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<li class="level1"><a href="#public-functions">Public Functions</a></li>
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<h1 class="title">QDeclarativePropertyMap Class Reference</h1>
<!-- $$$QDeclarativePropertyMap-brief -->
<p>The QDeclarativePropertyMap class allows you to set key-value pairs that can be used in QML bindings. <a href="#details">More...</a></p>
<!-- @@@QDeclarativePropertyMap -->
<pre class="cpp"> <span class="preprocessor">#include <QDeclarativePropertyMap></span></pre><p><b>Inherits: </b><a href="qobject.html">QObject</a>.</p>
<p>This class was introduced in Qt 4.7.</p>
<ul>
<li><a href="qdeclarativepropertymap-members.html">List of all members, including inherited members</a></li>
</ul>
<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="qdeclarativepropertymap.html#QDeclarativePropertyMap">QDeclarativePropertyMap</a></b> ( QObject * <i>parent</i> = 0 )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#dtor.QDeclarativePropertyMap">~QDeclarativePropertyMap</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#clear">clear</a></b> ( const QString & <i>key</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#contains">contains</a></b> ( const QString & <i>key</i> ) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#count">count</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#insert">insert</a></b> ( const QString & <i>key</i>, const QVariant & <i>value</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#isEmpty">isEmpty</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QStringList </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#keys">keys</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#size">size</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QVariant </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#value">value</a></b> ( const QString & <i>key</i> ) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QVariant & </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#operator-5b-5d">operator[]</a></b> ( const QString & <i>key</i> )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QVariant </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#operator-5b-5d-2">operator[]</a></b> ( const QString & <i>key</i> ) const</td></tr>
</table>
<ul>
<li class="fn">29 public functions inherited from <a href="qobject.html#public-functions">QObject</a></li>
</ul>
<a name="signals"></a>
<h2>Signals</h2>
<table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativepropertymap.html#valueChanged">valueChanged</a></b> ( const QString & <i>key</i>, const QVariant & <i>value</i> )</td></tr>
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<ul>
<li class="fn">1 signal inherited from <a href="qobject.html#signals">QObject</a></li>
</ul>
<h3>Additional Inherited Members</h3>
<ul>
<li class="fn">1 property inherited from <a href="qobject.html#properties">QObject</a></li>
<li class="fn">1 public slot inherited from <a href="qobject.html#public-slots">QObject</a></li>
<li class="fn">7 static public members inherited from <a href="qobject.html#static-public-members">QObject</a></li>
<li class="fn">8 protected functions inherited from <a href="qobject.html#protected-functions">QObject</a></li>
</ul>
<a name="details"></a>
<!-- $$$QDeclarativePropertyMap-description -->
<div class="descr">
<h2>Detailed Description</h2>
<p>The QDeclarativePropertyMap class allows you to set key-value pairs that can be used in QML bindings.</p>
<p>QDeclarativePropertyMap provides a convenient way to expose domain data to the UI layer. The following example shows how you might declare data in C++ and then access it in QML.</p>
<p>In the C++ file:</p>
<pre class="cpp"> <span class="comment">// create our data</span>
<span class="type">QDeclarativePropertyMap</span> ownerData;
ownerData<span class="operator">.</span><a href="qdeclarativepropertymap.html#insert">insert</a>(<span class="string">"name"</span><span class="operator">,</span> <span class="type"><a href="qvariant.html">QVariant</a></span>(<span class="type"><a href="qstring.html">QString</a></span>(<span class="string">"John Smith"</span>)));
ownerData<span class="operator">.</span><a href="qdeclarativepropertymap.html#insert">insert</a>(<span class="string">"phone"</span><span class="operator">,</span> <span class="type"><a href="qvariant.html">QVariant</a></span>(<span class="type"><a href="qstring.html">QString</a></span>(<span class="string">"555-5555"</span>)));
<span class="comment">// expose it to the UI layer</span>
<span class="type"><a href="qdeclarativeview.html">QDeclarativeView</a></span> view;
<span class="type"><a href="qdeclarativecontext.html">QDeclarativeContext</a></span> <span class="operator">*</span>ctxt <span class="operator">=</span> view<span class="operator">.</span>rootContext();
ctxt<span class="operator">-</span><span class="operator">></span>setContextProperty(<span class="string">"owner"</span><span class="operator">,</span> <span class="operator">&</span>ownerData);
view<span class="operator">.</span>setSource(<span class="type"><a href="qurl.html">QUrl</a></span><span class="operator">::</span>fromLocalFile(<span class="string">"main.qml"</span>));
view<span class="operator">.</span>show();</pre>
<p>Then, in <tt>main.qml</tt>:</p>
<pre class="cpp"> Text { text: owner<span class="operator">.</span>name <span class="operator">+</span> <span class="string">" "</span> <span class="operator">+</span> owner<span class="operator">.</span>phone }</pre>
<p>The binding is dynamic - whenever a key's value is updated, anything bound to that key will be updated as well.</p>
<p>To detect value changes made in the UI layer you can connect to the <a href="qdeclarativepropertymap.html#valueChanged">valueChanged</a>() signal. However, note that <a href="qdeclarativepropertymap.html#valueChanged">valueChanged</a>() is <b>NOT</b> emitted when changes are made by calling <a href="qdeclarativepropertymap.html#insert">insert</a>() or <a href="qdeclarativepropertymap.html#clear">clear</a>() - it is only emitted when a value is updated from QML.</p>
<p><b>Note:</b> It is not possible to remove keys from the map; once a key has been added, you can only modify or clear its associated value.</p>
</div>
<!-- @@@QDeclarativePropertyMap -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QDeclarativePropertyMap[overload1]$$$QDeclarativePropertyMapQObject* -->
<h3 class="fn"><a name="QDeclarativePropertyMap"></a>QDeclarativePropertyMap::<span class="name">QDeclarativePropertyMap</span> ( <span class="type"><a href="qobject.html">QObject</a></span> * <i>parent</i> = 0 )</h3>
<p>Constructs a bindable map with parent object <i>parent</i>.</p>
<!-- @@@QDeclarativePropertyMap -->
<!-- $$$~QDeclarativePropertyMap[overload1]$$$~QDeclarativePropertyMap -->
<h3 class="fn"><a name="dtor.QDeclarativePropertyMap"></a>QDeclarativePropertyMap::<span class="name">~QDeclarativePropertyMap</span> ()<tt> [virtual]</tt></h3>
<p>Destroys the bindable map.</p>
<!-- @@@~QDeclarativePropertyMap -->
<!-- $$$clear[overload1]$$$clearconstQString& -->
<h3 class="fn"><a name="clear"></a><span class="type">void</span> QDeclarativePropertyMap::<span class="name">clear</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i> )</h3>
<p>Clears the value (if any) associated with <i>key</i>.</p>
<!-- @@@clear -->
<!-- $$$contains[overload1]$$$containsconstQString& -->
<h3 class="fn"><a name="contains"></a><span class="type">bool</span> QDeclarativePropertyMap::<span class="name">contains</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i> ) const</h3>
<p>Returns true if the map contains <i>key</i>.</p>
<p><b>See also </b><a href="qdeclarativepropertymap.html#size">size</a>().</p>
<!-- @@@contains -->
<!-- $$$count[overload1]$$$count -->
<h3 class="fn"><a name="count"></a><span class="type">int</span> QDeclarativePropertyMap::<span class="name">count</span> () const</h3>
<p>This is an overloaded function.</p>
<p>Same as <a href="qdeclarativepropertymap.html#size">size</a>().</p>
<!-- @@@count -->
<!-- $$$insert[overload1]$$$insertconstQString&constQVariant& -->
<h3 class="fn"><a name="insert"></a><span class="type">void</span> QDeclarativePropertyMap::<span class="name">insert</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i>, const <span class="type"><a href="qvariant.html">QVariant</a></span> & <i>value</i> )</h3>
<p>Sets the value associated with <i>key</i> to <i>value</i>.</p>
<p>If the key doesn't exist, it is automatically created.</p>
<!-- @@@insert -->
<!-- $$$isEmpty[overload1]$$$isEmpty -->
<h3 class="fn"><a name="isEmpty"></a><span class="type">bool</span> QDeclarativePropertyMap::<span class="name">isEmpty</span> () const</h3>
<p>Returns true if the map contains no keys; otherwise returns false.</p>
<p><b>See also </b><a href="qdeclarativepropertymap.html#size">size</a>().</p>
<!-- @@@isEmpty -->
<!-- $$$keys[overload1]$$$keys -->
<h3 class="fn"><a name="keys"></a><span class="type"><a href="qstringlist.html">QStringList</a></span> QDeclarativePropertyMap::<span class="name">keys</span> () const</h3>
<p>Returns the list of keys.</p>
<p>Keys that have been cleared will still appear in this list, even though their associated values are invalid <a href="qtwebkit-bridge.html#qvariants">QVariants</a>.</p>
<!-- @@@keys -->
<!-- $$$size[overload1]$$$size -->
<h3 class="fn"><a name="size"></a><span class="type">int</span> QDeclarativePropertyMap::<span class="name">size</span> () const</h3>
<p>Returns the number of keys in the map.</p>
<p><b>See also </b><a href="qdeclarativepropertymap.html#isEmpty">isEmpty</a>() and <a href="qdeclarativepropertymap.html#count">count</a>().</p>
<!-- @@@size -->
<!-- $$$value[overload1]$$$valueconstQString& -->
<h3 class="fn"><a name="value"></a><span class="type"><a href="qvariant.html">QVariant</a></span> QDeclarativePropertyMap::<span class="name">value</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i> ) const</h3>
<p>Returns the value associated with <i>key</i>.</p>
<p>If no value has been set for this key (or if the value has been cleared), an invalid <a href="qvariant.html">QVariant</a> is returned.</p>
<!-- @@@value -->
<!-- $$$valueChanged[overload1]$$$valueChangedconstQString&constQVariant& -->
<h3 class="fn"><a name="valueChanged"></a><span class="type">void</span> QDeclarativePropertyMap::<span class="name">valueChanged</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i>, const <span class="type"><a href="qvariant.html">QVariant</a></span> & <i>value</i> )<tt> [signal]</tt></h3>
<p>This signal is emitted whenever one of the values in the map is changed. <i>key</i> is the key corresponding to the <i>value</i> that was changed.</p>
<p><b>Note:</b> valueChanged() is <b>NOT</b> emitted when changes are made by calling <a href="qdeclarativepropertymap.html#insert">insert</a>() or <a href="qdeclarativepropertymap.html#clear">clear</a>() - it is only emitted when a value is updated from QML.</p>
<!-- @@@valueChanged -->
<!-- $$$operator[][overload1]$$$operator[]constQString& -->
<h3 class="fn"><a name="operator-5b-5d"></a><span class="type"><a href="qvariant.html">QVariant</a></span> & QDeclarativePropertyMap::<span class="name">operator[]</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i> )</h3>
<p>Returns the value associated with the key <i>key</i> as a modifiable reference.</p>
<p>If the map contains no item with key <i>key</i>, the function inserts an invalid <a href="qvariant.html">QVariant</a> into the map with key <i>key</i>, and returns a reference to it.</p>
<p><b>See also </b><a href="qdeclarativepropertymap.html#insert">insert</a>() and <a href="qdeclarativepropertymap.html#value">value</a>().</p>
<!-- @@@operator[] -->
<!-- $$$operator[]$$$operator[]constQString& -->
<h3 class="fn"><a name="operator-5b-5d-2"></a><span class="type"><a href="qvariant.html">QVariant</a></span> QDeclarativePropertyMap::<span class="name">operator[]</span> ( const <span class="type"><a href="qstring.html">QString</a></span> & <i>key</i> ) const</h3>
<p>This is an overloaded function.</p>
<p>Same as <a href="qdeclarativepropertymap.html#value">value</a>().</p>
<!-- @@@operator[] -->
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