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<refentry id="at-spi-cspi-AccessibleComponent-Interface">
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<refentrytitle role="top_of_page" id="at-spi-cspi-AccessibleComponent-Interface.top_of_page">AccessibleComponent Interface</refentrytitle>
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<manvolnum>3</manvolnum>
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<refmiscinfo>AT-SPI-CSPI Library</refmiscinfo>
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<refname>AccessibleComponent Interface</refname>
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<refpurpose>An interface implemented by objects which occupy area on screen.</refpurpose>
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<refsynopsisdiv id="at-spi-cspi-AccessibleComponent-Interface.synopsis" role="synopsis">
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<title role="synopsis.title">Synopsis</title>
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enum <link linkend="AccessibleCoordType">AccessibleCoordType</link>;
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enum <link linkend="AccessibleComponentLayer">AccessibleComponentLayer</link>;
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<link linkend="void">void</link> <link linkend="AccessibleComponent-ref">AccessibleComponent_ref</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);
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<link linkend="void">void</link> <link linkend="AccessibleComponent-unref">AccessibleComponent_unref</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);
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<link linkend="SPIBoolean">SPIBoolean</link> <link linkend="AccessibleComponent-contains">AccessibleComponent_contains</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> x,
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long <link linkend="int">int</link> y,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);
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<link linkend="Accessible">Accessible</link> * <link linkend="AccessibleComponent-getAccessibleAtPoint">AccessibleComponent_getAccessibleAtPoint</link>
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(<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> x,
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long <link linkend="int">int</link> y,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);
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<link linkend="void">void</link> <link linkend="AccessibleComponent-getExtents">AccessibleComponent_getExtents</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> *x,
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long <link linkend="int">int</link> *y,
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long <link linkend="int">int</link> *width,
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long <link linkend="int">int</link> *height,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);
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<link linkend="void">void</link> <link linkend="AccessibleComponent-getPosition">AccessibleComponent_getPosition</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> *x,
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long <link linkend="int">int</link> *y,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);
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<link linkend="void">void</link> <link linkend="AccessibleComponent-getSize">AccessibleComponent_getSize</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> *width,
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long <link linkend="int">int</link> *height);
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<link linkend="AccessibleComponentLayer">AccessibleComponentLayer</link> <link linkend="AccessibleComponent-getLayer">AccessibleComponent_getLayer</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);
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<link linkend="short">short</link> <link linkend="AccessibleComponent-getMDIZOrder">AccessibleComponent_getMDIZOrder</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);
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<link linkend="SPIBoolean">SPIBoolean</link> <link linkend="AccessibleComponent-grabFocus">AccessibleComponent_grabFocus</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);
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<link linkend="double">double</link> <link linkend="AccessibleComponent-getAlpha">AccessibleComponent_getAlpha</link> (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);
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<refsect1 id="at-spi-cspi-AccessibleComponent-Interface.description" role="desc">
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<title role="desc.title">Description</title>
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The Component interface is implemented by objects which are visible, or are
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potentially visible, onscreen. The interface exposes onscreen bounds, the
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approximate "layer" in which the object resides, sometimes including z-order
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information, and allows objects to explicitly be told to request focus.
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<refsect1 id="at-spi-cspi-AccessibleComponent-Interface.details" role="details">
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<title role="details.title">Details</title>
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<refsect2 id="AccessibleCoordType" role="enum">
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<title>enum AccessibleCoordType</title>
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<indexterm zone="AccessibleCoordType"><primary sortas="AccessibleCoordType">AccessibleCoordType</primary></indexterm><programlisting>typedef enum {
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SPI_COORD_TYPE_SCREEN,
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} AccessibleCoordType;
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Specifies how xy coordinates are to be interpreted. Used by functions such
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as <link linkend="AccessibleComponent-getPosition"><function>AccessibleComponent_getPosition()</function></link> and <link linkend="AccessibleText-getCharacterExtents"><function>AccessibleText_getCharacterExtents()</function></link></para>
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</para><variablelist role="enum">
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<varlistentry id="SPI-COORD-TYPE-SCREEN--CAPS" role="constant">
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<term><literal>SPI_COORD_TYPE_SCREEN</literal></term>
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<listitem><simpara> specifies xy coordinates relative to the screen
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<varlistentry id="SPI-COORD-TYPE-WINDOW--CAPS" role="constant">
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<term><literal>SPI_COORD_TYPE_WINDOW</literal></term>
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<listitem><simpara> specifies xy coordinates relative to an object's
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponentLayer" role="enum">
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<title>enum AccessibleComponentLayer</title>
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<indexterm zone="AccessibleComponentLayer"><primary sortas="AccessibleComponentLayer">AccessibleComponentLayer</primary></indexterm><programlisting>typedef enum {
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SPI_LAYER_LAST_DEFINED
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} AccessibleComponentLayer;
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Describes the layer of a component.
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These enumerated "layer values" are used when determining which UI
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rendering layer a component is drawn into, which can help in making
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determinations of when components occlude one another.</para>
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</para><variablelist role="enum">
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<varlistentry id="SPI-LAYER-INVALID--CAPS" role="constant">
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<term><literal>SPI_LAYER_INVALID</literal></term>
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<listitem><simpara> The layer cannot be determined or is somehow undefined.
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-BACKGROUND--CAPS" role="constant">
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<term><literal>SPI_LAYER_BACKGROUND</literal></term>
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<listitem><simpara> Component belongs to the destop background.
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-CANVAS--CAPS" role="constant">
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<term><literal>SPI_LAYER_CANVAS</literal></term>
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<listitem><simpara> Component is a canvas backdrop or drawing area.
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-WIDGET--CAPS" role="constant">
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<term><literal>SPI_LAYER_WIDGET</literal></term>
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<listitem><simpara> Component is a 'normal' widget.
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-MDI--CAPS" role="constant">
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<term><literal>SPI_LAYER_MDI</literal></term>
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<listitem><simpara> Component is drawn in the MDI layer and may have valid
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Z-information relative to other MDI-layer components.
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-POPUP--CAPS" role="constant">
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<term><literal>SPI_LAYER_POPUP</literal></term>
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<listitem><simpara> Component is in the popup layer, above other widgets and
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-OVERLAY--CAPS" role="constant">
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<term><literal>SPI_LAYER_OVERLAY</literal></term>
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<listitem><simpara> Component is in the overlay plane - this value is reserved
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-WINDOW--CAPS" role="constant">
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<term><literal>SPI_LAYER_WINDOW</literal></term>
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<listitem><simpara> Component is in the window layer and have valid Z-information
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relative to other window-layer components.
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</simpara></listitem>
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<varlistentry id="SPI-LAYER-LAST-DEFINED--CAPS" role="constant">
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<term><literal>SPI_LAYER_LAST_DEFINED</literal></term>
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<listitem><simpara> Used to determine the last valid value in the enum,
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should not be encountered.
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</simpara></listitem>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-ref" role="function">
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<title>AccessibleComponent_ref ()</title>
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<indexterm zone="AccessibleComponent-ref"><primary sortas="AccessibleComponent_ref">AccessibleComponent_ref</primary></indexterm><programlisting><link linkend="void">void</link> AccessibleComponent_ref (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);</programlisting>
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Increment the reference count for an <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to an object implementing <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> on which to operate.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-unref" role="function">
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<title>AccessibleComponent_unref ()</title>
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<indexterm zone="AccessibleComponent-unref"><primary sortas="AccessibleComponent_unref">AccessibleComponent_unref</primary></indexterm><programlisting><link linkend="void">void</link> AccessibleComponent_unref (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);</programlisting>
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Decrement the reference count for an <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the object implementing <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> on which to operate.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-contains" role="function">
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<title>AccessibleComponent_contains ()</title>
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<indexterm zone="AccessibleComponent-contains"><primary sortas="AccessibleComponent_contains">AccessibleComponent_contains</primary></indexterm><programlisting><link linkend="SPIBoolean">SPIBoolean</link> AccessibleComponent_contains (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> x,
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long <link linkend="int">int</link> y,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);</programlisting>
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Query whether a given <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> contains a particular point.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>x</parameter> :</term>
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<listitem><simpara> a <link linkend="long"><type>long</type></link> specifying the x coordinate in question.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>y</parameter> :</term>
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<listitem><simpara> a <link linkend="long"><type>long</type></link> specifying the y coordinate in question.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>ctype</parameter> :</term>
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<listitem><simpara> the desired coordinate system of the point (<parameter>x</parameter>, <parameter>y</parameter>)
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(e.g. SPI_COORD_TYPE_WINDOW, SPI_COORD_TYPE_SCREEN).
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</simpara></listitem></varlistentry>
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<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> a <link linkend="TRUE--CAPS"><type>TRUE</type></link> if the specified component contains the point (<parameter>x</parameter>, <parameter>y</parameter>),
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otherwise <link linkend="FALSE--CAPS"><type>FALSE</type></link>.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getAccessibleAtPoint" role="function">
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<title>AccessibleComponent_getAccessibleAtPoint ()</title>
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<indexterm zone="AccessibleComponent-getAccessibleAtPoint"><primary sortas="AccessibleComponent_getAccessibleAtPoint">AccessibleComponent_getAccessibleAtPoint</primary></indexterm><programlisting><link linkend="Accessible">Accessible</link> * AccessibleComponent_getAccessibleAtPoint
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(<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> x,
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long <link linkend="int">int</link> y,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);</programlisting>
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Get the accessible child at a given coordinate within an <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>x</parameter> :</term>
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<listitem><simpara> a <link linkend="long"><type>long</type></link> specifying the x coordinate of the point in question.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>y</parameter> :</term>
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<listitem><simpara> a <link linkend="long"><type>long</type></link> specifying the y coordinate of the point in question.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>ctype</parameter> :</term>
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<listitem><simpara> the coordinate system of the point (<parameter>x</parameter>, <parameter>y</parameter>)
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(e.g. SPI_COORD_TYPE_WINDOW, SPI_COORD_TYPE_SCREEN).
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</simpara></listitem></varlistentry>
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<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> a pointer to an <link linkend="Accessible"><type>Accessible</type></link> child of the specified component which
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contains the point (<parameter>x</parameter>, <parameter>y</parameter>), or NULL of no child contains the point.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getExtents" role="function">
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<title>AccessibleComponent_getExtents ()</title>
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<indexterm zone="AccessibleComponent-getExtents"><primary sortas="AccessibleComponent_getExtents">AccessibleComponent_getExtents</primary></indexterm><programlisting><link linkend="void">void</link> AccessibleComponent_getExtents (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> *x,
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long <link linkend="int">int</link> *y,
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long <link linkend="int">int</link> *width,
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long <link linkend="int">int</link> *height,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);</programlisting>
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Get the bounding box of the specified <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>x</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the minimum x coordinate will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>y</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the minimum y coordinate will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>width</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the x extents (width) will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>height</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the y extents (height) will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>ctype</parameter> :</term>
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<listitem><simpara> the desired coordinate system into which to return the results,
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(e.g. SPI_COORD_TYPE_WINDOW, SPI_COORD_TYPE_SCREEN).
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getPosition" role="function">
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<title>AccessibleComponent_getPosition ()</title>
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<indexterm zone="AccessibleComponent-getPosition"><primary sortas="AccessibleComponent_getPosition">AccessibleComponent_getPosition</primary></indexterm><programlisting><link linkend="void">void</link> AccessibleComponent_getPosition (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> *x,
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long <link linkend="int">int</link> *y,
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<link linkend="AccessibleCoordType">AccessibleCoordType</link> ctype);</programlisting>
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Get the minimum x and y coordinates of the specified <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>x</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the minimum x coordinate will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>y</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the minimum y coordinate will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>ctype</parameter> :</term>
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<listitem><simpara> the desired coordinate system into which to return the results,
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(e.g. SPI_COORD_TYPE_WINDOW, SPI_COORD_TYPE_SCREEN).
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getSize" role="function">
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<title>AccessibleComponent_getSize ()</title>
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<indexterm zone="AccessibleComponent-getSize"><primary sortas="AccessibleComponent_getSize">AccessibleComponent_getSize</primary></indexterm><programlisting><link linkend="void">void</link> AccessibleComponent_getSize (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj,
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long <link linkend="int">int</link> *width,
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long <link linkend="int">int</link> *height);</programlisting>
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Get the size of the specified <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>width</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the x extents (width) will be returned.
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</simpara></listitem></varlistentry>
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<varlistentry><term><parameter>height</parameter> :</term>
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<listitem><simpara> a pointer to a <link linkend="long"><type>long</type></link> into which the y extents (height) will be returned.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getLayer" role="function">
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<title>AccessibleComponent_getLayer ()</title>
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<indexterm zone="AccessibleComponent-getLayer"><primary sortas="AccessibleComponent_getLayer">AccessibleComponent_getLayer</primary></indexterm><programlisting><link linkend="AccessibleComponentLayer">AccessibleComponentLayer</link> AccessibleComponent_getLayer (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);</programlisting>
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Query which layer the component is painted into, to help determine its
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visibility in terms of stacking order.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> the <link linkend="AccessibleComponentLayer"><type>AccessibleComponentLayer</type></link> into which this component is painted.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getMDIZOrder" role="function">
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<title>AccessibleComponent_getMDIZOrder ()</title>
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<indexterm zone="AccessibleComponent-getMDIZOrder"><primary sortas="AccessibleComponent_getMDIZOrder">AccessibleComponent_getMDIZOrder</primary></indexterm><programlisting><link linkend="short">short</link> AccessibleComponent_getMDIZOrder (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);</programlisting>
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Query the z stacking order of a component which is in the MDI or window
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layer. (Bigger z-order numbers mean nearer the top)</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to query.
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</simpara></listitem></varlistentry>
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<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> a short integer indicating the stacking order of the component
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in the MDI layer, or -1 if the component is not in the MDI layer.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-grabFocus" role="function">
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<title>AccessibleComponent_grabFocus ()</title>
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<indexterm zone="AccessibleComponent-grabFocus"><primary sortas="AccessibleComponent_grabFocus">AccessibleComponent_grabFocus</primary></indexterm><programlisting><link linkend="SPIBoolean">SPIBoolean</link> AccessibleComponent_grabFocus (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);</programlisting>
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Attempt to set the keyboard input focus to the specified
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<link linkend="AccessibleComponent"><type>AccessibleComponent</type></link>.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> a pointer to the <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> on which to operate.
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</simpara></listitem></varlistentry>
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<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> <link linkend="TRUE--CAPS"><type>TRUE</type></link> if successful, <link linkend="FALSE--CAPS"><type>FALSE</type></link> otherwise.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>
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<refsect2 id="AccessibleComponent-getAlpha" role="function">
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<title>AccessibleComponent_getAlpha ()</title>
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<indexterm zone="AccessibleComponent-getAlpha"><primary sortas="AccessibleComponent_getAlpha">AccessibleComponent_getAlpha</primary></indexterm><programlisting><link linkend="double">double</link> AccessibleComponent_getAlpha (<link linkend="AccessibleComponent">AccessibleComponent</link> *obj);</programlisting>
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Get the opacity/alpha value of a component, if alpha blending is in use.</para>
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</para><variablelist role="params">
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<varlistentry><term><parameter>obj</parameter> :</term>
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<listitem><simpara> The <link linkend="AccessibleComponent"><type>AccessibleComponent</type></link> to be queried.
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</simpara></listitem></varlistentry>
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<varlistentry><term><emphasis>Returns</emphasis> :</term><listitem><simpara> the opacity value of a component, as a double between 0.0 and 1.0.
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</simpara></listitem></varlistentry>
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</variablelist></refsect2>