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<h1 class="title">QXmlItem Class Reference</h1>
<!-- $$$QXmlItem-brief -->
<p>The QXmlItem class contains either an XML node or an atomic value. <a href="#details">More...</a></p>
<!-- @@@QXmlItem -->
<pre class="cpp"> <span class="preprocessor">#include &lt;QXmlItem&gt;</span></pre><p><b>Note:</b> All functions in this class are <a href="threads-reentrancy.html#reentrant">reentrant</a>.</p>
<p>This class was introduced in Qt 4.4.</p>
<ul>
<li><a href="qxmlitem-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-types"></a>
<h2>Public Types</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> typedef </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#Iterator-typedef">Iterator</a></b></td></tr>
</table>
<a name="public-functions"></a>
<h2>Public Functions</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#QXmlItem">QXmlItem</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#QXmlItem-2">QXmlItem</a></b> ( const QXmlItem &amp; <i>other</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#QXmlItem-3">QXmlItem</a></b> ( const QXmlNodeModelIndex &amp; <i>node</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#QXmlItem-4">QXmlItem</a></b> ( const QVariant &amp; <i>atomicValue</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#dtor.QXmlItem">~QXmlItem</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#isAtomicValue">isAtomicValue</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#isNode">isNode</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#isNull">isNull</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QVariant </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#toAtomicValue">toAtomicValue</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QXmlNodeModelIndex </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#toNodeModelIndex">toNodeModelIndex</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QXmlItem &amp; </td><td class="memItemRight bottomAlign"><b><a href="qxmlitem.html#operator-eq">operator=</a></b> ( const QXmlItem &amp; <i>other</i> )</td></tr>
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<a name="details"></a>
<!-- $$$QXmlItem-description -->
<div class="descr">
<h2>Detailed Description</h2>
<p>The QXmlItem class contains either an XML node or an atomic value.</p>
<p>In <a href="xmlprocessing.html">XQuery</a>, all expressions evaluate to a sequence of items, where each item is either an XML node or an atomic value. The query in the following snippet evaluates to sequence of five items.</p>
<pre class="cpp"> &lt;aNode/&gt;,
xs:base64Binary(&quot;FFFF&quot;),
current-date(),
3e3, (: A floating point value :)
attribute {&quot;name&quot;} {()}</pre>
<p>The five items are: An element, an atomic value (binary data encoded in base64), a date, a float, and an attribute.</p>
<p>QXmlItem is the class that represents these <a href="xmlprocessing.html">XQuery</a> items in the <a href="qtxmlpatterns.html">QtXmlPatterns</a> API. A non-null instance of QXmlItem is either a node or an atomic value. Calling <a href="qxmlitem.html#isNode">isNode</a>() or <a href="qxmlitem.html#isAtomicValue">isAtomicValue</a>() tells you which it is. Atomic values are represented elsewhere in the Qt API as instances of <a href="qvariant.html">QVariant</a>, and an instance of QXmlItem that represents an atomic value can be converted to a <a href="qvariant.html">QVariant</a> by calling <a href="qxmlitem.html#toAtomicValue">toAtomicValue</a>(). A QXmlItem that wraps a node is represented elsewhere as an instance of <a href="qxmlnodemodelindex.html">QXmlNodeModelIndex</a>. A node QXmlItem can be converted to a <a href="qxmlnodemodelindex.html">QXmlNodeModelIndex</a> by calling <a href="qxmlitem.html#toNodeModelIndex">toNodeModelIndex</a>().</p>
<p>A default constructed QXmlItem instance is neither a node nor an atomic value. It is considered null, in which case <a href="qxmlitem.html#isNull">isNull</a>() returns true.</p>
<p>An instance of QXmlItem will be left dangling if the <a href="qabstractxmlnodemodel.html">XML node model</a> it refers to is deleted, if it is a <a href="qxmlnodemodelindex.html">QXmlNodeModelIndex</a>.</p>
</div>
<!-- @@@QXmlItem -->
<div class="types">
<h2>Member Type Documentation</h2>
<!-- $$$Iterator -->
<h3 class="fn"><a name="Iterator-typedef"></a>typedef QXmlItem::<span class="name">Iterator</span></h3>
<p>A QAbstractXmlForwardIterator over <a href="qxmlitem.html">QXmlItem</a>.</p>
<!-- @@@Iterator -->
</div>
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QXmlItem[overload1]$$$QXmlItem -->
<h3 class="fn"><a name="QXmlItem"></a>QXmlItem::<span class="name">QXmlItem</span> ()</h3>
<p>Constructs a null <a href="qxmlitem.html">QXmlItem</a> that is neither a node nor an atomic value. <a href="qxmlitem.html#isNull">isNull</a>() returns true for a default constructed instance.</p>
<!-- @@@QXmlItem -->
<!-- $$$QXmlItem$$$QXmlItemconstQXmlItem& -->
<h3 class="fn"><a name="QXmlItem-2"></a>QXmlItem::<span class="name">QXmlItem</span> ( const <span class="type">QXmlItem</span> &amp; <i>other</i> )</h3>
<p>The copy constructor constructs a copy of <i>other</i>.</p>
<!-- @@@QXmlItem -->
<!-- $$$QXmlItem$$$QXmlItemconstQXmlNodeModelIndex& -->
<h3 class="fn"><a name="QXmlItem-3"></a>QXmlItem::<span class="name">QXmlItem</span> ( const <span class="type"><a href="qxmlnodemodelindex.html">QXmlNodeModelIndex</a></span> &amp; <i>node</i> )</h3>
<p>Constructs a node <a href="qxmlitem.html">QXmlItem</a> that is a copy of <i>node</i>.</p>
<p><b>See also </b><a href="qxmlitem.html#isNode">isNode</a>().</p>
<!-- @@@QXmlItem -->
<!-- $$$QXmlItem$$$QXmlItemconstQVariant& -->
<h3 class="fn"><a name="QXmlItem-4"></a>QXmlItem::<span class="name">QXmlItem</span> ( const <span class="type"><a href="qvariant.html">QVariant</a></span> &amp; <i>atomicValue</i> )</h3>
<p>Constructs an atomic value <a href="qxmlitem.html">QXmlItem</a> with <i>atomicValue</i>.</p>
<p><b>See also </b><a href="qxmlitem.html#isAtomicValue">isAtomicValue</a>().</p>
<!-- @@@QXmlItem -->
<!-- $$$~QXmlItem[overload1]$$$~QXmlItem -->
<h3 class="fn"><a name="dtor.QXmlItem"></a>QXmlItem::<span class="name">~QXmlItem</span> ()</h3>
<p>Destructor.</p>
<!-- @@@~QXmlItem -->
<!-- $$$isAtomicValue[overload1]$$$isAtomicValue -->
<h3 class="fn"><a name="isAtomicValue"></a><span class="type">bool</span> QXmlItem::<span class="name">isAtomicValue</span> () const</h3>
<p>Returns true if this item is an atomic value. Returns false if it is a node or null.</p>
<p><b>See also </b><a href="qxmlitem.html#isNull">isNull</a>() and <a href="qxmlitem.html#isNode">isNode</a>().</p>
<!-- @@@isAtomicValue -->
<!-- $$$isNode[overload1]$$$isNode -->
<h3 class="fn"><a name="isNode"></a><span class="type">bool</span> QXmlItem::<span class="name">isNode</span> () const</h3>
<p>Returns true if this item is a Node. Returns false if it is an atomic value or null.</p>
<p><b>See also </b><a href="qxmlitem.html#isNull">isNull</a>() and <a href="qxmlitem.html#isAtomicValue">isAtomicValue</a>().</p>
<!-- @@@isNode -->
<!-- $$$isNull[overload1]$$$isNull -->
<h3 class="fn"><a name="isNull"></a><span class="type">bool</span> QXmlItem::<span class="name">isNull</span> () const</h3>
<p>Returns true if this <a href="qxmlitem.html">QXmlItem</a> is neither a node nor an atomic value. Default constructed instances of <a href="qxmlitem.html">QXmlItem</a> are null.</p>
<!-- @@@isNull -->
<!-- $$$toAtomicValue[overload1]$$$toAtomicValue -->
<h3 class="fn"><a name="toAtomicValue"></a><span class="type"><a href="qvariant.html">QVariant</a></span> QXmlItem::<span class="name">toAtomicValue</span> () const</h3>
<p>If this <a href="qxmlitem.html">QXmlItem</a> represents an atomic value, it is converted to an appropriate <a href="qvariant.html">QVariant</a> and returned. If this <a href="qxmlitem.html">QXmlItem</a> is not an atomic value, the return value is a default constructed <a href="qvariant.html">QVariant</a>. You can call <a href="qxmlitem.html#isAtomicValue">isAtomicValue</a>() to test whether the item is an atomic value.</p>
<p><b>See also </b><a href="qxmlitem.html#isAtomicValue">isAtomicValue</a>().</p>
<!-- @@@toAtomicValue -->
<!-- $$$toNodeModelIndex[overload1]$$$toNodeModelIndex -->
<h3 class="fn"><a name="toNodeModelIndex"></a><span class="type"><a href="qxmlnodemodelindex.html">QXmlNodeModelIndex</a></span> QXmlItem::<span class="name">toNodeModelIndex</span> () const</h3>
<p>If this <a href="qxmlitem.html">QXmlItem</a> represents a node, it returns the item as a <a href="qxmlnodemodelindex.html">QXmlNodeModelIndex</a>. If this <a href="qxmlitem.html">QXmlItem</a> is not a node, the return value is undefined. You can call <a href="qxmlitem.html#isNode">isNode</a>() to test whether the item is a node.</p>
<p><b>See also </b><a href="qxmlitem.html#isNode">isNode</a>().</p>
<!-- @@@toNodeModelIndex -->
<!-- $$$operator=[overload1]$$$operator=constQXmlItem& -->
<h3 class="fn"><a name="operator-eq"></a><span class="type">QXmlItem</span> &amp; QXmlItem::<span class="name">operator=</span> ( const <span class="type">QXmlItem</span> &amp; <i>other</i> )</h3>
<p>Assigns <i>other</i> to <tt>this</tt>.</p>
<!-- @@@operator= -->
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