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<h1 class="title">QDBusPendingCallWatcher Class Reference</h1>
<!-- $$$QDBusPendingCallWatcher-brief -->
<p>The QDBusPendingCallWatcher class provides a convenient way for waiting for asynchronous replies <a href="#details">More...</a></p>
<!-- @@@QDBusPendingCallWatcher -->
<pre class="cpp"> <span class="preprocessor">#include <QDBusPendingCallWatcher></span></pre><p><b>Inherits: </b><a href="qobject.html">QObject</a> and <a href="qdbuspendingcall.html">QDBusPendingCall</a>.</p>
<p>This class was introduced in Qt 4.5.</p>
<ul>
<li><a href="qdbuspendingcallwatcher-members.html">List of all members, including inherited members</a></li>
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<a name="public-functions"></a>
<h2>Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdbuspendingcallwatcher.html#QDBusPendingCallWatcher">QDBusPendingCallWatcher</a></b> ( const QDBusPendingCall & <i>call</i>, QObject * <i>parent</i> = 0 )</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdbuspendingcallwatcher.html#dtor.QDBusPendingCallWatcher">~QDBusPendingCallWatcher</a></b> ()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qdbuspendingcallwatcher.html#isFinished">isFinished</a></b> () const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qdbuspendingcallwatcher.html#waitForFinished">waitForFinished</a></b> ()</td></tr>
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<li class="fn">29 public functions inherited from <a href="qobject.html#public-functions">QObject</a></li>
<li class="fn">1 public function inherited from <a href="qdbuspendingcall.html#public-functions">QDBusPendingCall</a></li>
</ul>
<a name="signals"></a>
<h2>Signals</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qdbuspendingcallwatcher.html#finished">finished</a></b> ( QDBusPendingCallWatcher * <i>self</i> )</td></tr>
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<li class="fn">1 signal inherited from <a href="qobject.html#signals">QObject</a></li>
</ul>
<h3>Additional Inherited Members</h3>
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<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">2 static public members inherited from <a href="qdbuspendingcall.html#static-public-members">QDBusPendingCall</a></li>
<li class="fn">8 protected functions inherited from <a href="qobject.html#protected-functions">QObject</a></li>
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<a name="details"></a>
<!-- $$$QDBusPendingCallWatcher-description -->
<div class="descr">
<h2>Detailed Description</h2>
<p>The QDBusPendingCallWatcher class provides a convenient way for waiting for asynchronous replies</p>
<p>The QDBusPendingCallWatcher provides the <a href="qdbuspendingcallwatcher.html#finished">finished</a>() signal that will be emitted when a reply arrives.</p>
<p>It is usually used like the following example:</p>
<pre class="cpp"> <span class="type"><a href="qdbuspendingcall.html">QDBusPendingCall</a></span> async <span class="operator">=</span> iface<span class="operator">-</span><span class="operator">></span>asyncCall(<span class="string">"RemoteMethod"</span><span class="operator">,</span> value1<span class="operator">,</span> value2);
<span class="type">QDBusPendingCallWatcher</span> <span class="operator">*</span>watcher <span class="operator">=</span> <span class="keyword">new</span> <span class="type">QDBusPendingCallWatcher</span>(async<span class="operator">,</span> <span class="keyword">this</span>);
<span class="type"><a href="qobject.html">QObject</a></span><span class="operator">::</span>connect(watcher<span class="operator">,</span> SIGNAL(finished(<span class="type">QDBusPendingCallWatcher</span><span class="operator">*</span>))<span class="operator">,</span>
<span class="keyword">this</span><span class="operator">,</span> SLOT(callFinishedSlot(<span class="type">QDBusPendingCallWatcher</span><span class="operator">*</span>)));</pre>
<p>Note that it is not necessary to keep the original <a href="qdbuspendingcall.html">QDBusPendingCall</a> object around since QDBusPendingCallWatcher inherits from that class too.</p>
<p>The slot connected to by the above code could be something similar to the following:</p>
<pre class="cpp"> <span class="type">void</span> MyClass<span class="operator">::</span>callFinishedSlot(<span class="type">QDBusPendingCallWatcher</span> <span class="operator">*</span>call)
{
<span class="type"><a href="qdbuspendingreply.html">QDBusPendingReply</a></span><span class="operator"><</span><span class="type"><a href="qstring.html">QString</a></span><span class="operator">,</span> <span class="type"><a href="qbytearray.html">QByteArray</a></span><span class="operator">></span> reply <span class="operator">=</span> <span class="operator">*</span>call;
<span class="keyword">if</span> (reply<span class="operator">.</span>isError()) {
showError();
} <span class="keyword">else</span> {
<span class="type"><a href="qstring.html">QString</a></span> text <span class="operator">=</span> reply<span class="operator">.</span>argumentAt<span class="operator"><</span><span class="number">0</span><span class="operator">></span>();
<span class="type"><a href="qbytearray.html">QByteArray</a></span> data <span class="operator">=</span> reply<span class="operator">.</span>argumentAt<span class="operator"><</span><span class="number">1</span><span class="operator">></span>();
showReply(text<span class="operator">,</span> data);
}
call<span class="operator">-</span><span class="operator">></span>deleteLater();
}</pre>
<p>Note the use of <a href="qdbuspendingreply.html">QDBusPendingReply</a> to validate the argument types in the reply. If the reply did not contain exactly two arguments (one string and one <a href="qbytearray.html">QByteArray</a>), <a href="qdbuspendingreply.html#isError">QDBusPendingReply::isError</a>() will return true.</p>
</div>
<p><b>See also </b><a href="qdbuspendingreply.html">QDBusPendingReply</a> and <a href="qdbusabstractinterface.html#asyncCall">QDBusAbstractInterface::asyncCall</a>().</p>
<!-- @@@QDBusPendingCallWatcher -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QDBusPendingCallWatcher[overload1]$$$QDBusPendingCallWatcherconstQDBusPendingCall&QObject* -->
<h3 class="fn"><a name="QDBusPendingCallWatcher"></a>QDBusPendingCallWatcher::<span class="name">QDBusPendingCallWatcher</span> ( const <span class="type"><a href="qdbuspendingcall.html">QDBusPendingCall</a></span> & <i>call</i>, <span class="type"><a href="qobject.html">QObject</a></span> * <i>parent</i> = 0 )</h3>
<p>Creates a <a href="qdbuspendingcallwatcher.html">QDBusPendingCallWatcher</a> object to watch for replies on the asynchronous pending call <i>call</i> and sets this object's parent to <i>parent</i>.</p>
<!-- @@@QDBusPendingCallWatcher -->
<!-- $$$~QDBusPendingCallWatcher[overload1]$$$~QDBusPendingCallWatcher -->
<h3 class="fn"><a name="dtor.QDBusPendingCallWatcher"></a>QDBusPendingCallWatcher::<span class="name">~QDBusPendingCallWatcher</span> ()</h3>
<p>Destroys this object. If this <a href="qdbuspendingcallwatcher.html">QDBusPendingCallWatcher</a> object was the last reference to the unfinished pending call, the call will be canceled.</p>
<!-- @@@~QDBusPendingCallWatcher -->
<!-- $$$finished[overload1]$$$finishedQDBusPendingCallWatcher* -->
<h3 class="fn"><a name="finished"></a><span class="type">void</span> QDBusPendingCallWatcher::<span class="name">finished</span> ( <span class="type">QDBusPendingCallWatcher</span> * <i>self</i> )<tt> [signal]</tt></h3>
<p>This signal is emitted when the pending call has finished and its reply is available. The <i>self</i> parameter is a pointer to the object itself, passed for convenience so that the slot can access the properties and determine the contents of the reply.</p>
<!-- @@@finished -->
<!-- $$$isFinished[overload1]$$$isFinished -->
<h3 class="fn"><a name="isFinished"></a><span class="type">bool</span> QDBusPendingCallWatcher::<span class="name">isFinished</span> () const</h3>
<p>Returns true if the pending call has finished processing and the reply has been received.</p>
<p>Note that this function only changes state if you call <a href="qdbuspendingcallwatcher.html#waitForFinished">waitForFinished</a>() or if an external D-Bus event happens, which in general only happens if you return to the event loop execution.</p>
<p><b>See also </b><a href="qdbuspendingreply.html#isFinished">QDBusPendingReply::isFinished</a>().</p>
<!-- @@@isFinished -->
<!-- $$$waitForFinished[overload1]$$$waitForFinished -->
<h3 class="fn"><a name="waitForFinished"></a><span class="type">void</span> QDBusPendingCallWatcher::<span class="name">waitForFinished</span> ()</h3>
<p>Suspends the execution of the calling thread until the reply is received and processed. After this function returns, <a href="qdbuspendingcallwatcher.html#isFinished">isFinished</a>() should return true, indicating the reply's contents are ready to be processed.</p>
<p><b>See also </b><a href="qdbuspendingreply.html#waitForFinished">QDBusPendingReply::waitForFinished</a>().</p>
<!-- @@@waitForFinished -->
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