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<td >Qt 5.9</td><td ><a href="qtcore-index.html">Qt Core</a></td><td ><a href="qtcore-module.html">C++ Classes</a></td><td >QFutureWatcher</td></tr></table><table class="buildversion"><tr>
<td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</td>
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<h3><a name="toc">Contents</a></h3>
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<li class="level1"><a href="#public-functions">Public Functions</a></li>
<li class="level1"><a href="#public-slots">Public Slots</a></li>
<li class="level1"><a href="#signals">Signals</a></li>
<li class="level1"><a href="#details">Detailed Description</a></li>
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<h1 class="title">QFutureWatcher Class</h1>
<!-- $$$QFutureWatcher-brief -->
<p>The <a href="qfuturewatcher.html">QFutureWatcher</a> class allows monitoring a <a href="qfuture.html">QFuture</a> using signals and slots. <a href="#details">More...</a></p>
<!-- @@@QFutureWatcher -->
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<tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QFutureWatcher></span>
</td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += core</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 4.4</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> QFutureWatcherBase</td></tr></table></div><ul>
<li><a href="qfuturewatcher-members.html">List of all members, including inherited members</a></li>
</ul>
<p><b>Note:</b> All functions in this class are reentrant.</p>
<a name="public-functions"></a>
<h2 id="public-functions">Public Functions</h2>
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<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#QFutureWatcher">QFutureWatcher</a></b>(QObject *<i>parent</i> = nullptr)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#dtor.QFutureWatcher">~QFutureWatcher</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QFuture<T> </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#future">future</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#isCanceled">isCanceled</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#isFinished">isFinished</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#isPaused">isPaused</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#isRunning">isRunning</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> bool </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#isStarted">isStarted</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressMaximum">progressMaximum</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressMinimum">progressMinimum</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> QString </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressText">progressText</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> int </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressValue">progressValue</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> T </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#result">result</a></b>() const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> T </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#resultAt">resultAt</a></b>(int <i>index</i>) const</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#setFuture">setFuture</a></b>(const QFuture<T> &<i>future</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#setPendingResultsLimit">setPendingResultsLimit</a></b>(int <i>limit</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#waitForFinished">waitForFinished</a></b>()</td></tr>
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<ul>
<li class="fn">12 public functions inherited from <a href="qfuturewatcherbase.html#public-functions">QFutureWatcherBase</a></li>
<li class="fn">32 public functions inherited from <a href="qobject.html#public-functions">QObject</a></li>
</ul>
<a name="public-slots"></a>
<h2 id="public-slots">Public Slots</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#cancel">cancel</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#pause">pause</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#resume">resume</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#setPaused">setPaused</a></b>(bool <i>paused</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#togglePaused">togglePaused</a></b>()</td></tr>
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<ul>
<li class="fn">5 public slots inherited from <a href="qfuturewatcherbase.html#public-slots">QFutureWatcherBase</a></li>
<li class="fn">1 public slot inherited from <a href="qobject.html#public-slots">QObject</a></li>
</ul>
<a name="signals"></a>
<h2 id="signals">Signals</h2>
<div class="table"><table class="alignedsummary">
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#canceled">canceled</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#finished">finished</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#paused">paused</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressRangeChanged">progressRangeChanged</a></b>(int <i>minimum</i>, int <i>maximum</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressTextChanged">progressTextChanged</a></b>(const QString &<i>progressText</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#progressValueChanged">progressValueChanged</a></b>(int <i>progressValue</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#resultReadyAt">resultReadyAt</a></b>(int <i>index</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#resultsReadyAt">resultsReadyAt</a></b>(int <i>beginIndex</i>, int <i>endIndex</i>)</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#resumed">resumed</a></b>()</td></tr>
<tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qfuturewatcher.html#started">started</a></b>()</td></tr>
</table></div>
<ul>
<li class="fn">10 signals inherited from <a href="qfuturewatcherbase.html#signals">QFutureWatcherBase</a></li>
<li class="fn">2 signals 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">11 static public members inherited from <a href="qobject.html#static-public-members">QObject</a></li>
<li class="fn">2 protected functions inherited from <a href="qfuturewatcherbase.html#protected-functions">QFutureWatcherBase</a></li>
<li class="fn">9 protected functions inherited from <a href="qobject.html#protected-functions">QObject</a></li>
</ul>
<a name="details"></a>
<!-- $$$QFutureWatcher-description -->
<div class="descr">
<h2 id="details">Detailed Description</h2>
<p>The <a href="qfuturewatcher.html">QFutureWatcher</a> class allows monitoring a <a href="qfuture.html">QFuture</a> using signals and slots.</p>
<p><a href="qfuturewatcher.html">QFutureWatcher</a> provides information and notifications about a <a href="qfuture.html">QFuture</a>. Use the <a href="qfuturewatcher.html#setFuture">setFuture</a>() function to start watching a particular <a href="qfuture.html">QFuture</a>. The <a href="qfuturewatcher.html#future">future</a>() function returns the future set with <a href="qfuturewatcher.html#setFuture">setFuture</a>().</p>
<p>For convenience, several of <a href="qfuture.html">QFuture</a>'s functions are also available in <a href="qfuturewatcher.html">QFutureWatcher</a>: <a href="qfuturewatcher.html#progressValue">progressValue</a>(), <a href="qfuturewatcher.html#progressMinimum">progressMinimum</a>(), <a href="qfuturewatcher.html#progressMaximum">progressMaximum</a>(), <a href="qfuturewatcher.html#progressText">progressText</a>(), <a href="qfuturewatcher.html#isStarted">isStarted</a>(), <a href="qfuturewatcher.html#isFinished">isFinished</a>(), <a href="qfuturewatcher.html#isRunning">isRunning</a>(), <a href="qfuturewatcher.html#isCanceled">isCanceled</a>(), <a href="qfuturewatcher.html#isPaused">isPaused</a>(), <a href="qfuturewatcher.html#waitForFinished">waitForFinished</a>(), <a href="qfuturewatcher.html#result">result</a>(), and <a href="qfuturewatcher.html#resultAt">resultAt</a>(). The <a href="qfuturewatcher.html#cancel">cancel</a>(), <a href="qfuturewatcher.html#setPaused">setPaused</a>(), <a href="qfuturewatcher.html#pause">pause</a>(), <a href="qfuturewatcher.html#resume">resume</a>(), and <a href="qfuturewatcher.html#togglePaused">togglePaused</a>() functions are slots in <a href="qfuturewatcher.html">QFutureWatcher</a>.</p>
<p>Status changes are reported via the <a href="qfuturewatcher.html#started">started</a>(), <a href="qfuturewatcher.html#finished">finished</a>(), <a href="qfuturewatcher.html#canceled">canceled</a>(), <a href="qfuturewatcher.html#paused">paused</a>(), <a href="qfuturewatcher.html#resumed">resumed</a>(), <a href="qfuturewatcher.html#resultReadyAt">resultReadyAt</a>(), and <a href="qfuturewatcher.html#resultsReadyAt">resultsReadyAt</a>() signals. Progress information is provided from the <a href="qfuturewatcher.html#progressRangeChanged">progressRangeChanged</a>(), void <a href="qfuturewatcher.html#progressValueChanged">progressValueChanged</a>(), and <a href="qfuturewatcher.html#progressTextChanged">progressTextChanged</a>() signals.</p>
<p>Throttling control is provided by the <a href="qfuturewatcher.html#setPendingResultsLimit">setPendingResultsLimit</a>() function. When the number of pending <a href="qfuturewatcher.html#resultReadyAt">resultReadyAt</a>() or <a href="qfuturewatcher.html#resultsReadyAt">resultsReadyAt</a>() signals exceeds the limit, the computation represented by the future will be throttled automatically. The computation will resume once the number of pending signals drops below the limit.</p>
<p>Example: Starting a computation and getting a slot callback when it's finished:</p>
<pre class="cpp">
<span class="comment">// Instantiate the objects and connect to the finished signal.</span>
MyClass myObject;
<span class="type"><a href="qfuturewatcher.html#QFutureWatcher">QFutureWatcher</a></span><span class="operator"><</span><span class="type">int</span><span class="operator">></span> watcher;
connect(<span class="operator">&</span>watcher<span class="operator">,</span> SIGNAL(finished())<span class="operator">,</span> <span class="operator">&</span>myObject<span class="operator">,</span> SLOT(handleFinished()));
<span class="comment">// Start the computation.</span>
<span class="type"><a href="qfuture.html">QFuture</a></span><span class="operator"><</span><span class="type">int</span><span class="operator">></span> future <span class="operator">=</span> <span class="type"><a href="../qtconcurrent/qtconcurrent.html">QtConcurrent</a></span><span class="operator">::</span>run(<span class="operator">.</span><span class="operator">.</span><span class="operator">.</span>);
watcher<span class="operator">.</span>setFuture(future);
</pre>
<p>Be aware that not all asynchronous computations can be canceled or paused. For example, the future returned by <a href="../qtconcurrent/qtconcurrent.html#run">QtConcurrent::run</a>() cannot be canceled; but the future returned by <a href="../qtconcurrent/qtconcurrent.html#mappedReduced-1">QtConcurrent::mappedReduced</a>() can.</p>
<p><a href="qfuturewatcher.html">QFutureWatcher</a><void> is specialized to not contain any of the result fetching functions. Any <a href="qfuture.html">QFuture</a><T> can be watched by a <a href="qfuturewatcher.html">QFutureWatcher</a><void> as well. This is useful if only status or progress information is needed; not the actual result data.</p>
</div>
<p><b>See also </b><a href="qfuture.html">QFuture</a> and <a href="../qtconcurrent/qtconcurrent-index.html">Qt Concurrent</a>.</p>
<!-- @@@QFutureWatcher -->
<div class="func">
<h2>Member Function Documentation</h2>
<!-- $$$QFutureWatcher[overload1]$$$QFutureWatcherQObject* -->
<h3 class="fn" id="QFutureWatcher"><a name="QFutureWatcher"></a>QFutureWatcher::<span class="name">QFutureWatcher</span>(<span class="type"><a href="qobject.html#QObject">QObject</a></span> *<i>parent</i> = nullptr)</h3>
<p>Constructs a new <a href="qfuturewatcher.html">QFutureWatcher</a> with the given <i>parent</i>.</p>
<!-- @@@QFutureWatcher -->
<!-- $$$~QFutureWatcher[overload1]$$$~QFutureWatcher -->
<h3 class="fn" id="dtor.QFutureWatcher"><a name="dtor.QFutureWatcher"></a>QFutureWatcher::<span class="name">~QFutureWatcher</span>()</h3>
<p>Destroys the <a href="qfuturewatcher.html">QFutureWatcher</a>.</p>
<!-- @@@~QFutureWatcher -->
<!-- $$$cancel[overload1]$$$cancel -->
<h3 class="fn" id="cancel"><a name="cancel"></a><code>[slot] </code><span class="type">void</span> QFutureWatcher::<span class="name">cancel</span>()</h3>
<p>Cancels the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>(). Note that the cancelation is asynchronous. Use <a href="qfuturewatcher.html#waitForFinished">waitForFinished</a>() after calling cancel() when you need synchronous cancelation.</p>
<p>Currently available results may still be accessed on a canceled <a href="qfuture.html">QFuture</a>, but new results will <i>not</i> become available after calling this function. Also, this <a href="qfuturewatcher.html">QFutureWatcher</a> will not deliver progress and result ready signals once canceled. This includes the <a href="qfuturewatcher.html#progressValueChanged">progressValueChanged</a>(), <a href="qfuturewatcher.html#progressRangeChanged">progressRangeChanged</a>(), <a href="qfuturewatcher.html#progressTextChanged">progressTextChanged</a>(), <a href="qfuturewatcher.html#resultReadyAt">resultReadyAt</a>(), and <a href="qfuturewatcher.html#resultsReadyAt">resultsReadyAt</a>() signals.</p>
<p>Be aware that not all asynchronous computations can be canceled. For example, the <a href="qfuture.html">QFuture</a> returned by <a href="../qtconcurrent/qtconcurrent.html#run">QtConcurrent::run</a>() cannot be canceled; but the <a href="qfuture.html">QFuture</a> returned by <a href="../qtconcurrent/qtconcurrent.html#mappedReduced-1">QtConcurrent::mappedReduced</a>() can.</p>
<!-- @@@cancel -->
<!-- $$$canceled[overload1]$$$canceled -->
<h3 class="fn" id="canceled"><a name="canceled"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">canceled</span>()</h3>
<p>This signal is emitted if the watched future is canceled.</p>
<!-- @@@canceled -->
<!-- $$$finished[overload1]$$$finished -->
<h3 class="fn" id="finished"><a name="finished"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">finished</span>()</h3>
<p>This signal is emitted when the watched future finishes.</p>
<!-- @@@finished -->
<!-- $$$future[overload1]$$$future -->
<h3 class="fn" id="future"><a name="future"></a><span class="type"><a href="qfuture.html">QFuture</a></span><<span class="type">T</span>> QFutureWatcher::<span class="name">future</span>() const</h3>
<p>Returns the watched future.</p>
<p><b>See also </b><a href="qfuturewatcher.html#setFuture">setFuture</a>().</p>
<!-- @@@future -->
<!-- $$$isCanceled[overload1]$$$isCanceled -->
<h3 class="fn" id="isCanceled"><a name="isCanceled"></a><span class="type">bool</span> QFutureWatcher::<span class="name">isCanceled</span>() const</h3>
<p>Returns <code>true</code> if the asynchronous computation has been canceled with the <a href="qfuturewatcher.html#cancel">cancel</a>() function; otherwise returns <code>false</code>.</p>
<p>Be aware that the computation may still be running even though this function returns <code>true</code>. See <a href="qfuturewatcher.html#cancel">cancel</a>() for more details.</p>
<!-- @@@isCanceled -->
<!-- $$$isFinished[overload1]$$$isFinished -->
<h3 class="fn" id="isFinished"><a name="isFinished"></a><span class="type">bool</span> QFutureWatcher::<span class="name">isFinished</span>() const</h3>
<p>Returns <code>true</code> if the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>() has finished, or if no future has been set; otherwise returns <code>false</code>.</p>
<!-- @@@isFinished -->
<!-- $$$isPaused[overload1]$$$isPaused -->
<h3 class="fn" id="isPaused"><a name="isPaused"></a><span class="type">bool</span> QFutureWatcher::<span class="name">isPaused</span>() const</h3>
<p>Returns <code>true</code> if the asynchronous computation has been paused with the <a href="qfuturewatcher.html#pause">pause</a>() function; otherwise returns <code>false</code>.</p>
<p>Be aware that the computation may still be running even though this function returns <code>true</code>. See <a href="qfuturewatcher.html#setPaused">setPaused</a>() for more details.</p>
<p><b>See also </b><a href="qfuturewatcher.html#setPaused">setPaused</a>() and <a href="qfuturewatcher.html#togglePaused">togglePaused</a>().</p>
<!-- @@@isPaused -->
<!-- $$$isRunning[overload1]$$$isRunning -->
<h3 class="fn" id="isRunning"><a name="isRunning"></a><span class="type">bool</span> QFutureWatcher::<span class="name">isRunning</span>() const</h3>
<p>Returns <code>true</code> if the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>() is currently running; otherwise returns <code>false</code>.</p>
<!-- @@@isRunning -->
<!-- $$$isStarted[overload1]$$$isStarted -->
<h3 class="fn" id="isStarted"><a name="isStarted"></a><span class="type">bool</span> QFutureWatcher::<span class="name">isStarted</span>() const</h3>
<p>Returns <code>true</code> if the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>() has been started; otherwise returns <code>false</code>.</p>
<!-- @@@isStarted -->
<!-- $$$pause[overload1]$$$pause -->
<h3 class="fn" id="pause"><a name="pause"></a><code>[slot] </code><span class="type">void</span> QFutureWatcher::<span class="name">pause</span>()</h3>
<p>Pauses the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>(). This is a convenience method that simply calls <a href="qfuturewatcher.html#setPaused">setPaused</a>(true).</p>
<p><b>See also </b><a href="qfuturewatcher.html#resume">resume</a>().</p>
<!-- @@@pause -->
<!-- $$$paused[overload1]$$$paused -->
<h3 class="fn" id="paused"><a name="paused"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">paused</span>()</h3>
<p>This signal is emitted when the watched future is paused.</p>
<p><b>See also </b><a href="qfuturewatcher.html#setPaused">setPaused</a>().</p>
<!-- @@@paused -->
<!-- $$$progressMaximum[overload1]$$$progressMaximum -->
<h3 class="fn" id="progressMaximum"><a name="progressMaximum"></a><span class="type">int</span> QFutureWatcher::<span class="name">progressMaximum</span>() const</h3>
<p>Returns the maximum <a href="qfuturewatcher.html#progressValue">progressValue</a>().</p>
<p><b>See also </b><a href="qfuturewatcher.html#progressValue">progressValue</a>() and <a href="qfuturewatcher.html#progressMinimum">progressMinimum</a>().</p>
<!-- @@@progressMaximum -->
<!-- $$$progressMinimum[overload1]$$$progressMinimum -->
<h3 class="fn" id="progressMinimum"><a name="progressMinimum"></a><span class="type">int</span> QFutureWatcher::<span class="name">progressMinimum</span>() const</h3>
<p>Returns the minimum <a href="qfuturewatcher.html#progressValue">progressValue</a>().</p>
<p><b>See also </b><a href="qfuturewatcher.html#progressValue">progressValue</a>() and <a href="qfuturewatcher.html#progressMaximum">progressMaximum</a>().</p>
<!-- @@@progressMinimum -->
<!-- $$$progressRangeChanged[overload1]$$$progressRangeChangedintint -->
<h3 class="fn" id="progressRangeChanged"><a name="progressRangeChanged"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">progressRangeChanged</span>(<span class="type">int</span> <i>minimum</i>, <span class="type">int</span> <i>maximum</i>)</h3>
<p>The progress range for the watched future has changed to <i>minimum</i> and <i>maximum</i></p>
<!-- @@@progressRangeChanged -->
<!-- $$$progressText[overload1]$$$progressText -->
<h3 class="fn" id="progressText"><a name="progressText"></a><span class="type"><a href="qstring.html">QString</a></span> QFutureWatcher::<span class="name">progressText</span>() const</h3>
<p>Returns the (optional) textual representation of the progress as reported by the asynchronous computation.</p>
<p>Be aware that not all computations provide a textual representation of the progress, and as such, this function may return an empty string.</p>
<!-- @@@progressText -->
<!-- $$$progressTextChanged[overload1]$$$progressTextChangedconstQString& -->
<h3 class="fn" id="progressTextChanged"><a name="progressTextChanged"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">progressTextChanged</span>(const <span class="type"><a href="qstring.html">QString</a></span> &<i>progressText</i>)</h3>
<p>This signal is emitted when the watched future reports textual progress information, <i>progressText</i>.</p>
<!-- @@@progressTextChanged -->
<!-- $$$progressValue[overload1]$$$progressValue -->
<h3 class="fn" id="progressValue"><a name="progressValue"></a><span class="type">int</span> QFutureWatcher::<span class="name">progressValue</span>() const</h3>
<p>Returns the current progress value, which is between the <a href="qfuturewatcher.html#progressMinimum">progressMinimum</a>() and <a href="qfuturewatcher.html#progressMaximum">progressMaximum</a>().</p>
<p><b>See also </b><a href="qfuturewatcher.html#progressMinimum">progressMinimum</a>() and <a href="qfuturewatcher.html#progressMaximum">progressMaximum</a>().</p>
<!-- @@@progressValue -->
<!-- $$$progressValueChanged[overload1]$$$progressValueChangedint -->
<h3 class="fn" id="progressValueChanged"><a name="progressValueChanged"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">progressValueChanged</span>(<span class="type">int</span> <i>progressValue</i>)</h3>
<p>This signal is emitted when the watched future reports progress, <i>progressValue</i> gives the current progress. In order to avoid overloading the GUI event loop, <a href="qfuturewatcher.html">QFutureWatcher</a> limits the progress signal emission rate. This means that listeners connected to this slot might not get all progress reports the future makes. The last progress update (where <i>progressValue</i> equals the maximum value) will always be delivered.</p>
<!-- @@@progressValueChanged -->
<!-- $$$result[overload1]$$$result -->
<h3 class="fn" id="result"><a name="result"></a><span class="type">T</span> QFutureWatcher::<span class="name">result</span>() const</h3>
<p>Returns the first result in the <a href="qfuturewatcher.html#future">future</a>(). If the result is not immediately available, this function will block and wait for the result to become available. This is a convenience method for calling <a href="qfuturewatcher.html#resultAt">resultAt</a>(0).</p>
<p><b>See also </b><a href="qfuturewatcher.html#resultAt">resultAt</a>().</p>
<!-- @@@result -->
<!-- $$$resultAt[overload1]$$$resultAtint -->
<h3 class="fn" id="resultAt"><a name="resultAt"></a><span class="type">T</span> QFutureWatcher::<span class="name">resultAt</span>(<span class="type">int</span> <i>index</i>) const</h3>
<p>Returns the result at <i>index</i> in the <a href="qfuturewatcher.html#future">future</a>(). If the result is not immediately available, this function will block and wait for the result to become available.</p>
<p><b>See also </b><a href="qfuturewatcher.html#result">result</a>().</p>
<!-- @@@resultAt -->
<!-- $$$resultReadyAt[overload1]$$$resultReadyAtint -->
<h3 class="fn" id="resultReadyAt"><a name="resultReadyAt"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">resultReadyAt</span>(<span class="type">int</span> <i>index</i>)</h3>
<p>This signal is emitted when the watched future reports a ready result at <i>index</i>. If the future reports multiple results, the index will indicate which one it is. Results can be reported out-of-order. To get the result, call <a href="qfuturewatcher.html#future">future</a>().result(index);</p>
<!-- @@@resultReadyAt -->
<!-- $$$resultsReadyAt[overload1]$$$resultsReadyAtintint -->
<h3 class="fn" id="resultsReadyAt"><a name="resultsReadyAt"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">resultsReadyAt</span>(<span class="type">int</span> <i>beginIndex</i>, <span class="type">int</span> <i>endIndex</i>)</h3>
<p>This signal is emitted when the watched future reports ready results. The results are indexed from <i>beginIndex</i> to <i>endIndex</i>.</p>
<!-- @@@resultsReadyAt -->
<!-- $$$resume[overload1]$$$resume -->
<h3 class="fn" id="resume"><a name="resume"></a><code>[slot] </code><span class="type">void</span> QFutureWatcher::<span class="name">resume</span>()</h3>
<p>Resumes the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>(). This is a convenience method that simply calls <a href="qfuturewatcher.html#setPaused">setPaused</a>(false).</p>
<p><b>See also </b><a href="qfuturewatcher.html#pause">pause</a>().</p>
<!-- @@@resume -->
<!-- $$$resumed[overload1]$$$resumed -->
<h3 class="fn" id="resumed"><a name="resumed"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">resumed</span>()</h3>
<p>This signal is emitted when the watched future is resumed.</p>
<!-- @@@resumed -->
<!-- $$$setFuture[overload1]$$$setFutureconstQFuture<T>& -->
<h3 class="fn" id="setFuture"><a name="setFuture"></a><span class="type">void</span> QFutureWatcher::<span class="name">setFuture</span>(const <span class="type"><a href="qfuture.html">QFuture</a></span><<span class="type">T</span>> &<i>future</i>)</h3>
<p>Starts watching the given <i>future</i>.</p>
<p>One of the signals might be emitted for the current state of the <i>future</i>. For example, if the future is already stopped, the finished signal will be emitted.</p>
<p>To avoid a race condition, it is important to call this function <i>after</i> doing the connections.</p>
<p><b>See also </b><a href="qfuturewatcher.html#future">future</a>().</p>
<!-- @@@setFuture -->
<!-- $$$setPaused[overload1]$$$setPausedbool -->
<h3 class="fn" id="setPaused"><a name="setPaused"></a><code>[slot] </code><span class="type">void</span> QFutureWatcher::<span class="name">setPaused</span>(<span class="type">bool</span> <i>paused</i>)</h3>
<p>If <i>paused</i> is true, this function pauses the asynchronous computation represented by the <a href="qfuturewatcher.html#future">future</a>(). If the computation is already paused, this function does nothing. This <a href="qfuturewatcher.html">QFutureWatcher</a> will stop delivering progress and result ready signals while the future is paused. Signal delivery will continue once the computation is resumed.</p>
<p>If <i>paused</i> is false, this function resumes the asynchronous computation. If the computation was not previously paused, this function does nothing.</p>
<p>Be aware that not all computations can be paused. For example, the <a href="qfuture.html">QFuture</a> returned by <a href="../qtconcurrent/qtconcurrent.html#run">QtConcurrent::run</a>() cannot be paused; but the <a href="qfuture.html">QFuture</a> returned by <a href="../qtconcurrent/qtconcurrent.html#mappedReduced-1">QtConcurrent::mappedReduced</a>() can.</p>
<p><b>See also </b><a href="qfuturewatcher.html#paused">paused</a>(), <a href="qfuturewatcher.html#pause">pause</a>(), <a href="qfuturewatcher.html#resume">resume</a>(), and <a href="qfuturewatcher.html#togglePaused">togglePaused</a>().</p>
<!-- @@@setPaused -->
<!-- $$$setPendingResultsLimit[overload1]$$$setPendingResultsLimitint -->
<h3 class="fn" id="setPendingResultsLimit"><a name="setPendingResultsLimit"></a><span class="type">void</span> QFutureWatcher::<span class="name">setPendingResultsLimit</span>(<span class="type">int</span> <i>limit</i>)</h3>
<p>The setPendingResultsLimit() provides throttling control. When the number of pending <a href="qfuturewatcher.html#resultReadyAt">resultReadyAt</a>() or <a href="qfuturewatcher.html#resultsReadyAt">resultsReadyAt</a>() signals exceeds the <i>limit</i>, the computation represented by the future will be throttled automatically. The computation will resume once the number of pending signals drops below the <i>limit</i>.</p>
<!-- @@@setPendingResultsLimit -->
<!-- $$$started[overload1]$$$started -->
<h3 class="fn" id="started"><a name="started"></a><code>[signal] </code><span class="type">void</span> QFutureWatcher::<span class="name">started</span>()</h3>
<p>This signal is emitted when this <a href="qfuturewatcher.html">QFutureWatcher</a> starts watching the future set with <a href="qfuturewatcher.html#setFuture">setFuture</a>().</p>
<!-- @@@started -->
<!-- $$$togglePaused[overload1]$$$togglePaused -->
<h3 class="fn" id="togglePaused"><a name="togglePaused"></a><code>[slot] </code><span class="type">void</span> QFutureWatcher::<span class="name">togglePaused</span>()</h3>
<p>Toggles the paused state of the asynchronous computation. In other words, if the computation is currently paused, calling this function resumes it; if the computation is running, it becomes paused. This is a convenience method for calling <a href="qfuturewatcher.html#setPaused">setPaused</a>(!<a href="qfuturewatcher.html#isPaused">isPaused</a>()).</p>
<p><b>See also </b><a href="qfuturewatcher.html#setPaused">setPaused</a>(), <a href="qfuturewatcher.html#pause">pause</a>(), and <a href="qfuturewatcher.html#resume">resume</a>().</p>
<!-- @@@togglePaused -->
<!-- $$$waitForFinished[overload1]$$$waitForFinished -->
<h3 class="fn" id="waitForFinished"><a name="waitForFinished"></a><span class="type">void</span> QFutureWatcher::<span class="name">waitForFinished</span>()</h3>
<p>Waits for the asynchronous computation to finish (including <a href="qfuturewatcher.html#cancel">cancel</a>()ed computations).</p>
<!-- @@@waitForFinished -->
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