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<td >Qt 5.12</td><td ><a href="qtcore-index.html">Qt Core</a></td><td ><a href="qtcore-module.html">C++ Classes</a></td><td >QMetaObject</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right"><a href="qtcore-index.html">Qt 5.12.6 Reference Documentation</a></td>
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<h3><a name="toc">Contents</a></h3>
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<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="#public-variables">Public Variables</a></li>
<li class="level1"><a href="#static-public-members">Static Public Members</a></li>
<li class="level1"><a href="#macros">Macros</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">QMetaObject Class</h1>
<!-- $$$QMetaObject-brief -->
<p>The <a href="qmetaobject.html">QMetaObject</a> class contains meta-information about Qt objects. <a href="#details">More...</a></p>
<!-- @@@QMetaObject -->
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QMetaObject></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += core</td></tr></table></div><ul>
<li><a href="qmetaobject-members.html">List of all members, including inherited members</a></li>
</ul>
<a name="public-types"></a>
<h2 id="public-types">Public Types</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> class </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject-connection.html">Connection</a></b></td></tr>
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<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> QMetaClassInfo </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#classInfo">classInfo</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#classInfoCount">classInfoCount</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#classInfoOffset">classInfoOffset</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const char *</td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#className">className</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QMetaMethod </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#constructor">constructor</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#constructorCount">constructorCount</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QMetaEnum </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#enumerator">enumerator</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#enumeratorCount">enumeratorCount</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#enumeratorOffset">enumeratorOffset</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfClassInfo">indexOfClassInfo</a></b>(const char *<i>name</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfConstructor">indexOfConstructor</a></b>(const char *<i>constructor</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfEnumerator">indexOfEnumerator</a></b>(const char *<i>name</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfMethod">indexOfMethod</a></b>(const char *<i>method</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfProperty">indexOfProperty</a></b>(const char *<i>name</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfSignal">indexOfSignal</a></b>(const char *<i>signal</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#indexOfSlot">indexOfSlot</a></b>(const char *<i>slot</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#inherits">inherits</a></b>(const QMetaObject *<i>metaObject</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QMetaMethod </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#method">method</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#methodCount">methodCount</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#methodOffset">methodOffset</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QObject *</td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#newInstance">newInstance</a></b>(QGenericArgument <i>val0</i> = QGenericArgument(nullptr), QGenericArgument <i>val1</i> = QGenericArgument(), QGenericArgument <i>val2</i> = QGenericArgument(), QGenericArgument <i>val3</i> = QGenericArgument(), QGenericArgument <i>val4</i> = QGenericArgument(), QGenericArgument <i>val5</i> = QGenericArgument(), QGenericArgument <i>val6</i> = QGenericArgument(), QGenericArgument <i>val7</i> = QGenericArgument(), QGenericArgument <i>val8</i> = QGenericArgument(), QGenericArgument <i>val9</i> = QGenericArgument()) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QMetaProperty </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#property">property</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#propertyCount">propertyCount</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#propertyOffset">propertyOffset</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> const QMetaObject *</td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#superClass">superClass</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QMetaProperty </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#userProperty">userProperty</a></b>() const</td></tr>
</table></div>
<a name="public-variables"></a>
<h2 id="public-variables">Public Variables</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> struct (anonymous struct at /home/iurt/rpmbuild/BUILD/qtbase-everywhere-src-5.12.6/include/QtCore/../../src/corelib/kernel/qobjectdefs.h:575:5) </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#d-var">d</a></b></td></tr>
</table></div>
<a name="static-public-members"></a>
<h2 id="static-public-members">Static Public Members</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#checkConnectArgs">checkConnectArgs</a></b>(const char *<i>signal</i>, const char *<i>method</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#checkConnectArgs-1">checkConnectArgs</a></b>(const QMetaMethod &<i>signal</i>, const QMetaMethod &<i>method</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#connectSlotsByName">connectSlotsByName</a></b>(QObject *<i>object</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#invokeMethod">invokeMethod</a></b>(QObject *<i>obj</i>, const char *<i>member</i>, Qt::ConnectionType <i>type</i>, QGenericReturnArgument <i>ret</i>, QGenericArgument <i>val0</i> = QGenericArgument(nullptr), QGenericArgument <i>val1</i> = QGenericArgument(), QGenericArgument <i>val2</i> = QGenericArgument(), QGenericArgument <i>val3</i> = QGenericArgument(), QGenericArgument <i>val4</i> = QGenericArgument(), QGenericArgument <i>val5</i> = QGenericArgument(), QGenericArgument <i>val6</i> = QGenericArgument(), QGenericArgument <i>val7</i> = QGenericArgument(), QGenericArgument <i>val8</i> = QGenericArgument(), QGenericArgument <i>val9</i> = QGenericArgument())</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#invokeMethod-1">invokeMethod</a></b>(QObject *<i>obj</i>, const char *<i>member</i>, QGenericReturnArgument <i>ret</i>, QGenericArgument <i>val0</i> = ..., QGenericArgument <i>val1</i> = ..., QGenericArgument <i>val2</i> = ..., QGenericArgument <i>val3</i> = ..., QGenericArgument <i>val4</i> = ..., QGenericArgument <i>val5</i> = ..., QGenericArgument <i>val6</i> = ..., QGenericArgument <i>val7</i> = ..., QGenericArgument <i>val8</i> = ..., QGenericArgument <i>val9</i> = ...)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#invokeMethod-2">invokeMethod</a></b>(QObject *<i>obj</i>, const char *<i>member</i>, Qt::ConnectionType <i>type</i>, QGenericArgument <i>val0</i> = ..., QGenericArgument <i>val1</i> = ..., QGenericArgument <i>val2</i> = ..., QGenericArgument <i>val3</i> = ..., QGenericArgument <i>val4</i> = ..., QGenericArgument <i>val5</i> = ..., QGenericArgument <i>val6</i> = ..., QGenericArgument <i>val7</i> = ..., QGenericArgument <i>val8</i> = ..., QGenericArgument <i>val9</i> = ...)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#invokeMethod-3">invokeMethod</a></b>(QObject *<i>obj</i>, const char *<i>member</i>, QGenericArgument <i>val0</i> = ..., QGenericArgument <i>val1</i> = ..., QGenericArgument <i>val2</i> = ..., QGenericArgument <i>val3</i> = ..., QGenericArgument <i>val4</i> = ..., QGenericArgument <i>val5</i> = ..., QGenericArgument <i>val6</i> = ..., QGenericArgument <i>val7</i> = ..., QGenericArgument <i>val8</i> = ..., QGenericArgument <i>val9</i> = ...)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#invokeMethod-4">invokeMethod</a></b>(QObject *<i>context</i>, Functor <i>function</i>, Qt::ConnectionType <i>type</i> = Qt::AutoConnection, FunctorReturnType *<i>ret</i> = nullptr)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#invokeMethod-5">invokeMethod</a></b>(QObject *<i>context</i>, Functor <i>function</i>, FunctorReturnType *<i>ret</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QByteArray </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#normalizedSignature">normalizedSignature</a></b>(const char *<i>method</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QByteArray </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#normalizedType">normalizedType</a></b>(const char *<i>type</i>)</td></tr>
</table></div>
<a name="macros"></a>
<h2 id="macros">Macros</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> QGenericArgument </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#Q_ARG">Q_ARG</a></b>(<i>Type</i>, const Type &<i>value</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QGenericReturnArgument </td><td class="memItemRight bottomAlign"><b><a href="qmetaobject.html#Q_RETURN_ARG">Q_RETURN_ARG</a></b>(<i>Type</i>, Type &<i>value</i>)</td></tr>
</table></div>
<a name="details"></a>
<!-- $$$QMetaObject-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qmetaobject.html">QMetaObject</a> class contains meta-information about Qt objects.</p>
<p>The Qt <a href="metaobjects.html">Meta-Object System</a> in Qt is responsible for the signals and slots inter-object communication mechanism, runtime type information, and the Qt property system. A single <a href="qmetaobject.html">QMetaObject</a> instance is created for each <a href="qobject.html">QObject</a> subclass that is used in an application, and this instance stores all the meta-information for the <a href="qobject.html">QObject</a> subclass. This object is available as <a href="qobject.html#metaObject">QObject::metaObject</a>().</p>
<p>This class is not normally required for application programming, but it is useful if you write meta-applications, such as scripting engines or GUI builders.</p>
<p>The functions you are most likely to find useful are these:</p>
<ul>
<li><a href="qmetaobject.html#className">className</a>() returns the name of a class.</li>
<li><a href="qmetaobject.html#superClass">superClass</a>() returns the superclass's meta-object.</li>
<li><a href="qmetaobject.html#method">method</a>() and <a href="qmetaobject.html#methodCount">methodCount</a>() provide information about a class's meta-methods (signals, slots and other <a href="qobject.html#Q_INVOKABLE">invokable</a> member functions).</li>
<li><a href="qmetaobject.html#enumerator">enumerator</a>() and <a href="qmetaobject.html#enumeratorCount">enumeratorCount</a>() and provide information about a class's enumerators.</li>
<li><a href="qmetaobject.html#propertyCount">propertyCount</a>() and <a href="qmetaobject.html#property">property</a>() provide information about a class's properties.</li>
<li><a href="qmetaobject.html#constructor">constructor</a>() and <a href="qmetaobject.html#constructorCount">constructorCount</a>() provide information about a class's meta-constructors.</li>
</ul>
<p>The index functions <a href="qmetaobject.html#indexOfConstructor">indexOfConstructor</a>(), <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>(), <a href="qmetaobject.html#indexOfEnumerator">indexOfEnumerator</a>(), and <a href="qmetaobject.html#indexOfProperty">indexOfProperty</a>() map names of constructors, member functions, enumerators, or properties to indexes in the meta-object. For example, Qt uses <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>() internally when you connect a signal to a slot.</p>
<p>Classes can also have a list of <i>name</i>--<i>value</i> pairs of additional class information, stored in <a href="qmetaclassinfo.html">QMetaClassInfo</a> objects. The number of pairs is returned by <a href="qmetaobject.html#classInfoCount">classInfoCount</a>(), single pairs are returned by <a href="qmetaobject.html#classInfo">classInfo</a>(), and you can search for pairs with <a href="qmetaobject.html#indexOfClassInfo">indexOfClassInfo</a>().</p>
<p><b>Note: </b>Operations that use the meta object system are generally thread- safe, as QMetaObjects are typically static read-only instances generated at compile time. However, if meta objects are dynamically modified by the application (for instance, when using QQmlPropertyMap), then the application has to explicitly synchronize access to the respective meta object.</p></div>
<p><b>See also </b><a href="qmetaclassinfo.html">QMetaClassInfo</a>, <a href="qmetaenum.html">QMetaEnum</a>, <a href="qmetamethod.html">QMetaMethod</a>, <a href="qmetaproperty.html">QMetaProperty</a>, <a href="qmetatype.html">QMetaType</a>, and <a href="metaobjects.html">Meta-Object System</a>.</p>
<!-- @@@QMetaObject -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$checkConnectArgs[overload1]$$$checkConnectArgsconstchar*constchar* -->
<h3 class="fn" id="checkConnectArgs"><a name="checkConnectArgs"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">checkConnectArgs</span>(const <span class="type">char</span> *<i>signal</i>, const <span class="type">char</span> *<i>method</i>)</h3>
<p>Returns <code>true</code> if the <i>signal</i> and <i>method</i> arguments are compatible; otherwise returns <code>false</code>.</p>
<p>Both <i>signal</i> and <i>method</i> are expected to be normalized.</p>
<p><b>See also </b><a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<!-- @@@checkConnectArgs -->
<!-- $$$checkConnectArgs$$$checkConnectArgsconstQMetaMethod&constQMetaMethod& -->
<h3 class="fn" id="checkConnectArgs-1"><a name="checkConnectArgs-1"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">checkConnectArgs</span>(const <span class="type"><a href="qmetamethod.html">QMetaMethod</a></span> &<i>signal</i>, const <span class="type"><a href="qmetamethod.html">QMetaMethod</a></span> &<i>method</i>)</h3>
<p>This is an overloaded function.</p>
<p>Returns <code>true</code> if the <i>signal</i> and <i>method</i> arguments are compatible; otherwise returns <code>false</code>.</p>
<p>This function was introduced in Qt 5.0.</p>
<!-- @@@checkConnectArgs -->
<!-- $$$classInfo[overload1]$$$classInfoint -->
<h3 class="fn" id="classInfo"><a name="classInfo"></a><span class="type"><a href="qmetaclassinfo.html">QMetaClassInfo</a></span> QMetaObject::<span class="name">classInfo</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the meta-data for the item of class information with the given <i>index</i>.</p>
<p>Example:</p>
<pre class="cpp">
<span class="keyword">class</span> MyClass : <span class="keyword">public</span> <span class="type"><a href="qobject.html">QObject</a></span>
{
Q_OBJECT
Q_CLASSINFO(<span class="string">"author"</span><span class="operator">,</span> <span class="string">"Sabrina Schweinsteiger"</span>)
Q_CLASSINFO(<span class="string">"url"</span><span class="operator">,</span> <span class="string">"http://doc.moosesoft.co.uk/1.0/"</span>)
<span class="keyword">public</span>:
<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>
};
</pre>
<p><b>See also </b><a href="qmetaobject.html#classInfoCount">classInfoCount</a>(), <a href="qmetaobject.html#classInfoOffset">classInfoOffset</a>(), and <a href="qmetaobject.html#indexOfClassInfo">indexOfClassInfo</a>().</p>
<!-- @@@classInfo -->
<!-- $$$classInfoCount[overload1]$$$classInfoCount -->
<h3 class="fn" id="classInfoCount"><a name="classInfoCount"></a><span class="type">int</span> QMetaObject::<span class="name">classInfoCount</span>() const</h3>
<p>Returns the number of items of class information in this class.</p>
<p><b>See also </b><a href="qmetaobject.html#classInfo">classInfo</a>(), <a href="qmetaobject.html#classInfoOffset">classInfoOffset</a>(), and <a href="qmetaobject.html#indexOfClassInfo">indexOfClassInfo</a>().</p>
<!-- @@@classInfoCount -->
<!-- $$$classInfoOffset[overload1]$$$classInfoOffset -->
<h3 class="fn" id="classInfoOffset"><a name="classInfoOffset"></a><span class="type">int</span> QMetaObject::<span class="name">classInfoOffset</span>() const</h3>
<p>Returns the class information offset for this class; i.e. the index position of this class's first class information item.</p>
<p>If the class has no superclasses with class information, the offset is 0; otherwise the offset is the sum of all the class information items in the class's superclasses.</p>
<p><b>See also </b><a href="qmetaobject.html#classInfo">classInfo</a>(), <a href="qmetaobject.html#classInfoCount">classInfoCount</a>(), and <a href="qmetaobject.html#indexOfClassInfo">indexOfClassInfo</a>().</p>
<!-- @@@classInfoOffset -->
<!-- $$$className[overload1]$$$className -->
<h3 class="fn" id="className"><a name="className"></a>const <span class="type">char</span> *QMetaObject::<span class="name">className</span>() const</h3>
<p>Returns the class name.</p>
<p><b>See also </b><a href="qmetaobject.html#superClass">superClass</a>().</p>
<!-- @@@className -->
<!-- $$$connectSlotsByName[overload1]$$$connectSlotsByNameQObject* -->
<h3 class="fn" id="connectSlotsByName"><a name="connectSlotsByName"></a><code>[static] </code><span class="type">void</span> QMetaObject::<span class="name">connectSlotsByName</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>object</i>)</h3>
<p>Searches recursively for all child objects of the given <i>object</i>, and connects matching signals from them to slots of <i>object</i> that follow the following form:</p>
<pre class="cpp">
<span class="type">void</span> on_<span class="operator"><</span>object name<span class="operator">></span>_<span class="operator"><</span>signal name<span class="operator">></span>(<span class="operator"><</span>signal parameters<span class="operator">></span>);
</pre>
<p>Let's assume our object has a child object of type <code>QPushButton</code> with the <a href="qobject.html#objectName-prop">object name</a> <code>button1</code>. The slot to catch the button's <code>clicked()</code> signal would be:</p>
<pre class="cpp">
<span class="type">void</span> on_button1_clicked();
</pre>
<p>If <i>object</i> itself has a properly set object name, its own signals are also connected to its respective slots.</p>
<p><b>See also </b><a href="qobject.html#objectName-prop">QObject::setObjectName</a>().</p>
<!-- @@@connectSlotsByName -->
<!-- $$$constructor[overload1]$$$constructorint -->
<h3 class="fn" id="constructor"><a name="constructor"></a><span class="type"><a href="qmetamethod.html">QMetaMethod</a></span> QMetaObject::<span class="name">constructor</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the meta-data for the constructor with the given <i>index</i>.</p>
<p>This function was introduced in Qt 4.5.</p>
<p><b>See also </b><a href="qmetaobject.html#constructorCount">constructorCount</a>() and <a href="qmetaobject.html#newInstance">newInstance</a>().</p>
<!-- @@@constructor -->
<!-- $$$constructorCount[overload1]$$$constructorCount -->
<h3 class="fn" id="constructorCount"><a name="constructorCount"></a><span class="type">int</span> QMetaObject::<span class="name">constructorCount</span>() const</h3>
<p>Returns the number of constructors in this class.</p>
<p>This function was introduced in Qt 4.5.</p>
<p><b>See also </b><a href="qmetaobject.html#constructor">constructor</a>() and <a href="qmetaobject.html#indexOfConstructor">indexOfConstructor</a>().</p>
<!-- @@@constructorCount -->
<!-- $$$enumerator[overload1]$$$enumeratorint -->
<h3 class="fn" id="enumerator"><a name="enumerator"></a><span class="type"><a href="qmetaenum.html">QMetaEnum</a></span> QMetaObject::<span class="name">enumerator</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the meta-data for the enumerator with the given <i>index</i>.</p>
<p><b>See also </b><a href="qmetaobject.html#enumeratorCount">enumeratorCount</a>(), <a href="qmetaobject.html#enumeratorOffset">enumeratorOffset</a>(), and <a href="qmetaobject.html#indexOfEnumerator">indexOfEnumerator</a>().</p>
<!-- @@@enumerator -->
<!-- $$$enumeratorCount[overload1]$$$enumeratorCount -->
<h3 class="fn" id="enumeratorCount"><a name="enumeratorCount"></a><span class="type">int</span> QMetaObject::<span class="name">enumeratorCount</span>() const</h3>
<p>Returns the number of enumerators in this class.</p>
<p><b>See also </b><a href="qmetaobject.html#enumerator">enumerator</a>(), <a href="qmetaobject.html#enumeratorOffset">enumeratorOffset</a>(), and <a href="qmetaobject.html#indexOfEnumerator">indexOfEnumerator</a>().</p>
<!-- @@@enumeratorCount -->
<!-- $$$enumeratorOffset[overload1]$$$enumeratorOffset -->
<h3 class="fn" id="enumeratorOffset"><a name="enumeratorOffset"></a><span class="type">int</span> QMetaObject::<span class="name">enumeratorOffset</span>() const</h3>
<p>Returns the enumerator offset for this class; i.e. the index position of this class's first enumerator.</p>
<p>If the class has no superclasses with enumerators, the offset is 0; otherwise the offset is the sum of all the enumerators in the class's superclasses.</p>
<p><b>See also </b><a href="qmetaobject.html#enumerator">enumerator</a>(), <a href="qmetaobject.html#enumeratorCount">enumeratorCount</a>(), and <a href="qmetaobject.html#indexOfEnumerator">indexOfEnumerator</a>().</p>
<!-- @@@enumeratorOffset -->
<!-- $$$indexOfClassInfo[overload1]$$$indexOfClassInfoconstchar* -->
<h3 class="fn" id="indexOfClassInfo"><a name="indexOfClassInfo"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfClassInfo</span>(const <span class="type">char</span> *<i>name</i>) const</h3>
<p>Finds class information item <i>name</i> and returns its index; otherwise returns -1.</p>
<p><b>See also </b><a href="qmetaobject.html#classInfo">classInfo</a>(), <a href="qmetaobject.html#classInfoCount">classInfoCount</a>(), and <a href="qmetaobject.html#classInfoOffset">classInfoOffset</a>().</p>
<!-- @@@indexOfClassInfo -->
<!-- $$$indexOfConstructor[overload1]$$$indexOfConstructorconstchar* -->
<h3 class="fn" id="indexOfConstructor"><a name="indexOfConstructor"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfConstructor</span>(const <span class="type">char</span> *<i>constructor</i>) const</h3>
<p>Finds <i>constructor</i> and returns its index; otherwise returns -1.</p>
<p>Note that the <i>constructor</i> has to be in normalized form, as returned by <a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<p>This function was introduced in Qt 4.5.</p>
<p><b>See also </b><a href="qmetaobject.html#constructor">constructor</a>(), <a href="qmetaobject.html#constructorCount">constructorCount</a>(), and <a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<!-- @@@indexOfConstructor -->
<!-- $$$indexOfEnumerator[overload1]$$$indexOfEnumeratorconstchar* -->
<h3 class="fn" id="indexOfEnumerator"><a name="indexOfEnumerator"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfEnumerator</span>(const <span class="type">char</span> *<i>name</i>) const</h3>
<p>Finds enumerator <i>name</i> and returns its index; otherwise returns -1.</p>
<p><b>See also </b><a href="qmetaobject.html#enumerator">enumerator</a>(), <a href="qmetaobject.html#enumeratorCount">enumeratorCount</a>(), and <a href="qmetaobject.html#enumeratorOffset">enumeratorOffset</a>().</p>
<!-- @@@indexOfEnumerator -->
<!-- $$$indexOfMethod[overload1]$$$indexOfMethodconstchar* -->
<h3 class="fn" id="indexOfMethod"><a name="indexOfMethod"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfMethod</span>(const <span class="type">char</span> *<i>method</i>) const</h3>
<p>Finds <i>method</i> and returns its index; otherwise returns -1.</p>
<p>Note that the <i>method</i> has to be in normalized form, as returned by <a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<p><b>See also </b><a href="qmetaobject.html#method">method</a>(), <a href="qmetaobject.html#methodCount">methodCount</a>(), <a href="qmetaobject.html#methodOffset">methodOffset</a>(), and <a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<!-- @@@indexOfMethod -->
<!-- $$$indexOfProperty[overload1]$$$indexOfPropertyconstchar* -->
<h3 class="fn" id="indexOfProperty"><a name="indexOfProperty"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfProperty</span>(const <span class="type">char</span> *<i>name</i>) const</h3>
<p>Finds property <i>name</i> and returns its index; otherwise returns -1.</p>
<p><b>See also </b><a href="qmetaobject.html#property">property</a>(), <a href="qmetaobject.html#propertyCount">propertyCount</a>(), and <a href="qmetaobject.html#propertyOffset">propertyOffset</a>().</p>
<!-- @@@indexOfProperty -->
<!-- $$$indexOfSignal[overload1]$$$indexOfSignalconstchar* -->
<h3 class="fn" id="indexOfSignal"><a name="indexOfSignal"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfSignal</span>(const <span class="type">char</span> *<i>signal</i>) const</h3>
<p>Finds <i>signal</i> and returns its index; otherwise returns -1.</p>
<p>This is the same as <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>(), except that it will return -1 if the method exists but isn't a signal.</p>
<p>Note that the <i>signal</i> has to be in normalized form, as returned by <a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<p><b>See also </b><a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>(), <a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>(), <a href="qmetaobject.html#method">method</a>(), <a href="qmetaobject.html#methodCount">methodCount</a>(), and <a href="qmetaobject.html#methodOffset">methodOffset</a>().</p>
<!-- @@@indexOfSignal -->
<!-- $$$indexOfSlot[overload1]$$$indexOfSlotconstchar* -->
<h3 class="fn" id="indexOfSlot"><a name="indexOfSlot"></a><span class="type">int</span> QMetaObject::<span class="name">indexOfSlot</span>(const <span class="type">char</span> *<i>slot</i>) const</h3>
<p>Finds <i>slot</i> and returns its index; otherwise returns -1.</p>
<p>This is the same as <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>(), except that it will return -1 if the method exists but isn't a slot.</p>
<p><b>See also </b><a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>(), <a href="qmetaobject.html#method">method</a>(), <a href="qmetaobject.html#methodCount">methodCount</a>(), and <a href="qmetaobject.html#methodOffset">methodOffset</a>().</p>
<!-- @@@indexOfSlot -->
<!-- $$$inherits[overload1]$$$inheritsconstQMetaObject* -->
<h3 class="fn" id="inherits"><a name="inherits"></a><span class="type">bool</span> QMetaObject::<span class="name">inherits</span>(const <span class="type"><a href="qmetaobject.html">QMetaObject</a></span> *<i>metaObject</i>) const</h3>
<p>Returns <code>true</code> if the class described by this <a href="qmetaobject.html">QMetaObject</a> inherits the type described by <i>metaObject</i>; otherwise returns false.</p>
<p>A type is considered to inherit itself.</p>
<p>This function was introduced in Qt 5.7.</p>
<!-- @@@inherits -->
<!-- $$$invokeMethod[overload1]$$$invokeMethodQObject*constchar*Qt::ConnectionTypeQGenericReturnArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgument -->
<h3 class="fn" id="invokeMethod"><a name="invokeMethod"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">invokeMethod</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>obj</i>, const <span class="type">char</span> *<i>member</i>, <span class="type"><a href="qt.html#ConnectionType-enum">Qt::ConnectionType</a></span> <i>type</i>, <span class="type"><a href="qgenericreturnargument.html">QGenericReturnArgument</a></span> <i>ret</i>, <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val0</i> = QGenericArgument(nullptr), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val1</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val2</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val3</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val4</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val5</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val6</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val7</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val8</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val9</i> = QGenericArgument())</h3>
<p>Invokes the <i>member</i> (a signal or a slot name) on the object <i>obj</i>. Returns <code>true</code> if the member could be invoked. Returns <code>false</code> if there is no such member or the parameters did not match.</p>
<p>The invocation can be either synchronous or asynchronous, depending on <i>type</i>:</p>
<ul>
<li>If <i>type</i> is <a href="qt.html#ConnectionType-enum">Qt::DirectConnection</a>, the member will be invoked immediately.</li>
<li>If <i>type</i> is <a href="qt.html#ConnectionType-enum">Qt::QueuedConnection</a>, a <a href="qevent.html">QEvent</a> will be sent and the member is invoked as soon as the application enters the main event loop.</li>
<li>If <i>type</i> is <a href="qt.html#ConnectionType-enum">Qt::BlockingQueuedConnection</a>, the method will be invoked in the same way as for <a href="qt.html#ConnectionType-enum">Qt::QueuedConnection</a>, except that the current thread will block until the event is delivered. Using this connection type to communicate between objects in the same thread will lead to deadlocks.</li>
<li>If <i>type</i> is <a href="qt.html#ConnectionType-enum">Qt::AutoConnection</a>, the member is invoked synchronously if <i>obj</i> lives in the same thread as the caller; otherwise it will invoke the member asynchronously.</li>
</ul>
<p>The return value of the <i>member</i> function call is placed in <i>ret</i>. If the invocation is asynchronous, the return value cannot be evaluated. You can pass up to ten arguments (<i>val0</i>, <i>val1</i>, <i>val2</i>, <i>val3</i>, <i>val4</i>, <i>val5</i>, <i>val6</i>, <i>val7</i>, <i>val8</i>, and <i>val9</i>) to the <i>member</i> function.</p>
<p><a href="qgenericargument.html">QGenericArgument</a> and <a href="qgenericreturnargument.html">QGenericReturnArgument</a> are internal helper classes. Because signals and slots can be dynamically invoked, you must enclose the arguments using the <a href="qmetaobject.html#Q_ARG">Q_ARG</a>() and <a href="qmetaobject.html#Q_RETURN_ARG">Q_RETURN_ARG</a>() macros. <a href="qmetaobject.html#Q_ARG">Q_ARG</a>() takes a type name and a const reference of that type; <a href="qmetaobject.html#Q_RETURN_ARG">Q_RETURN_ARG</a>() takes a type name and a non-const reference.</p>
<p>You only need to pass the name of the signal or slot to this function, not the entire signature. For example, to asynchronously invoke the <a href="qthread.html#quit">quit()</a> slot on a <a href="qthread.html">QThread</a>, use the following code:</p>
<pre class="cpp">
<span class="type"><a href="qmetaobject.html">QMetaObject</a></span><span class="operator">::</span>invokeMethod(thread<span class="operator">,</span> <span class="string">"quit"</span><span class="operator">,</span>
<span class="type">Qt</span><span class="operator">::</span>QueuedConnection);
</pre>
<p>With asynchronous method invocations, the parameters must be of types that are known to Qt's meta-object system, because Qt needs to copy the arguments to store them in an event behind the scenes. If you try to use a queued connection and get the error message</p>
<pre class="cpp">
<span class="type"><a href="qmetaobject.html">QMetaObject</a></span><span class="operator">::</span>invokeMethod: Unable to handle unregistered datatype <span class="char">'MyType'</span>
</pre>
<p>call <a href="qmetatype.html#qRegisterMetaType-1">qRegisterMetaType</a>() to register the data type before you call invokeMethod().</p>
<p>To synchronously invoke the <code>compute(QString, int, double)</code> slot on some arbitrary object <code>obj</code> retrieve its return value:</p>
<pre class="cpp">
<span class="type"><a href="qstring.html">QString</a></span> retVal;
<span class="type"><a href="qmetaobject.html">QMetaObject</a></span><span class="operator">::</span>invokeMethod(obj<span class="operator">,</span> <span class="string">"compute"</span><span class="operator">,</span> <span class="type">Qt</span><span class="operator">::</span>DirectConnection<span class="operator">,</span>
Q_RETURN_ARG(<span class="type"><a href="qstring.html">QString</a></span><span class="operator">,</span> retVal)<span class="operator">,</span>
Q_ARG(<span class="type"><a href="qstring.html">QString</a></span><span class="operator">,</span> <span class="string">"sqrt"</span>)<span class="operator">,</span>
Q_ARG(<span class="type">int</span><span class="operator">,</span> <span class="number">42</span>)<span class="operator">,</span>
Q_ARG(<span class="type">double</span><span class="operator">,</span> <span class="number">9.7</span>));
</pre>
<p>If the "compute" slot does not take exactly one <a href="qstring.html">QString</a>, one int and one double in the specified order, the call will fail.</p>
<p><b>Note:</b> This function is thread-safe.</p>
<p><b>See also </b><a href="qmetaobject.html#Q_ARG">Q_ARG</a>(), <a href="qmetaobject.html#Q_RETURN_ARG">Q_RETURN_ARG</a>(), <a href="qmetatype.html#qRegisterMetaType-1">qRegisterMetaType</a>(), and <a href="qmetamethod.html#invoke">QMetaMethod::invoke</a>().</p>
<!-- @@@invokeMethod -->
<!-- $$$invokeMethod$$$invokeMethodQObject*constchar*QGenericReturnArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgument -->
<h3 class="fn" id="invokeMethod-1"><a name="invokeMethod-1"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">invokeMethod</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>obj</i>, const <span class="type">char</span> *<i>member</i>, <span class="type"><a href="qgenericreturnargument.html">QGenericReturnArgument</a></span> <i>ret</i>, <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val0</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val1</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val2</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val3</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val4</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val5</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val6</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val7</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val8</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val9</i> = ...)</h3>
<p>This function overloads <a href="qmetaobject.html#invokeMethod">invokeMethod</a>().</p>
<p>This overload always invokes the member using the connection type <a href="qt.html#ConnectionType-enum">Qt::AutoConnection</a>.</p>
<p><b>Note:</b> This function is thread-safe.</p>
<!-- @@@invokeMethod -->
<!-- $$$invokeMethod$$$invokeMethodQObject*constchar*Qt::ConnectionTypeQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgument -->
<h3 class="fn" id="invokeMethod-2"><a name="invokeMethod-2"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">invokeMethod</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>obj</i>, const <span class="type">char</span> *<i>member</i>, <span class="type"><a href="qt.html#ConnectionType-enum">Qt::ConnectionType</a></span> <i>type</i>, <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val0</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val1</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val2</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val3</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val4</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val5</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val6</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val7</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val8</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val9</i> = ...)</h3>
<p>This function overloads <a href="qmetaobject.html#invokeMethod">invokeMethod</a>().</p>
<p>This overload can be used if the return value of the member is of no interest.</p>
<p><b>Note:</b> This function is thread-safe.</p>
<!-- @@@invokeMethod -->
<!-- $$$invokeMethod$$$invokeMethodQObject*constchar*QGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgument -->
<h3 class="fn" id="invokeMethod-3"><a name="invokeMethod-3"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">invokeMethod</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>obj</i>, const <span class="type">char</span> *<i>member</i>, <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val0</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val1</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val2</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val3</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val4</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val5</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val6</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val7</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val8</i> = ..., <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val9</i> = ...)</h3>
<p>This function overloads <a href="qmetaobject.html#invokeMethod">invokeMethod</a>().</p>
<p>This overload invokes the member using the connection type <a href="qt.html#ConnectionType-enum">Qt::AutoConnection</a> and ignores return values.</p>
<p><b>Note:</b> This function is thread-safe.</p>
<!-- @@@invokeMethod -->
<!-- $$$invokeMethod$$$invokeMethodQObject*FunctorQt::ConnectionTypeFunctorReturnType* -->
<h3 class="fn" id="invokeMethod-4"><a name="invokeMethod-4"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">invokeMethod</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>context</i>, <span class="type">Functor</span> <i>function</i>, <span class="type"><a href="qt.html#ConnectionType-enum">Qt::ConnectionType</a></span> <i>type</i> = Qt::AutoConnection, <span class="type">FunctorReturnType</span> *<i>ret</i> = nullptr)</h3>
<p>This is an overloaded function.</p>
<p>Invokes the <i>function</i> in the event loop of <i>context</i>. <i>function</i> can be a functor or a pointer to a member function. Returns <code>true</code> if the function could be invoked. Returns <code>false</code> if there is no such function or the parameters did not match. The return value of the function call is placed in <i>ret</i>.</p>
<p><b>Note:</b> This function is thread-safe.</p>
<p>This function was introduced in Qt 5.10.</p>
<!-- @@@invokeMethod -->
<!-- $$$invokeMethod$$$invokeMethodQObject*FunctorFunctorReturnType* -->
<h3 class="fn" id="invokeMethod-5"><a name="invokeMethod-5"></a><code>[static] </code><span class="type">bool</span> QMetaObject::<span class="name">invokeMethod</span>(<span class="type"><a href="qobject.html">QObject</a></span> *<i>context</i>, <span class="type">Functor</span> <i>function</i>, <span class="type">FunctorReturnType</span> *<i>ret</i>)</h3>
<p>This is an overloaded function.</p>
<p>Invokes the <i>function</i> in the event loop of <i>context</i> using the connection type <a href="qt.html#ConnectionType-enum">Qt::AutoConnection</a>. <i>function</i> can be a functor or a pointer to a member function. Returns <code>true</code> if the function could be invoked. Returns <code>false</code> if there is no such member or the parameters did not match. The return value of the function call is placed in <i>ret</i>.</p>
<p><b>Note:</b> This function is thread-safe.</p>
<p>This function was introduced in Qt 5.10.</p>
<!-- @@@invokeMethod -->
<!-- $$$method[overload1]$$$methodint -->
<h3 class="fn" id="method"><a name="method"></a><span class="type"><a href="qmetamethod.html">QMetaMethod</a></span> QMetaObject::<span class="name">method</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the meta-data for the method with the given <i>index</i>.</p>
<p><b>See also </b><a href="qmetaobject.html#methodCount">methodCount</a>(), <a href="qmetaobject.html#methodOffset">methodOffset</a>(), and <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>().</p>
<!-- @@@method -->
<!-- $$$methodCount[overload1]$$$methodCount -->
<h3 class="fn" id="methodCount"><a name="methodCount"></a><span class="type">int</span> QMetaObject::<span class="name">methodCount</span>() const</h3>
<p>Returns the number of methods in this class, including the number of methods provided by each base class. These include signals and slots as well as normal member functions.</p>
<p>Use code like the following to obtain a <a href="qstringlist.html">QStringList</a> containing the methods specific to a given class:</p>
<pre class="cpp">
<span class="keyword">const</span> <span class="type"><a href="qmetaobject.html">QMetaObject</a></span><span class="operator">*</span> metaObject <span class="operator">=</span> obj<span class="operator">-</span><span class="operator">></span>metaObject();
<span class="type"><a href="qstringlist.html">QStringList</a></span> methods;
<span class="keyword">for</span>(<span class="type">int</span> i <span class="operator">=</span> metaObject<span class="operator">-</span><span class="operator">></span>methodOffset(); i <span class="operator"><</span> metaObject<span class="operator">-</span><span class="operator">></span>methodCount(); <span class="operator">+</span><span class="operator">+</span>i)
methods <span class="operator"><</span><span class="operator"><</span> <span class="type"><a href="qstring.html">QString</a></span><span class="operator">::</span>fromLatin1(metaObject<span class="operator">-</span><span class="operator">></span>method(i)<span class="operator">.</span>methodSignature());
</pre>
<p><b>See also </b><a href="qmetaobject.html#method">method</a>(), <a href="qmetaobject.html#methodOffset">methodOffset</a>(), and <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>().</p>
<!-- @@@methodCount -->
<!-- $$$methodOffset[overload1]$$$methodOffset -->
<h3 class="fn" id="methodOffset"><a name="methodOffset"></a><span class="type">int</span> QMetaObject::<span class="name">methodOffset</span>() const</h3>
<p>Returns the method offset for this class; i.e. the index position of this class's first member function.</p>
<p>The offset is the sum of all the methods in the class's superclasses (which is always positive since <a href="qobject.html">QObject</a> has the deleteLater() slot and a destroyed() signal).</p>
<p><b>See also </b><a href="qmetaobject.html#method">method</a>(), <a href="qmetaobject.html#methodCount">methodCount</a>(), and <a href="qmetaobject.html#indexOfMethod">indexOfMethod</a>().</p>
<!-- @@@methodOffset -->
<!-- $$$newInstance[overload1]$$$newInstanceQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgumentQGenericArgument -->
<h3 class="fn" id="newInstance"><a name="newInstance"></a><span class="type"><a href="qobject.html">QObject</a></span> *QMetaObject::<span class="name">newInstance</span>(<span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val0</i> = QGenericArgument(nullptr), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val1</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val2</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val3</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val4</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val5</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val6</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val7</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val8</i> = QGenericArgument(), <span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <i>val9</i> = QGenericArgument()) const</h3>
<p>Constructs a new instance of this class. You can pass up to ten arguments (<i>val0</i>, <i>val1</i>, <i>val2</i>, <i>val3</i>, <i>val4</i>, <i>val5</i>, <i>val6</i>, <i>val7</i>, <i>val8</i>, and <i>val9</i>) to the constructor. Returns the new object, or 0 if no suitable constructor is available.</p>
<p>Note that only constructors that are declared with the <a href="qobject.html#Q_INVOKABLE">Q_INVOKABLE</a> modifier are made available through the meta-object system.</p>
<p>This function was introduced in Qt 4.5.</p>
<p><b>See also </b><a href="qmetaobject.html#Q_ARG">Q_ARG</a>() and <a href="qmetaobject.html#constructor">constructor</a>().</p>
<!-- @@@newInstance -->
<!-- $$$normalizedSignature[overload1]$$$normalizedSignatureconstchar* -->
<h3 class="fn" id="normalizedSignature"><a name="normalizedSignature"></a><code>[static] </code><span class="type"><a href="qbytearray.html">QByteArray</a></span> QMetaObject::<span class="name">normalizedSignature</span>(const <span class="type">char</span> *<i>method</i>)</h3>
<p>Normalizes the signature of the given <i>method</i>.</p>
<p>Qt uses normalized signatures to decide whether two given signals and slots are compatible. Normalization reduces whitespace to a minimum, moves 'const' to the front where appropriate, removes 'const' from value types and replaces const references with values.</p>
<p><b>See also </b><a href="qmetaobject.html#checkConnectArgs">checkConnectArgs</a>() and <a href="qmetaobject.html#normalizedType">normalizedType</a>().</p>
<!-- @@@normalizedSignature -->
<!-- $$$normalizedType[overload1]$$$normalizedTypeconstchar* -->
<h3 class="fn" id="normalizedType"><a name="normalizedType"></a><code>[static] </code><span class="type"><a href="qbytearray.html">QByteArray</a></span> QMetaObject::<span class="name">normalizedType</span>(const <span class="type">char</span> *<i>type</i>)</h3>
<p>Normalizes a <i>type</i>.</p>
<p>See <a href="qmetaobject.html#normalizedSignature">QMetaObject::normalizedSignature</a>() for a description on how Qt normalizes.</p>
<p>Example:</p>
<pre class="cpp">
<span class="type"><a href="qbytearray.html">QByteArray</a></span> normType <span class="operator">=</span> <span class="type"><a href="qmetaobject.html">QMetaObject</a></span><span class="operator">::</span>normalizedType(<span class="string">" int const *"</span>);
<span class="comment">// normType is now "const int*"</span>
</pre>
<p>This function was introduced in Qt 4.2.</p>
<p><b>See also </b><a href="qmetaobject.html#normalizedSignature">normalizedSignature</a>().</p>
<!-- @@@normalizedType -->
<!-- $$$property[overload1]$$$propertyint -->
<h3 class="fn" id="property"><a name="property"></a><span class="type"><a href="qmetaproperty.html">QMetaProperty</a></span> QMetaObject::<span class="name">property</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the meta-data for the property with the given <i>index</i>. If no such property exists, a null <a href="qmetaproperty.html">QMetaProperty</a> is returned.</p>
<p><b>See also </b><a href="qmetaobject.html#propertyCount">propertyCount</a>(), <a href="qmetaobject.html#propertyOffset">propertyOffset</a>(), and <a href="qmetaobject.html#indexOfProperty">indexOfProperty</a>().</p>
<!-- @@@property -->
<!-- $$$propertyCount[overload1]$$$propertyCount -->
<h3 class="fn" id="propertyCount"><a name="propertyCount"></a><span class="type">int</span> QMetaObject::<span class="name">propertyCount</span>() const</h3>
<p>Returns the number of properties in this class, including the number of properties provided by each base class.</p>
<p>Use code like the following to obtain a <a href="qstringlist.html">QStringList</a> containing the properties specific to a given class:</p>
<pre class="cpp">
<span class="keyword">const</span> <span class="type"><a href="qmetaobject.html">QMetaObject</a></span><span class="operator">*</span> metaObject <span class="operator">=</span> obj<span class="operator">-</span><span class="operator">></span>metaObject();
<span class="type"><a href="qstringlist.html">QStringList</a></span> properties;
<span class="keyword">for</span>(<span class="type">int</span> i <span class="operator">=</span> metaObject<span class="operator">-</span><span class="operator">></span>propertyOffset(); i <span class="operator"><</span> metaObject<span class="operator">-</span><span class="operator">></span>propertyCount(); <span class="operator">+</span><span class="operator">+</span>i)
properties <span class="operator"><</span><span class="operator"><</span> <span class="type"><a href="qstring.html">QString</a></span><span class="operator">::</span>fromLatin1(metaObject<span class="operator">-</span><span class="operator">></span>property(i)<span class="operator">.</span>name());
</pre>
<p><b>See also </b><a href="qmetaobject.html#property">property</a>(), <a href="qmetaobject.html#propertyOffset">propertyOffset</a>(), and <a href="qmetaobject.html#indexOfProperty">indexOfProperty</a>().</p>
<!-- @@@propertyCount -->
<!-- $$$propertyOffset[overload1]$$$propertyOffset -->
<h3 class="fn" id="propertyOffset"><a name="propertyOffset"></a><span class="type">int</span> QMetaObject::<span class="name">propertyOffset</span>() const</h3>
<p>Returns the property offset for this class; i.e. the index position of this class's first property.</p>
<p>The offset is the sum of all the properties in the class's superclasses (which is always positive since <a href="qobject.html">QObject</a> has the name() property).</p>
<p><b>See also </b><a href="qmetaobject.html#property">property</a>(), <a href="qmetaobject.html#propertyCount">propertyCount</a>(), and <a href="qmetaobject.html#indexOfProperty">indexOfProperty</a>().</p>
<!-- @@@propertyOffset -->
<!-- $$$superClass[overload1]$$$superClass -->
<h3 class="fn" id="superClass"><a name="superClass"></a>const <span class="type"><a href="qmetaobject.html">QMetaObject</a></span> *QMetaObject::<span class="name">superClass</span>() const</h3>
<p>Returns the meta-object of the superclass, or 0 if there is no such object.</p>
<p><b>See also </b><a href="qmetaobject.html#className">className</a>().</p>
<!-- @@@superClass -->
<!-- $$$userProperty[overload1]$$$userProperty -->
<h3 class="fn" id="userProperty"><a name="userProperty"></a><span class="type"><a href="qmetaproperty.html">QMetaProperty</a></span> QMetaObject::<span class="name">userProperty</span>() const</h3>
<p>Returns the property that has the <code>USER</code> flag set to true.</p>
<p>This function was introduced in Qt 4.2.</p>
<p><b>See also </b><a href="qmetaproperty.html#isUser">QMetaProperty::isUser</a>().</p>
<!-- @@@userProperty -->
</div>
<div class="macros">
<h2>Macro Documentation</h2>
<!-- $$$Q_ARG[overload1]$$$Q_ARGconstType& -->
<h3 class="fn" id="Q_ARG"><a name="Q_ARG"></a><span class="type"><a href="qgenericargument.html">QGenericArgument</a></span> <span class="name">Q_ARG</span>(<i>Type</i>, const <span class="type">Type</span> &<i>value</i>)</h3>
<p>This macro takes a <i>Type</i> and a <i>value</i> of that type and returns a <a href="qgenericargument.html">QGenericArgument</a> object that can be passed to <a href="qmetaobject.html#invokeMethod">QMetaObject::invokeMethod</a>().</p>
<p><b>See also </b><a href="qmetaobject.html#Q_RETURN_ARG">Q_RETURN_ARG</a>().</p>
<!-- @@@Q_ARG -->
<!-- $$$Q_RETURN_ARG[overload1]$$$Q_RETURN_ARGType& -->
<h3 class="fn" id="Q_RETURN_ARG"><a name="Q_RETURN_ARG"></a><span class="type"><a href="qgenericreturnargument.html">QGenericReturnArgument</a></span> <span class="name">Q_RETURN_ARG</span>(<i>Type</i>, <span class="type">Type</span> &<i>value</i>)</h3>
<p>This macro takes a <i>Type</i> and a non-const reference to a <i>value</i> of that type and returns a <a href="qgenericreturnargument.html">QGenericReturnArgument</a> object that can be passed to <a href="qmetaobject.html#invokeMethod">QMetaObject::invokeMethod</a>().</p>
<p><b>See also </b><a href="qmetaobject.html#Q_ARG">Q_ARG</a>().</p>
<!-- @@@Q_RETURN_ARG -->
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<acronym title="Copyright">©</acronym> 2019 The Qt Company Ltd.
Documentation contributions included herein are the copyrights of
their respective owners.<br/> The documentation provided herein is licensed under the terms of the <a href="http://www.gnu.org/licenses/fdl.html">GNU Free Documentation License version 1.3</a> as published by the Free Software Foundation.<br/> Qt and respective logos are trademarks of The Qt Company Ltd. in Finland and/or other countries worldwide. All other trademarks are property
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