libxaw-doc 2:1.0.12-1 / usr / share / doc / libxaw7-dev / Dialog.xml

<sect1 id="Dialog_Widget">
<title>Dialog Widget</title>
<para>
<!-- .LP -->
<!-- .XS -->
<!-- 	Dialog Widget -->
<!-- .XE -->
<!-- .IN "Dialog widget" "" "@DEF@" -->
<literallayout class="monospaced">
<!-- .TA 2.0i -->
<!-- .ta 2.0i -->
<!-- .sp -->
Application Header file	&lt;X11/Xaw/Dialog.h&gt;
<!-- .IN "Dialog.h" "" -->
Class Header file	&lt;X11/Xaw/DialogP.h&gt;
<!-- .IN "DialogP.h" "" -->
Class		dialogWidgetClass
<!-- .IN "dialogWidgetClass" "" -->
Class Name	Dialog
<!-- .IN "Dialog widget" "class name" -->
Superclass	Form
<!-- .sp -->
</literallayout>
</para>
<para>
<!-- .LP -->
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.
</para>
<para>
<!-- .LP -->
The typical Dialog widget contains three areas.  The first line
contains a description of the function of the Dialog widget, for
example, the string <emphasis remap='I'>Filename:</emphasis>.  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.
</para>
<sect2 id='Dialog::Resources'>
<title>Resources</title>
<para>
<!-- .LP -->
When creating a Dialog widget instance, the following resources are
retrieved from the argument list or the resource database:
<!-- .IN "Dialog widget" "resources" -->
<informaltable>
  <tgroup cols='5' align='center'>
  <colspec colname='c1'/>
  <colspec colname='c2'/>
  <colspec colname='c3'/>
  <colspec colname='c4'/>
  <colspec colname='c5'/>
  <thead>
    <row>
      <entry>Name</entry>
      <entry>Class</entry>
      <entry>Type</entry>
      <entry>Notes</entry>
      <entry>Default Value</entry>
    </row>
  </thead>
  <tbody>
    <row>
      <entry>accelerators</entry>
      <entry>Accelerators</entry>
      <entry>AcceleratorTable</entry>
      <entry></entry>
      <entry>NULL</entry>
    </row>
    <row>
      <entry>ancestorSensitive</entry>
      <entry>AncestorSensitive</entry>
      <entry>Boolean</entry>
      <entry>D</entry>
      <entry>True</entry>
    </row>
    <row>
      <entry>background</entry>
      <entry>Background</entry>
      <entry>Pixel</entry>
      <entry></entry>
      <entry>XtDefaultBackground</entry>
    </row>
    <row>
      <entry>backgroundPixmap</entry>
      <entry>Pixmap</entry>
      <entry>Pixmap</entry>
      <entry></entry>
      <entry>XtUnspecifiedPixmap</entry>
    </row>
    <row>
      <entry>borderColor</entry>
      <entry>BorderColor</entry>
      <entry>Pixel</entry>
      <entry></entry>
      <entry>XtDefaultForeground</entry>
    </row>
    <row>
      <entry>borderPixmap</entry>
      <entry>Pixmap</entry>
      <entry>Pixmap</entry>
      <entry></entry>
      <entry>XtUnspecifiedPixmap</entry>
    </row>
    <row>
      <entry>borderWidth</entry>
      <entry>BorderWidth</entry>
      <entry>Dimension</entry>
      <entry></entry>
      <entry>1</entry>
    </row>
    <row>
      <entry>children</entry>
      <entry>ReadOnly</entry>
      <entry>WidgetList</entry>
      <entry>R</entry>
      <entry>NULL</entry>
    </row>
    <row>
      <entry>colormap</entry>
      <entry>Colormap</entry>
      <entry>Colormap</entry>
      <entry></entry>
      <entry>Parent's Colormap</entry>
    </row>
    <row>
      <entry>defaultDistance</entry>
      <entry>Thickness</entry>
      <entry>int</entry>
      <entry></entry>
      <entry>4</entry>
    </row>
    <row>
      <entry>depth</entry>
      <entry>Depth</entry>
      <entry>int</entry>
      <entry>C</entry>
      <entry>Parent's Depth</entry>
    </row>
    <row>
      <entry>destroyCallback</entry>
      <entry>Callback</entry>
      <entry>XtCallbackList</entry>
      <entry></entry>
      <entry>NULL</entry>
    </row>
    <row>
      <entry>height</entry>
      <entry>Height</entry>
      <entry>Dimension</entry>
      <entry>A</entry>
      <entry>Enough space to contain all children</entry>
    </row>
    <row>
      <entry>icon</entry>
      <entry>Icon</entry>
      <entry>Bitmap</entry>
      <entry></entry>
      <entry>None</entry>
    </row>
    <row>
      <entry>label</entry>
      <entry>Label</entry>
      <entry>String</entry>
      <entry></entry>
      <entry>"label"</entry>
    </row>
    <row>
      <entry>mappedWhenManaged</entry>
      <entry>MappedWhenManaged</entry>
      <entry>Boolean</entry>
      <entry></entry>
      <entry>True</entry>
    </row>
    <row>
      <entry>numChildren</entry>
      <entry>ReadOnly</entry>
      <entry>Cardinal</entry>
      <entry>R</entry>
      <entry>0</entry>
    </row>
    <row>
      <entry>screen</entry>
      <entry>Screen</entry>
      <entry>Screen</entry>
      <entry>R</entry>
      <entry>Parent's Screen</entry>
    </row>
    <row>
      <entry>sensitive</entry>
      <entry>Sensitive</entry>
      <entry>Boolean</entry>
      <entry></entry>
      <entry>True</entry>
    </row>
    <row>
      <entry>translations</entry>
      <entry>Translations</entry>
      <entry>TranslationTable</entry>
      <entry></entry>
      <entry>NULL</entry>
    </row>
    <row>
      <entry>value</entry>
      <entry>Value</entry>
      <entry>String</entry>
      <entry></entry>
      <entry>no value widget</entry>
    </row>
    <row>
      <entry>width</entry>
      <entry>Width</entry>
      <entry>Dimension</entry>
      <entry>A</entry>
      <entry>Enough space to contain all children</entry>
    </row>
    <row>
      <entry>x</entry>
      <entry>Position</entry>
      <entry>Position</entry>
      <entry></entry>
      <entry>0</entry>
    </row>
    <row>
      <entry>y</entry>
      <entry>Position</entry>
      <entry>Position</entry>
      <entry></entry>
      <entry>0</entry>
    </row>
    <row>
      <entry>_</entry>
    </row>
  </tbody>
  </tgroup>
</informaltable>
<!-- .Ac -->
<!-- .As -->
<!-- .Bg -->
<!-- .Gp -->
<!-- .Bc -->
<!-- .Bp -->
<!-- .Bw -->
<!-- .Ch -->
<!-- .Cm -->
<!-- .Dd -->
<!-- .Dp -->
<!-- .Dc -->
<!-- .Hw -->
<variablelist>
  <varlistentry>
    <term>
      <function>icon</function>
    </term>
    <listitem>
      <para>
A pixmap image to be displayed immediately to the left of the
Dialog widget's label.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <function>label</function>
    </term>
    <listitem>
      <para>
A string to be displayed at the top of the Dialog widget.
<!-- .Mm -->
<!-- .Nc -->
<!-- .Sc -->
<!-- .Se -->
<!-- .Tr -->
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <function>value</function>
    </term>
    <listitem>
      <para>
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 initial value for <function>value</function> 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).
<!-- .Xy -->
    </para>
  </listitem>
  </varlistentry>
</variablelist>
</para>
</sect2>
<sect2 id="Constraint_Resources">
<title>Constraint Resources</title>
<para>
<!-- .LP -->
<!-- .IN "Dialog widget" "constraint resources" -->
Each child of the Dialog widget may request special layout resources
be applied to it.  These <emphasis remap='I'>constraint</emphasis> resources allow the Dialog
widget's children to specify individual layout requirements.
</para>
<para>
<!-- .LP -->
<informaltable>
  <tgroup cols='5' align='center'>
  <colspec colname='c1'/>
  <colspec colname='c2'/>
  <colspec colname='c3'/>
  <colspec colname='c4'/>
  <colspec colname='c5'/>
  <thead>
    <row>
      <entry>Name</entry>
      <entry>Class</entry>
      <entry>Type</entry>
      <entry>Notes</entry>
      <entry>Default Value</entry>
    </row>
  </thead>
  <tbody>
    <row>
      <entry>bottom</entry>
      <entry>Edge</entry>
      <entry>XawEdgeType</entry>
      <entry></entry>
      <entry>XawRubber</entry>
    </row>
    <row>
      <entry>fromHoriz</entry>
      <entry>Widget</entry>
      <entry>Widget</entry>
      <entry></entry>
      <entry>NULL (left edge of Dialog)</entry>
    </row>
    <row>
      <entry>fromVert</entry>
      <entry>Widget</entry>
      <entry>Widget </entry>
      <entry></entry>
      <entry>NULL (top edge of Dialog)</entry>
    </row>
    <row>
      <entry>horizDistance</entry>
      <entry>Thickness</entry>
      <entry>int</entry>
      <entry></entry>
      <entry><function>defaultDistance</function> resource</entry>
    </row>
    <row>
      <entry>left</entry>
      <entry>Edge</entry>
      <entry>XawEdgeType</entry>
      <entry></entry>
      <entry>XawRubber</entry>
    </row>
    <row>
      <entry>resizable</entry>
      <entry>Boolean</entry>
      <entry>Boolean</entry>
      <entry></entry>
      <entry>FALSE</entry>
    </row>
    <row>
      <entry>right</entry>
      <entry>Edge</entry>
      <entry>XawEdgeType</entry>
      <entry></entry>
      <entry>XawRubber</entry>
    </row>
    <row>
      <entry>top</entry>
      <entry>Edge</entry>
      <entry>XawEdgeType</entry>
      <entry></entry>
      <entry>XawRubber</entry>
    </row>
    <row>
      <entry>vertDistance</entry>
      <entry>Thickness</entry>
      <entry>int</entry>
      <entry></entry>
      <entry><function>defaultDistance</function> resource</entry>
    </row>
  </tbody>
  </tgroup>
</informaltable>

<literallayout class="monospaced">
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.
</literallayout>
<!-- .Bt -->
<!-- .Fh -->
<!-- .Hd -->
<!-- .Rl -->
</para>
</sect2>
<sect2 id='Dialog::Layout_Semantics'>
<title>Layout Semantics</title>
<!-- .IN "Dialog widget" "layout semantics" -->
<para>
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.
</para>
<para>
The first layout method uses the <function>fromVert</function> mand <function>fromHoriz</function>
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 <function>fromVert</function> mand <function>fromHoriz</function> mresources.  The distance
the new child is placed from its left or upper neighbor is
determined by the <function>horizDistance</function> mand <function>vertDistance</function> 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.
</para>
<para>

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 <function>bottom</function> ,
<function>top</function> , <function>left</function> , and
<function>right</function>
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 <function>XawChain</function>
<emphasis remap='I'>&lt;something&gt;</emphasis>
 is specified, the the edge
of the child will remain a fixed distance from the <emphasis remap='I'>chain</emphasis>
edge of the Dialog.  For example if <function>XawChainLeft</function>
mis specified for the <function>right</function> 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 <function>XawRubber</function> 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 <function>XawRubber</function> 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.
</para>

<para>
<!-- .LP -->
<informaltable>
  <tgroup cols='3' align='center'>
  <colspec colname='c1'/>
  <colspec colname='c2'/>
  <colspec colname='c3'/>
  <thead>
    <row>
      <entry>Edge Type</entry>
      <entry>Resource Name</entry>
      <entry>Description</entry>
    </row>
  </thead>
  <tbody>
    <row>
      <entry>XawChainBottom</entry>
      <entry>ChainBottom</entry>
      <entry>Edge remains a fixed distance from bottom of Dialog</entry>
    </row>
    <row>
      <entry>XawChainLeft</entry>
      <entry>ChainLeft</entry>
      <entry>Edge remains a fixed distance from left of Dialog</entry>
    </row>
    <row>
      <entry>XawChainRight</entry>
      <entry>ChainRight</entry>
      <entry>Edge remains a fixed distance from right of Dialog</entry>
    </row>
    <row>
      <entry>XawChainTop</entry>
      <entry>ChainTop</entry>
      <entry>Edge remains a fixed distance from top of Dialog</entry>
    </row>
    <row>
      <entry>XawRubber</entry>
      <entry>Rubber</entry>
      <entry>Edges will move a proportional distance</entry>
    </row>
  </tbody>
  </tgroup>
</informaltable>
</para>
<sect3 id="Example">
<title>Example</title>
<para>
<!-- .LP -->
If you wish to force the Dialog to never resize one or more of its children
then set <function>left</function> and <function>right</function> to <function>XawChainLeft</function> and
<function>top</function> and <function>bottom</function> to <function>XawChainTop</function>.  This will cause
the child to remain a fixed distance from the top and left
edges of the Dialog, and to never resize.
</para>
</sect3>
<sect3 id="Special_Considerations">
<title>Special Considerations</title>
<!-- .IN "Dialog widget" "special considerations" -->
<para>
<!-- .LP -->
The Dialog widget automatically sets the <function>top</function> and <function>bottom</function>
resources for all Children that are subclasses of the Command widget,
as well as the widget children that are used to contain the <function>label</function>,
<function>value</function>, and <function>icon</function>.  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.
</para>
<para>
<!-- .LP -->
The Dialog will also set <function>fromLeft</function> to the last button in the
<!-- .IN "fromLeft" "" -->
Dialog for each new button added to the Dialog widget.
</para>
<para>
<!-- .LP -->
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.
</para>
</sect3>
</sect2>
<sect2 id='Automatically_Created_Children'>
<title>Automatically Created Children.</title>
<!-- .IN "Dialog widget" "automatically created children" -->
<para>
<!-- .LP -->
The Dialog uses Label widgets to contain the <function>label</function> and <function>icon</function>.
These widgets are named <emphasis remap='I'>label</emphasis> and <emphasis remap='I'>icon</emphasis> respectively.  The
Dialog <function>value</function> is contained in an AsciiText widget whose name is
<function>value</function>.  Using <function>XtNameToWidget</function> the application can change
<!-- .IN "XtNameToWidget" "" -->
those resources associated with each of these widgets that are not
available through the Dialog widget itself.
</para>
<para>
<!-- .LP -->
</para>
</sect2>
<sect2 id='Dialog::Convenience_Routines'>
<title>Convenience Routines</title>
<para>
<!-- .LP -->
To return the character string in the text field, use
<!-- .PN XawDialogGetValueString . -->
<!-- .IN "XawDialogGetValueString" "" "@DEF@" -->
<funcsynopsis id='XawDialogGetValueString'>
<funcprototype>
  <funcdef>String<function> XawDialogGetValueString</function></funcdef>
  <paramdef>Widget<parameter> w</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the Dialog widget.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
</para>
<para>
<!-- .LP -->
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
<xref linkend='XawDialogGetValueString' xrefstyle='select: title'/> or an <xref linkend='XtGetValues' xrefstyle='select: title'/> call on the
<function>value</function> widget, when the string will be automatically freed, and
a new string is returned.  This string may be freed earlier by calling
the function <xref linkend='XawAsciiSourceFreeString' xrefstyle='select: title'/>.
<!-- .IN "XawAsciiSourceFreeString" "" -->
</para>
<para>
<!-- .LP -->
<!-- .sp -->
To add a new button to the Dialog widget use
<xref linkend='XawDialogAddButton' xrefstyle='select: title'/>.
<!-- .IN "XawDialogAddButton" "" "@DEF@" -->
<funcsynopsis id='XawDialogAddButton'>
<funcprototype>
  <funcdef>void<function> XawDialogAddButton</function></funcdef>
  <paramdef>Widget<parameter> w</parameter></paramdef>
  <paramdef>String<parameter> name</parameter></paramdef>
  <paramdef>XtCallbackProc<parameter> func</parameter></paramdef>
  <paramdef>XtPointer<parameter> client_data</parameter></paramdef>
</funcprototype>
</funcsynopsis>
<!-- .FN -->
<variablelist>
  <varlistentry>
    <term>
      <emphasis remap='I'>w</emphasis>
    </term>
    <listitem>
      <para>
Specifies the Dialog widget.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>name</emphasis>
    </term>
    <listitem>
      <para>
Specifies the name of the new Command button to be added to the Dialog.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>func</emphasis>
    </term>
    <listitem>
      <para>
Specifies a callback function to be called when this button is activated.  If
NULL is specified then no callback is added.
      </para>
    </listitem>
  </varlistentry>
  <varlistentry>
    <term>
      <emphasis remap='I'>client_data</emphasis>
    </term>
    <listitem>
      <para>
Specifies the client_data to be passed to the <emphasis remap='I'>func</emphasis>.
    </para>
  </listitem>
  </varlistentry>
</variablelist>
</para>
<para>
<!-- .LP -->
This function is merely a shorthand for the code sequence:
<!-- .sp -->
<literallayout class="monospaced">
<!-- .SM -->
<!-- .TA 1i 2i -->
<!-- .ta 1i 2i -->
{
	Widget button = XtCreateManagedWidget(name, commandWidgetClass, w, NULL, ZERO);
	XtAddCallback(button, XtNcallback, func, client_data);
}
<!-- .NL -->
</literallayout>
<!-- .sp -->

</para>
</sect2>
</sect1>