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Breadcrumbs go here --> <li><a href="modules.html">Modules</a></li> <li><a href="qtscript.html">QtScript</a></li> <li>QScriptable</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-functions">Public Functions</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <h1 class="title">QScriptable Class Reference</h1> <!-- $$$QScriptable-brief --> <p>The QScriptable class provides access to the Qt Script environment from Qt C++ member functions. <a href="#details">More...</a></p> <!-- @@@QScriptable --> <pre class="cpp"> <span class="preprocessor">#include <QScriptable></span></pre><p>This class was introduced in Qt 4.3.</p> <ul> <li><a href="qscriptable-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-functions"></a> <h2>Public Functions</h2> <table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> QScriptValue </td><td class="memItemRight bottomAlign"><b><a href="qscriptable.html#argument">argument</a></b> ( int <i>index</i> ) const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qscriptable.html#argumentCount">argumentCount</a></b> () const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QScriptContext * </td><td class="memItemRight bottomAlign"><b><a href="qscriptable.html#context">context</a></b> () const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QScriptEngine * </td><td class="memItemRight bottomAlign"><b><a href="qscriptable.html#engine">engine</a></b> () const</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> QScriptValue </td><td class="memItemRight bottomAlign"><b><a href="qscriptable.html#thisObject">thisObject</a></b> () const</td></tr> </table> <a name="details"></a> <!-- $$$QScriptable-description --> <div class="descr"> <h2>Detailed Description</h2> <p>The QScriptable class provides access to the Qt Script environment from Qt C++ member functions.</p> <p>With <a href="qscriptengine.html#newQObject">QScriptEngine::newQObject</a>(), you can expose the signals and slots and properties of any <a href="qobject.html">QObject</a> (or subclass) to script code. QScriptable augments this functionality by giving your C++ members access to the Qt Script environment they are invoked in; conceptually, it is similar to <a href="qobject.html#sender">QObject::sender</a>().</p> <p>By subclassing QScriptable, you get the following functions in your class: <a href="qscriptable.html#thisObject">thisObject</a>(), <a href="qscriptable.html#argumentCount">argumentCount</a>(), <a href="qscriptable.html#argument">argument</a>(), <a href="qscriptable.html#context">context</a>() and <a href="qscriptable.html#engine">engine</a>(). With these functions, you have full access to the Qt Script environment from the slots and property access functions of your class, when they are invoked from script code.</p> <p>For example, you can throw a Qt Script exception from a slot; manipulate the `this' object associated with the function call; inspect the arguments stored in the <a href="qscriptcontext.html">QScriptContext</a> to know the "real" arguments passed to the function from script code; and call script functions from your slot.</p> <p>A typical use case of QScriptable is to implement prototype objects for custom C++ types. You define the scriptable interface of your custom type in a QScriptable subclass using properties and slots; then you wrap an instance of your class using <a href="qscriptengine.html#newQObject">QScriptEngine::newQObject</a>(), and finally pass the result to <a href="qscriptengine.html#setDefaultPrototype">QScriptEngine::setDefaultPrototype</a>(). See the <a href="script-defaultprototypes.html">Default Prototypes Example</a> to see how this can be done.</p> <p>The following is what subclassing QScriptable typically looks like:</p> <pre class="cpp"> <span class="keyword">class</span> MyScriptableObject: <span class="keyword">public</span> <span class="type"><a href="qobject.html">QObject</a></span><span class="operator">,</span> <span class="keyword">protected</span> <span class="type">QScriptable</span> { Q_OBJECT <span class="operator">.</span><span class="operator">.</span><span class="operator">.</span> <span class="keyword">public</span> <span class="keyword">slots</span>: <span class="type">void</span> doSomething(); <span class="type">double</span> doSomethingElse(); }</pre> <p>The only difference from regular <a href="qobject.html">QObject</a> subclassing is that you also inherit from QScriptable.</p> <p>In the implementation of your slots, you can then use the functions inherited from QScriptable:</p> <pre class="cpp"> <span class="type">void</span> MyScriptableObject<span class="operator">::</span>doSomething() { context()<span class="operator">-</span><span class="operator">></span>throwError(<span class="string">"Threw an error from a slot"</span>); } <span class="type">double</span> MyScriptableObject<span class="operator">::</span>doSomethingElse() { <span class="keyword">return</span> qscriptvalue_cast<span class="operator"><</span><span class="type">double</span><span class="operator">></span>(thisObject()); }</pre> </div> <p><b>See also </b><a href="script-defaultprototypes.html">Default Prototypes Example</a> and <a href="qscriptengine.html#newFunction">QScriptEngine::newFunction</a>().</p> <!-- @@@QScriptable --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$argument[overload1]$$$argumentint --> <h3 class="fn"><a name="argument"></a><span class="type"><a href="qscriptvalue.html">QScriptValue</a></span> QScriptable::<span class="name">argument</span> ( <span class="type">int</span> <i>index</i> ) const</h3> <p>Returns the function argument at the given <i>index</i>, or an invalid <a href="qscriptvalue.html">QScriptValue</a> if the Qt function was not invoked from script code.</p> <p><b>See also </b><a href="qscriptable.html#argumentCount">argumentCount</a>().</p> <!-- @@@argument --> <!-- $$$argumentCount[overload1]$$$argumentCount --> <h3 class="fn"><a name="argumentCount"></a><span class="type">int</span> QScriptable::<span class="name">argumentCount</span> () const</h3> <p>Returns the number of arguments passed to the function in this invocation, or -1 if the Qt function was not invoked from script code.</p> <p><b>See also </b><a href="qscriptable.html#argument">argument</a>().</p> <!-- @@@argumentCount --> <!-- $$$context[overload1]$$$context --> <h3 class="fn"><a name="context"></a><span class="type"><a href="qscriptcontext.html">QScriptContext</a></span> * QScriptable::<span class="name">context</span> () const</h3> <p>Returns a pointer to the <a href="qscriptcontext.html">QScriptContext</a> associated with the current Qt function call, or 0 if the Qt function was not invoked from script code.</p> <!-- @@@context --> <!-- $$$engine[overload1]$$$engine --> <h3 class="fn"><a name="engine"></a><span class="type"><a href="qscriptengine.html">QScriptEngine</a></span> * QScriptable::<span class="name">engine</span> () const</h3> <p>Returns a pointer to the <a href="qscriptengine.html">QScriptEngine</a> associated with the current Qt function call, or 0 if the Qt function was not invoked from script code.</p> <!-- @@@engine --> <!-- $$$thisObject[overload1]$$$thisObject --> <h3 class="fn"><a name="thisObject"></a><span class="type"><a href="qscriptvalue.html">QScriptValue</a></span> QScriptable::<span class="name">thisObject</span> () const</h3> <p>Returns the `this' object associated with the current Qt function call, or an invalid <a href="qscriptvalue.html">QScriptValue</a> if the Qt function was not invoked from script code.</p> <!-- @@@thisObject --> </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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