atkvalue.xml

The ATK library provides a set of interfaces for accessibility.By supporting the ATK interfaces, an

<refentry id="AtkValue">
<refmeta>
<refentrytitle role="top_of_page" id="AtkValue.top_of_page">AtkValue</refentrytitle>
<manvolnum>3</manvolnum>
<refmiscinfo>ATK Library</refmiscinfo>
</refmeta>

<refnamediv>
<refname>AtkValue</refname>
<refpurpose>The ATK interface implemented by valuators and components which display or
select a value from a bounded range of values.</refpurpose>
<!--[<xref linkend="desc" endterm="desc.title"/>]-->
</refnamediv>

<refsynopsisdiv id="AtkValue.synopsis" role="synopsis">
<title role="synopsis.title">Synopsis</title>

<synopsis>
                    <link linkend="AtkValue-struct">AtkValue</link>;
<link linkend="void">void</link>                <link linkend="atk-value-get-current-value">atk_value_get_current_value</link>         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);
<link linkend="void">void</link>                <link linkend="atk-value-get-maximum-value">atk_value_get_maximum_value</link>         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);
<link linkend="void">void</link>                <link linkend="atk-value-get-minimum-value">atk_value_get_minimum_value</link>         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);
<link linkend="gboolean">gboolean</link>            <link linkend="atk-value-set-current-value">atk_value_set_current_value</link>         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         const <link linkend="GValue">GValue</link> *value);
<link linkend="void">void</link>                <link linkend="atk-value-get-minimum-increment">atk_value_get_minimum_increment</link>     (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);
</synopsis>
</refsynopsisdiv>

<refsect1 id="AtkValue.object-hierarchy" role="object_hierarchy">
<title role="object_hierarchy.title">Object Hierarchy</title>
<synopsis>
  <link linkend="GInterface">GInterface</link>
   +----AtkValue
</synopsis>

</refsect1>




<refsect1 id="AtkValue.implementations" role="implementations">
<title role="implementations.title">Known Implementations</title>
<para>
AtkValue is implemented by
 <link linkend="AtkNoOpObject">AtkNoOpObject</link>.</para>

</refsect1>




<refsect1 id="AtkValue.description" role="desc">
<title role="desc.title">Description</title>
<para>
<link linkend="AtkValue"><type>AtkValue</type></link> should be implemented for components which either display a
value from a bounded range, or which allow the user to specify a value
from a bounded range, or both.  For instance, most sliders and range
controls, as well as dials, should have <link linkend="AtkObject"><type>AtkObject</type></link> representations which
implement <link linkend="AtkValue"><type>AtkValue</type></link> on the component's behalf.  <link linkend="AtKValues"><type>AtKValues</type></link> may be
read-only, in which case attempts to alter the value return FALSE to
indicate failure.
</para>
</refsect1>

<refsect1 id="AtkValue.details" role="details">
<title role="details.title">Details</title>
<refsect2 id="AtkValue-struct" role="struct">
<title>AtkValue</title>
<indexterm zone="AtkValue-struct"><primary>AtkValue</primary></indexterm><programlisting>typedef struct _AtkValue AtkValue;</programlisting>
<para>
The AtkValue structure does not contain any fields.

</para></refsect2>
<refsect2 id="atk-value-get-current-value" role="function">
<title>atk_value_get_current_value ()</title>
<indexterm zone="atk-value-get-current-value"><primary>atk_value_get_current_value</primary></indexterm><programlisting><link linkend="void">void</link>                atk_value_get_current_value         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);</programlisting>
<para>
Gets the value of this object.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>obj</parameter>&nbsp;:</term>
<listitem><simpara> a GObject instance that implements AtkValueIface
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter>&nbsp;:</term>
<listitem><simpara> a <link linkend="GValue"><type>GValue</type></link> representing the current accessible value
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2 id="atk-value-get-maximum-value" role="function">
<title>atk_value_get_maximum_value ()</title>
<indexterm zone="atk-value-get-maximum-value"><primary>atk_value_get_maximum_value</primary></indexterm><programlisting><link linkend="void">void</link>                atk_value_get_maximum_value         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);</programlisting>
<para>
Gets the maximum value of this object.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>obj</parameter>&nbsp;:</term>
<listitem><simpara> a GObject instance that implements AtkValueIface
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter>&nbsp;:</term>
<listitem><simpara> a <link linkend="GValue"><type>GValue</type></link> representing the maximum accessible value
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2 id="atk-value-get-minimum-value" role="function">
<title>atk_value_get_minimum_value ()</title>
<indexterm zone="atk-value-get-minimum-value"><primary>atk_value_get_minimum_value</primary></indexterm><programlisting><link linkend="void">void</link>                atk_value_get_minimum_value         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);</programlisting>
<para>
Gets the minimum value of this object.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>obj</parameter>&nbsp;:</term>
<listitem><simpara> a GObject instance that implements AtkValueIface
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter>&nbsp;:</term>
<listitem><simpara> a <link linkend="GValue"><type>GValue</type></link> representing the minimum accessible value
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2 id="atk-value-set-current-value" role="function">
<title>atk_value_set_current_value ()</title>
<indexterm zone="atk-value-set-current-value"><primary>atk_value_set_current_value</primary></indexterm><programlisting><link linkend="gboolean">gboolean</link>            atk_value_set_current_value         (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         const <link linkend="GValue">GValue</link> *value);</programlisting>
<para>
Sets the value of this object.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>obj</parameter>&nbsp;:</term>
<listitem><simpara> a GObject instance that implements AtkValueIface
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter>&nbsp;:</term>
<listitem><simpara> a <link linkend="GValue"><type>GValue</type></link> which is the desired new accessible value.
</simpara></listitem></varlistentry>
<varlistentry><term><emphasis>Returns</emphasis>&nbsp;:</term><listitem><simpara> <link linkend="TRUE:CAPS"><literal>TRUE</literal></link> if new value is successfully set, <link linkend="FALSE:CAPS"><literal>FALSE</literal></link> otherwise.
</simpara></listitem></varlistentry>
</variablelist></refsect2>
<refsect2 id="atk-value-get-minimum-increment" role="function" condition="since:ATK 1.12">
<title>atk_value_get_minimum_increment ()</title>
<indexterm zone="atk-value-get-minimum-increment" role="ATK 1.12"><primary>atk_value_get_minimum_increment</primary></indexterm><programlisting><link linkend="void">void</link>                atk_value_get_minimum_increment     (<link linkend="AtkValue">AtkValue</link> *obj,
                                                         <link linkend="GValue">GValue</link> *value);</programlisting>
<para>
Gets the minimum increment by which the value of this object may be changed.  If zero,
the minimum increment is undefined, which may mean that it is limited only by the 
floating point precision of the platform.</para>
<para>

</para><variablelist role="params">
<varlistentry><term><parameter>obj</parameter>&nbsp;:</term>
<listitem><simpara> a GObject instance that implements AtkValueIface
</simpara></listitem></varlistentry>
<varlistentry><term><parameter>value</parameter>&nbsp;:</term>
<listitem><simpara> a <link linkend="GValue"><type>GValue</type></link> representing the minimum increment by which the accessible value may be changed
</simpara></listitem></varlistentry>
</variablelist><para role="since">Since  ATK 1.12
</para></refsect2>

</refsect1>




</refentry>