |    Position     |    Position    |     |         0         |
+------------------------------------------------------------------------------+

autoReconfigure Whether or not to layout the tree every time a node is added or
                removed.

                Specifies the side of the widget from which the tree should
gravity         grow. Valid values include WestGravity, NorthGravity,
                EastGravity, and SouthGravity.

hSpace

                The amount of space, in pixels, to leave between the children.
vSpace          This resource specifies the amount of space left between the
                outermost children and the edge of the box.

lineWidth       The width of the lines from nodes that do not have a treeGC
                constraint resource to their children.

Constraint Resources

Each child of the Tree widget must specify its superior node in the tree. In
addition, it may specify a GC to use when drawing a line between it and its
inferior nodes.

+------------------------------------------------+
|   Name   |  Class   | Type |Notes|Default Value|
|----------+----------+------+-----+-------------|
|  treeGC  |  TreeGC  |  GC  |     |    NULL     |
|----------+----------+------+-----+-------------|
|treeParent|TreeParent|Widget|     |    NULL     |
+------------------------------------------------+

           This specifies the GC to use when drawing lines between this widget
treeGC     and its inferiors in the tree. If this resource is not specified,
           the Tree's foreground and lineWidth will be used.

           This specifies the superior node in the tree for this widget. The
treeParent default is for the node to have no superior (and to therefore be at
           the top of the tree).

Layout Semantics

Each time a child is managed or unmanaged, the Tree widget will attempt to
reposition the remaining children to fix the shape of the tree if the resource
is set. Children at the top (most superior) of the tree are drawn at the side
specified by the resource.

After positioning all children, the Tree widget attempts to shrink its own size
to the minimum dimensions required for the layout.

Convenience Routines

The most efficient way to layout a tree is to set autoReconfigure to False and
then use the XawTreeForceLayout routine to arrange the children.

void XawTreeForceLayout(Widget w);

w Specifies the Tree widget.

Viewport Widget




Application Header file <X11/Xaw/Viewport.h>

Class Header file       <X11/Xaw/ViewportP.h>

Class           viewportWidgetClass

Class Name      Viewport

Superclass      Form


The Viewport widget consists of a frame window, one or two Scrollbars, and an
inner window. The size of the frame window is determined by the viewing size of
the data that is to be displayed and the dimensions to which the Viewport is
created. The inner window is the full size of the data that is to be displayed
and is clipped by the frame window. The Viewport widget controls the scrolling
of the data directly. No application callbacks are required for scrolling.

When the geometry of the frame window is equal in size to the inner window, or
when the data does not require scrolling, the Viewport widget automatically
removes any scrollbars. The forceBars option causes the Viewport widget to
display all scrollbars permanently.

Resources

When creating a Viewport widget instance, the following resources are retrieved
from the argument list or the resource database:

+------------------------------------------------------------------------------+
|      Name       |      Class      |      Type      |Notes|   Default Value   |
|-----------------+-----------------+----------------+-----+-------------------|
|  accelerators   |  Accelerators   |AcceleratorTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|   allowHoriz    |     Boolean     |    Boolean     |     |       False       |
|-----------------+-----------------+----------------+-----+-------------------|
|    allowVert    |     Boolean     |    Boolean     |     |       False       |
|-----------------+-----------------+----------------+-----+-------------------|
|ancestorSensitive|AncestorSensitive|    Boolean     |  D  |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   background    |   Background    |     Pixel      |     |XtDefaultBackground|
|-----------------+-----------------+----------------+-----+-------------------|
|backgroundPixmap |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderColor   |   BorderColor   |     Pixel      |     |XtDefaultForeground|
|-----------------+-----------------+----------------+-----+-------------------|
|  borderPixmap   |     Pixmap      |     Pixmap     |     |XtUnspecifiedPixmap|
|-----------------+-----------------+----------------+-----+-------------------|
|   borderWidth   |   BorderWidth   |   Dimension    |     |         1         |
|-----------------+-----------------+----------------+-----+-------------------|
|    children     |    ReadOnly     |   WidgetList   |  R  |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    colormap     |    Colormap     |    Colormap    |     | Parent's Colormap |
|-----------------+-----------------+----------------+-----+-------------------|
|      depth      |      Depth      |      int       |  C  |  Parent's Depth   |
|-----------------+-----------------+----------------+-----+-------------------|
| destroyCallback |    Callback     | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    forceBars    |     Boolean     |    Boolean     |     |       False       |
|-----------------+-----------------+----------------+-----+-------------------|
|     height      |     Height      |   Dimension    |     |height of the child|
|-----------------+-----------------+----------------+-----+-------------------|
|mappedWhenManaged|MappedWhenManaged|    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|   numChildren   |    ReadOnly     |    Cardinal    |  R  |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
| reportCallback  | ReportCallback  | XtCallbackList |     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|     screen      |     Screen      |     Screen     |  R  |  Parent's Screen  |
|-----------------+-----------------+----------------+-----+-------------------|
|    sensitive    |    Sensitive    |    Boolean     |     |       True        |
|-----------------+-----------------+----------------+-----+-------------------|
|  translations   |  Translations   |TranslationTable|     |       NULL        |
|-----------------+-----------------+----------------+-----+-------------------|
|    useBottom    |     Boolean     |    Boolean     |     |       False       |
|-----------------+-----------------+----------------+-----+-------------------|
|    useRight     |     Boolean     |    Boolean     |     |       False       |
|-----------------+-----------------+----------------+-----+-------------------|
|      width      |      Width      |   Dimension    |     |width of the child |
|-----------------+-----------------+----------------+-----+-------------------|
|        x        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        y        |    Position     |    Position    |     |         0         |
|-----------------+-----------------+----------------+-----+-------------------|
|        _        |                 |                |     |                   |
+------------------------------------------------------------------------------+

allowHoriz

               If these resources are False then the Viewport will never create
allowVert      a scrollbar in this direction. If it is True then the scrollbar
               will only appear when it is needed, unless forceBars is True.

               When True the scrollbars that have been allowed will always be
forceBars      visible on the screen. If False the scrollbars will be visible
               only when the inner window is larger than the frame.

               These callbacks will be executed whenever the Viewport adjusts
reportCallback the viewed area of the child. The call_data parameter is a
               pointer to an XawPannerReport structure.

useBottom

               By default the scrollbars appear on the left and top of the
useRight       screen. These resources allow the vertical scrollbar to be
               placed on the right edge of the Viewport, and the horizontal
               scrollbar on the bottom edge of the Viewport.

Layout Semantics

The Viewport widget manages a single child widget. When the size of the child
is larger than the size of the Viewport, the user can interactively move the
child within the Viewport by repositioning the scrollbars.

The default size of the Viewport before it is realized is the width and/or
height of the child. After it is realized, the Viewport will allow its child to
grow vertically or horizontally if allowVert or allowHoriz are set,
respectively. If the corresponding vertical or horizontal scrollbar is not
enabled, the Viewport will propagate the geometry request to its own parent and
the child will be allowed to change size only if the Viewport's parent allows
it. Regardless of whether or not scrollbars are enabled in the corresponding
direction, if the child requests a new size smaller than the Viewport size, the
change will be allowed only if the parent of the Viewport allows the Viewport
to shrink to the appropriate dimension.

The scrollbar children of the Viewport are named horizontal and vertical. By
using these names the programmer can specify resources for the individual
scrollbars. XtSetValues can be used to modify the resources dynamically once
the widget ID has been obtained with XtNameToWidget.

Note

Although the Viewport is a Subclass of the Form, no resources for the Form may
be supplied for any of the children of the Viewport. These constraints are
managed internally and are not meant for public consumption.

Chapter 7. Creating New Widgets (Subclassing)

Table of Contents

Public Header File
Private Header File
Widget Source File

Although the task of creating a new widget may at first appear a little
daunting, there is a basic simple pattern that all widgets follow. The Athena
Widget library contains a special widget called the Template widget that is
intended to assist the novice widget programmer in writing a custom widget.

Reasons for wishing to write a custom widget include:

  * Providing a graphical interface not currently supported by any existing
    widget set.

  * Convenient access to resource management procedures to obtain fonts,
    colors, etc., even if user customization is not desired.

  * Convenient access to user input dispatch and translation management
    procedures.

  * Access to callback mechanism for building higher-level application
    libraries.

  * Customizing the interface or behavior of an existing widget to suit a
    special application need.

  * Desire to allow user customization of resources such as fonts, colors,
    etc., or to allow convenient re-binding of keys and buttons to internal
    functions.

  * Converting a non-Toolkit application to use the Toolkit.

In each of these cases, the operation needed to create a new widget is to
"subclass" an existing one. If the desired semantics of the new widget are
similar to an existing one, then the implementation of the existing widget
should be examined to see how much work would be required to create a subclass
that will then be able to share the existing class methods. Much time will be
saved in writing the new widget if an existing widget class Expose, Resize and/
or GeometryManager method can be used by the subclass.

Note that some trivial uses of a ``bare-bones'' widget may be achieved by
simply creating an instance of the Core widget. The class variable to use when
creating a Core widget is widgetClass. The geometry of the Core widget is
determined entirely by the parent widget.

It is very often the case than an application will have a special need for a
certain set of functions and that many copies of these functions will be
needed. For example, when converting an older application to use the Toolkit,
it may be desirable to have a "Window Widget" class that might have the
following semantics:

  * Allocate 2 drawing colors in addition to a background color.

  * Allocate a text font.

  * Execute an application-supplied function to handle exposure events.

  * Execute an application-supplied function to handle user input events.

It is obvious that a completely general-purpose WindowWidgetClass could be
constructed that would export all class methods as callbacks lists, but such a
widget would be very large and would have to choose some arbitrary number of
resources such as colors to allocate. An application that used many instances
of the general-purpose widget would therefore un-necessarily waste many
resources.

In this section, an outline will be given of the procedure to follow to
construct a special-purpose widget to address the items listed above. The
reader should refer to the appropriate sections of the X Toolkit Intrinsics - C
Language Interface for complete details of the material outlined here. Section
1.4 of the Intrinsics should be read in conjunction with this section.

All Athena widgets have three separate files associated with them:

  * A "public" header file containing declarations needed by applications
    programmers

  * A "private" header file containing additional declarations needed by the
    widget and any subclasses

  * A source code file containing the implementation of the widget

This separation of functions into three files is suggested for all widgets, but
nothing in the Toolkit actually requires this format. In particular, a private
widget created for a single application may easily combine the "public" and
"private" header files into a single file, or merge the contents into another
application header file. Similarly, the widget implementation can be merged
into other application code.

In the following example, the public header file < X11/Xaw/Template.h >, the
private header file < X11/Xaw/TemplateP.h > and the source code file < X11/Xaw/
Template.c > will be modified to produce the "WindowWidget" described above. In
each case, the files have been designed so that a global string replacement of
"Template" and "template" with the name of your new widget, using the
appropriate case, can be done.

Public Header File

The public header file contains declarations that will be required by any
application module that needs to refer to the widget; whether to create an
instance of the class, to perform an XtSetValues operation, or to call a public
routine implemented by the widget class.

The contents of the Template public header file, < X11/Xaw/Template.h >, are:

..


/* Copyright (c) X Consortium 1987, 1988 */

#ifndef _Template_h
#define _Template_h

/****************************************************************
 *
 * Template widget
 *
 ****************************************************************/

/* Resources:

 Name   Class           RepType Default Value
 ----           -----           ------- -------------
 background     Background              Pixel   XtDefaultBackground
 border BorderColor             Pixel   XtDefaultForeground
 borderWidth    BorderWidth             Dimension       1
 destroyCallback        Callback                Pointer NULL
 height Height          Dimension       0
 mappedWhenManaged      MappedWhenManaged       Boolean True
 sensitive      Sensitive               Boolean True
 width  Width           Dimension       0
 x              Position                Position        0
 y              Position                Position        0

*/

/* define any special resource names here that are not in <X11/StringDefs.h> */

#define XtNtemplateResource "templateResource"

#define XtCTemplateResource "TemplateResource"

/* declare specific TemplateWidget class and instance datatypes */

typedef struct _TemplateClassRec*       TemplateWidgetClass;
typedef struct _TemplateRec*    TemplateWidget;

/* declare the class constant */

extern WidgetClass templateWidgetClass;

#endif /* _Template_h */


You will notice that most of this file is documentation. The crucial parts are
the last 8 lines where macros for any private resource names and classes are
defined and where the widget class datatypes and class record pointer are
declared.

For the "WindowWidget", we want 2 drawing colors, a callback list for user
input and an exposeCallback callback list, and we will declare three
convenience procedures, so we need to add




/* Resources:
        ...
 callback       Callback        Callback        NULL
 drawingColor1  Color   Pixel           XtDefaultForeground
 drawingColor2  Color   Pixel           XtDefaultForeground
 exposeCallback Callback        Callback        NULL
 font           Font    XFontStruct*    XtDefaultFont
        ...
 */

#define XtNdrawingColor1 "drawingColor1"
#define XtNdrawingColor2 "drawingColor2"
#define XtNexposeCallback "exposeCallback"

extern Pixel WindowColor1(\|/* Widget */\|);
extern Pixel WindowColor2(\|/* Widget */\|);
extern Font\ \ WindowFont(\|/* Widget */\|);


Note that we have chosen to call the input callback list by the generic name,
callback, rather than a specific name. If widgets that define a single
user-input action all choose the same resource name then there is greater
possibility for an application to switch between widgets of different types.

Private Header File

The private header file contains the complete declaration of the class and
instance structures for the widget and any additional private data that will be
required by anticipated subclasses of the widget. Information in the private
header file is normally hidden from the application and is designed to be
accessed only through other public procedures; e.g. XtSetValues .

The contents of the Template private header file, < X11/Xaw/TemplateP.h >, are:

/* Copyright (c) X Consortium 1987, 1988
 */

#ifndef _TemplateP_h
#define _TemplateP_h

#include <X11/Xaw/Template.h>
/* include superclass private header file */
#include <X11/CoreP.h>

/* define unique representation types not found in <X11/StringDefs.h> */

#define XtRTemplateResource "TemplateResource"

typedef struct {
        int empty;
} TemplateClassPart;

typedef struct _TemplateClassRec {
        CoreClassPart   core_class;
        TemplateClassPart       template_class;
} TemplateClassRec;

extern TemplateClassRec templateClassRec;

typedef struct {
        /* resources */
        char* resource;
        /* private state */
} TemplatePart;

typedef struct _TemplateRec {
        CorePart        core;
        TemplatePart    template;
} TemplateRec;

#endif /* _TemplateP_h */


The private header file includes the private header file of its superclass,
thereby exposing the entire internal structure of the widget. It may not always
be advantageous to do this; your own project development style will dictate the
appropriate level of detail to expose in each module.

The "WindowWidget" needs to declare two fields in its instance structure to
hold the drawing colors, a resource field for the font and a field for the
expose and user input callback lists:

typedef struct {
        /* resources */
        Pixel color_1;
        Pixel color_2;
        XFontStruct* font;
        XtCallbackList expose_callback;
        XtCallbackList input_callback;
        /* private state */
        /* (none) */
} WindowPart;

Widget Source File

The source code file implements the widget class itself. The unique part of
this file is the declaration and initialization of the widget class record
structure and the declaration of all resources and action routines added by the
widget class.

The contents of the Template implementation file, < X11/Xaw/Template.c >, are:

/* Copyright (c) X Consortium 1987, 1988
 */

#include <X11/IntrinsicP.h>
#include <X11/StringDefs.h>
#include "TemplateP.h"

static XtResource resources[] = {
#define offset(field) XtOffsetOf(TemplateRec, template.field)
        /* {name, class, type, size, offset, default_type, default_addr}, */
    { XtNtemplateResource, XtCTemplateResource, XtRTemplateResource,
          sizeof(char*), offset(resource), XtRString, (XtPointer) "default" },
#undef offset
};

static void TemplateAction(/* Widget, XEvent*, String*, Cardinal* */);

static XtActionsRec actions[] =
{
        /* {name,       procedure}, */
        {"template",    TemplateAction},
};

static char translations[] =
"       <Key>:  template(\|) \\n\\
";

TemplateClassRec templateClassRec = {
  { /* core fields */
        /* superclass   */      (WidgetClass) &widgetClassRec,
        /* class_name   */      "Template",
        /* widget_size  */      sizeof(TemplateRec),
        /* class_initialize     */      NULL,
        /* class_part_initialize        */      NULL,
        /* class_inited */      FALSE,
        /* initialize   */      NULL,
        /* initialize_hook      */      NULL,
        /* realize      */      XtInheritRealize,
        /* actions      */      actions,
        /* num_actions  */      XtNumber(actions),
        /* resources    */      resources,
        /* num_resources        */      XtNumber(resources),
        /* xrm_class    */      NULLQUARK,
        /* compress_motion      */      TRUE,
        /* compress_exposure    */      TRUE,
        /* compress_enterleave */       TRUE,
        /* visible_interest     */      FALSE,
        /* destroy      */      NULL,
        /* resize       */      NULL,
        /* expose       */      NULL,
        /* set_values   */      NULL,
        /* set_values_hook      */      NULL,
        /* set_values_almost    */      XtInheritSetValuesAlmost,
        /* get_values_hook      */      NULL,
        /* accept_focus */      NULL,
        /* version      */      XtVersion,
        /* callback_private     */      NULL,
        /* tm_table     */      translations,
        /* query_geometry       */      XtInheritQueryGeometry,
        /* display_accelerator  */      XtInheritDisplayAccelerator,
        /* extension    */      NULL
  },
  { /* template fields */
        /* empty        */      0
  }
};

WidgetClass templateWidgetClass = (WidgetClass)&templateClassRec;

The resource list for the "WindowWidget" might look like the following:

static XtResource resources[] = {
#define offset(field) XtOffsetOf(WindowWidgetRec, window.field)
        /* {name, class, type, size, offset, default_type, default_addr}, */
        { XtNdrawingColor1, XtCColor, XtRPixel, sizeof(Pixel),
                  offset(color_1), XtRString, XtDefaultForeground },
        { XtNdrawingColor2, XtCColor, XtRPixel, sizeof(Pixel),
                  offset(color_2), XtRString, XtDefaultForeground },
        { XtNfont, XtCFont, XtRFontStruct, sizeof(XFontStruct*),
                  offset(font), XtRString, XtDefaultFont },
        { XtNexposeCallback, XtCCallback, XtRCallback, sizeof(XtCallbackList),
                  offset(expose_callback), XtRCallback, NULL },
        { XtNcallback, XtCCallback, XtRCallback, sizeof(XtCallbackList),
                  offset(input_callback), XtRCallback, NULL },
#undef offset
};

The user input callback will be implemented by an action procedure which passes
the event pointer as call_data. The action procedure is declared as:

/* ARGSUSED */
static void InputAction(w, event, params, num_params)
        Widget w;
        XEvent *event;
        String *params;         /* unused */
        Cardinal *num_params;   /* unused */
{
        XtCallCallbacks(w, XtNcallback, (XtPointer)event);
}

static XtActionsRec actions[] =
{
        /* {name,       procedure}, */
        {"input",       InputAction},
};

and the default input binding will be to execute the input callbacks on
KeyPress and ButtonPress :

static char translations[] =
"       <Key>:  input(\|) \\n\\
        <BtnDown>:      input(\|) \\
";

In the class record declaration and initialization, the only field that is
different from the Template is the expose procedure:

/* ARGSUSED */
static void Redisplay(w, event, region)
        Widget w;
        XEvent *event;  /* unused */
        Region region;
{
        XtCallCallbacks(w, XtNexposeCallback, (XtPointer)region);
}

WindowClassRec windowClassRec = {

        ...

        /* expose       */      Redisplay,

The "WindowWidget" will also declare three public procedures to return the
drawing colors and the font id, saving the application the effort of
constructing an argument list for a call to XtGetValues :

Pixel WindowColor1(w)
        Widget w;
{
        return ((WindowWidget)w)->window.color_1;
}

Pixel WindowColor2(w)
        Widget w;
{
        return ((WindowWidget)w)->window.color_2;
}

Font WindowFont(w)
        Widget w;
{
        return ((WindowWidget)w)->window.font->fid;
}

The "WindowWidget" is now complete. The application can retrieve the two
drawing colors from the widget instance by calling either XtGetValues , or the
WindowColor functions. The actual window created for the "WindowWidget" is
available by calling the XtWindow function.

Chapter 8. Acknowledgments

Many thanks go to Ralph Swick (Project Athena / Digital) who has contributed
much time and effort to this widget set. Previous versions of the widget set
are largely due to his time and effort. Many of the improvements that I have
been able to make are because he provided a solid foundation to build upon.
While much of the effort has been Ralph's, many other people have contributed
to the code.

Mark Ackerman (formerly Project Athena)
Donna Converse (MIT X Consortium)
Jim Fulton (formerly MIT X Consortium)
Loretta Guarino-Reid (Digital WSL)
Charles Haynes (Digital WSL)
Rich Hyde (Digital WSL)
Mary Larson (Digital UEG)
Joel McCormack (Digital WSL)
Ron Newman (formerly Project Athena)
Jeanne Rich (Digital WSL)
Terry Weissman (formerly Digital WSL)

While not much remains of the X10 toolkit, many of the ideas for this widget
set come from that original version. The design and implementation of the X10
toolkit were done by:

Mike Gancarz (formerly Digital UEG)
Charles Haynes (Digital WSL)
Phil Karlton (formerly Digital WSL)
Kathleen Langone (Digital UEG)
Mary Larson (Digital UEG)
Ram Rao (Digital UEG)
Smokey Wallace (formerly Digital WSL)
Terry Weissman (formerly Digital WSL)

I have used the formatting ideas, and some of the words from previous versions
of this document. The X11R3 Athena widget document was written by:

Ralph R. Swick (Project Athena/ Digital)
Terry Weissman (formerly Digital WSL)
Al Mento (Digital UEG)

Putting this manual together was a major task in and of itself. I would like to
thank Ralph Swick, Donna Converse, and Jim Fulton for taking the time to help
convert my technical knowledge into legible text. A special thanks to Jean Diaz
(O'Reilly and Associates) for spending nearly a month with me working out all
the annoying little details.

Chris D. Peterson
MIT X Consortium 1989

The R5 edition of this document has been edited by the research staff of the
MIT X Consortium, with significant contributions by Jim Fulton (NCD).

Donna Converse
MIT X Consortium 1991

The R6 edition of this document has been edited to reflect changes brought
about by research staff of the Omron Corporation, with special recognition to
Li Yuhong, Seiji Kuwari, and Hiroshi Kuribayashi for the X11R5/contrib/lib/Xaw
internationalization that inspired this version.

Frank Sheeran
Omron Corporation 1994

