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Breadcrumbs go here --> <li><a href="modules.html">Modules</a></li> <li><a href="qtdeclarative.html">QtDeclarative</a></li> <li>QDeclarativeListProperty</li> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <div class="toc"> <h3><a name="toc">Contents</a></h3> <ul> <li class="level1"><a href="#public-types">Public Types</a></li> <li class="level1"><a href="#public-functions">Public Functions</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <h1 class="title">QDeclarativeListProperty Class Reference</h1> <!-- $$$QDeclarativeListProperty-brief --> <p>The QDeclarativeListProperty class allows applications to expose list-like properties to QML. <a href="#details">More...</a></p> <!-- @@@QDeclarativeListProperty --> <pre class="cpp"> <span class="preprocessor">#include <QDeclarativeListProperty></span></pre><p>This class was introduced in Qt 4.7.</p> <ul> <li><a href="qdeclarativelistproperty-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="qdeclarativelistproperty.html#AppendFunction-typedef">AppendFunction</a></b></td></tr> <tr><td class="memItemLeft rightAlign topAlign"> typedef </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativelistproperty.html#AtFunction-typedef">AtFunction</a></b></td></tr> <tr><td class="memItemLeft rightAlign topAlign"> typedef </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativelistproperty.html#ClearFunction-typedef">ClearFunction</a></b></td></tr> <tr><td class="memItemLeft rightAlign topAlign"> typedef </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativelistproperty.html#CountFunction-typedef">CountFunction</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="qdeclarativelistproperty.html#QDeclarativeListProperty">QDeclarativeListProperty</a></b> ( QObject * <i>object</i>, QList<T *> & <i>list</i> )</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativelistproperty.html#QDeclarativeListProperty-3">QDeclarativeListProperty</a></b> ( QObject * <i>object</i>, void * <i>data</i>, AppendFunction <i>append</i>, CountFunction <i>count</i> = 0, AtFunction <i>at</i> = 0, ClearFunction <i>clear</i> = 0 )</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qdeclarativelistproperty.html#operator-eq-eq">operator==</a></b> ( const QDeclarativeListProperty & <i>other</i> ) const</td></tr> </table> <a name="details"></a> <!-- $$$QDeclarativeListProperty-description --> <div class="descr"> <h2>Detailed Description</h2> <p>The QDeclarativeListProperty class allows applications to expose list-like properties to QML.</p> <p>QML has many list properties, where more than one object value can be assigned. The use of a list property from QML looks like this:</p> <pre class="cpp"> FruitBasket { fruit: <span class="operator">[</span> Apple {}<span class="operator">,</span> Orange{}<span class="operator">,</span> Banana{} <span class="operator">]</span> }</pre> <p>The QDeclarativeListProperty encapsulates a group of function pointers that represet the set of actions QML can perform on the list - adding items, retrieving items and clearing the list. In the future, additional operations may be supported. All list properties must implement the append operation, but the rest are optional.</p> <p>To provide a list property, a C++ class must implement the operation callbacks, and then return an appropriate QDeclarativeListProperty value from the property getter. List properties should have no setter. In the example above, the <a href="qobject.html#Q_PROPERTY">Q_PROPERTY</a>() declarative will look like this:</p> <pre class="cpp"> <a href="qobject.html#Q_PROPERTY">Q_PROPERTY</a>(<span class="type">QDeclarativeListProperty</span><span class="operator"><</span>Fruit<span class="operator">></span> fruit READ fruit);</pre> <p>QML list properties are typesafe - in this case <tt>Fruit</tt> is a <a href="qobject.html">QObject</a> type that <tt>Apple</tt>, <tt>Orange</tt> and <tt>Banana</tt> all derive from.</p> <p><b>Note:</b> QDeclarativeListProperty can only be used for lists of <a href="qobject.html">QObject</a>-derived object pointers.</p> </div> <p><b>See also </b><a href="qml-extending.html#object-and-list-property-types">Object and List Property Types</a>.</p> <!-- @@@QDeclarativeListProperty --> <div class="types"> <h2>Member Type Documentation</h2> <!-- $$$AppendFunction --> <h3 class="fn"><a name="AppendFunction-typedef"></a>typedef QDeclarativeListProperty::<span class="name">AppendFunction</span></h3> <p>Synonym for <tt>void (*)(QDeclarativeListProperty<T> *property, T *value)</tt>.</p> <p>Append the <i>value</i> to the list <i>property</i>.</p> <!-- @@@AppendFunction --> <!-- $$$AtFunction --> <h3 class="fn"><a name="AtFunction-typedef"></a>typedef QDeclarativeListProperty::<span class="name">AtFunction</span></h3> <p>Synonym for <tt>T *(*)(QDeclarativeListProperty<T> *property, int index)</tt>.</p> <p>Return the element at position <i>index</i> in the list <i>property</i>.</p> <!-- @@@AtFunction --> <!-- $$$ClearFunction --> <h3 class="fn"><a name="ClearFunction-typedef"></a>typedef QDeclarativeListProperty::<span class="name">ClearFunction</span></h3> <p>Synonym for <tt>void (*)(QDeclarativeListProperty<T> *property)</tt>.</p> <p>Clear the list <i>property</i>.</p> <!-- @@@ClearFunction --> <!-- $$$CountFunction --> <h3 class="fn"><a name="CountFunction-typedef"></a>typedef QDeclarativeListProperty::<span class="name">CountFunction</span></h3> <p>Synonym for <tt>int (*)(QDeclarativeListProperty<T> *property)</tt>.</p> <p>Return the number of elements in the list <i>property</i>.</p> <!-- @@@CountFunction --> </div> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QDeclarativeListProperty[overload1]$$$QDeclarativeListPropertyQObject*QList<T*>& --> <h3 class="fn"><a name="QDeclarativeListProperty"></a>QDeclarativeListProperty::<span class="name">QDeclarativeListProperty</span> ( <span class="type"><a href="qobject.html">QObject</a></span> * <i>object</i>, <span class="type"><a href="qlist.html">QList</a></span><<span class="type">T</span> *> & <i>list</i> )</h3> <p>Convenience constructor for making a <a href="qdeclarativelistproperty.html">QDeclarativeListProperty</a> value from an existing <a href="qlist.html">QList</a> <i>list</i>. The <i>list</i> reference must remain valid for as long as <i>object</i> exists. <i>object</i> must be provided.</p> <p>Generally this constructor should not be used in production code, as a writable <a href="qlist.html">QList</a> violates QML's memory management rules. However, this constructor can very useful while prototyping.</p> <!-- @@@QDeclarativeListProperty --> <!-- $$$QDeclarativeListProperty$$$QDeclarativeListPropertyQObject*void*AppendFunctionCountFunctionAtFunctionClearFunction --> <h3 class="fn"><a name="QDeclarativeListProperty-3"></a>QDeclarativeListProperty::<span class="name">QDeclarativeListProperty</span> ( <span class="type"><a href="qobject.html">QObject</a></span> * <i>object</i>, <span class="type">void</span> * <i>data</i>, <span class="type"><a href="qdeclarativelistproperty.html#AppendFunction-typedef">AppendFunction</a></span> <i>append</i>, <span class="type"><a href="qdeclarativelistproperty.html#CountFunction-typedef">CountFunction</a></span> <i>count</i> = 0, <span class="type"><a href="qdeclarativelistproperty.html#AtFunction-typedef">AtFunction</a></span> <i>at</i> = 0, <span class="type"><a href="qdeclarativelistproperty.html#ClearFunction-typedef">ClearFunction</a></span> <i>clear</i> = 0 )</h3> <p>Construct a <a href="qdeclarativelistproperty.html">QDeclarativeListProperty</a> from a set of operation functions. An opaque <i>data</i> handle may be passed which can be accessed from within the operation functions. The list property remains valid while <i>object</i> exists.</p> <p>The <i>append</i> operation is compulsory and must be provided, while the <i>count</i>, <i>at</i> and <i>clear</i> methods are optional.</p> <!-- @@@QDeclarativeListProperty --> <!-- $$$operator==[overload1]$$$operator==constQDeclarativeListProperty& --> <h3 class="fn"><a name="operator-eq-eq"></a><span class="type">bool</span> QDeclarativeListProperty::<span class="name">operator==</span> ( const <span class="type">QDeclarativeListProperty</span> & <i>other</i> ) const</h3> <p>Returns true if this <a href="qdeclarativelistproperty.html">QDeclarativeListProperty</a> is equal to <i>other</i>, otherwise false.</p> <!-- @@@operator== --> </div> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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