<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- qmetadatawritercontrol.cpp --> <title>QMetaDataWriterControl Class | Qt Multimedia 5.12.2</title> <link rel="stylesheet" type="text/css" href="style/offline-simple.css" /> <script type="text/javascript"> document.getElementsByTagName("link").item(0).setAttribute("href", "style/offline.css"); // loading style sheet breaks anchors that were jumped to before // so force jumping to anchor again setTimeout(function() { var anchor = location.hash; // need to jump to different anchor first (e.g. none) location.hash = "#"; setTimeout(function() { location.hash = anchor; }, 0); }, 0); </script> </head> <body> <div class="header" id="qtdocheader"> <div class="main"> <div class="main-rounded"> <div class="navigationbar"> <table><tr> <td >Qt 5.12</td><td ><a href="qtmultimedia-index.html">Qt Multimedia</a></td><td ><a href="qtmultimedia-modules.html">C++ Classes</a></td><td >QMetaDataWriterControl</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtmultimedia-index.html">Qt 5.12.2 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"> <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="#signals">Signals</a></li> <li class="level1"><a href="#static-public-members">Static Public Members</a></li> <li class="level1"><a href="#protected-functions">Protected Functions</a></li> <li class="level1"><a href="#macros">Macros</a></li> <li class="level1"><a href="#details">Detailed Description</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">QMetaDataWriterControl Class</h1> <!-- $$$QMetaDataWriterControl-brief --> <p>The <a href="qmetadatawritercontrol.html">QMetaDataWriterControl</a> class provides write access to the meta-data of a <a href="qmediaservice.html">QMediaService</a>'s media. <a href="#details">More...</a></p> <!-- @@@QMetaDataWriterControl --> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QMetaDataWriterControl></span> </td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += multimedia</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <a href="qmediacontrol.html">QMediaControl</a></td></tr></table></div><ul> <li><a href="qmetadatawritercontrol-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-functions"></a> <h2 id="public-functions">Public Functions</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#dtor.QMetaDataWriterControl">~QMetaDataWriterControl</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual QStringList </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#availableMetaData">availableMetaData</a></b>() const = 0</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#isMetaDataAvailable">isMetaDataAvailable</a></b>() const = 0</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#isWritable">isWritable</a></b>() const = 0</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual QVariant </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#metaData">metaData</a></b>(const QString &<i>key</i>) const = 0</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#setMetaData">setMetaData</a></b>(const QString &<i>key</i>, const QVariant &<i>value</i>) = 0</td></tr> </table></div> <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="qmetadatawritercontrol.html#metaDataAvailableChanged">metaDataAvailableChanged</a></b>(bool <i>available</i>)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#metaDataChanged">metaDataChanged</a></b>()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#metaDataChanged-1">metaDataChanged</a></b>(const QString &<i>key</i>, const QVariant &<i>value</i>)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> void </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#writableChanged">writableChanged</a></b>(bool <i>writable</i>)</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"> const QMetaObject </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#staticMetaObject-var">staticMetaObject</a></b></td></tr> </table></div> <a name="protected-functions"></a> <h2 id="protected-functions">Protected Functions</h2> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#QMetaDataWriterControl">QMetaDataWriterControl</a></b>(QObject *<i>parent</i> = nullptr)</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"> </td><td class="memItemRight bottomAlign"><b><a href="qmetadatawritercontrol.html#QMetaDataWriterControl_iid">QMetaDataWriterControl_iid</a></b></td></tr> </table></div> <a name="details"></a> <!-- $$$QMetaDataWriterControl-description --> <div class="descr"> <h2 id="details">Detailed Description</h2> <p>The <a href="qmetadatawritercontrol.html">QMetaDataWriterControl</a> class provides write access to the meta-data of a <a href="qmediaservice.html">QMediaService</a>'s media.</p> <p>If a <a href="qmediaservice.html">QMediaService</a> can provide write access to the meta-data of its current media it will implement <a href="qmetadatawritercontrol.html">QMetaDataWriterControl</a>. This control provides functions for both retrieving and setting meta-data values. Meta-data may be addressed by the keys defined in the <a href="qmediametadata.html">QMediaMetaData</a> namespace.</p> <p>The functionality provided by this control is exposed to application code by the meta-data members of <a href="qmediaobject.html">QMediaObject</a>, and so meta-data access is potentially available in any of the media object classes. Any media service may implement QMetaDataControl.</p> <p>The interface name of <a href="qmetadatawritercontrol.html">QMetaDataWriterControl</a> is <code>org.qt-project.qt.metadatawritercontrol/5.0</code> as defined in <a href="qmetadatawritercontrol.html#QMetaDataWriterControl_iid">QMetaDataWriterControl_iid</a>.</p> </div> <p><b>See also </b><a href="qmediaservice.html#requestControl-1">QMediaService::requestControl</a>() and <a href="qmediaobject.html">QMediaObject</a>.</p> <!-- @@@QMetaDataWriterControl --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QMetaDataWriterControl[overload1]$$$QMetaDataWriterControlQObject* --> <h3 class="fn" id="QMetaDataWriterControl"><a name="QMetaDataWriterControl"></a><code>[protected] </code>QMetaDataWriterControl::<span class="name">QMetaDataWriterControl</span>(<span class="type">QObject</span> *<i>parent</i> = nullptr)</h3> <p>Construct a <a href="qmetadatawritercontrol.html">QMetaDataWriterControl</a> with <i>parent</i>. This class is meant as a base class for service specific meta data providers so this constructor is protected.</p> <!-- @@@QMetaDataWriterControl --> <!-- $$$~QMetaDataWriterControl[overload1]$$$~QMetaDataWriterControl --> <h3 class="fn" id="dtor.QMetaDataWriterControl"><a name="dtor.QMetaDataWriterControl"></a><code>[virtual] </code>QMetaDataWriterControl::<span class="name">~QMetaDataWriterControl</span>()</h3> <p>Destroy the meta-data writer control.</p> <!-- @@@~QMetaDataWriterControl --> <!-- $$$availableMetaData[overload1]$$$availableMetaData --> <h3 class="fn" id="availableMetaData"><a name="availableMetaData"></a><code>[pure virtual] </code><span class="type">QStringList</span> QMetaDataWriterControl::<span class="name">availableMetaData</span>() const</h3> <!-- @@@availableMetaData --> <!-- $$$isMetaDataAvailable[overload1]$$$isMetaDataAvailable --> <h3 class="fn" id="isMetaDataAvailable"><a name="isMetaDataAvailable"></a><code>[pure virtual] </code><span class="type">bool</span> QMetaDataWriterControl::<span class="name">isMetaDataAvailable</span>() const</h3> <!-- @@@isMetaDataAvailable --> <!-- $$$isWritable[overload1]$$$isWritable --> <h3 class="fn" id="isWritable"><a name="isWritable"></a><code>[pure virtual] </code><span class="type">bool</span> QMetaDataWriterControl::<span class="name">isWritable</span>() const</h3> <!-- @@@isWritable --> <!-- $$$metaData[overload1]$$$metaDataconstQString& --> <h3 class="fn" id="metaData"><a name="metaData"></a><code>[pure virtual] </code><span class="type">QVariant</span> QMetaDataWriterControl::<span class="name">metaData</span>(const <span class="type">QString</span> &<i>key</i>) const</h3> <p><b>See also </b><a href="qmetadatawritercontrol.html#setMetaData">setMetaData</a>().</p> <!-- @@@metaData --> <!-- $$$metaDataAvailableChanged[overload1]$$$metaDataAvailableChangedbool --> <h3 class="fn" id="metaDataAvailableChanged"><a name="metaDataAvailableChanged"></a><code>[signal] </code><span class="type">void</span> QMetaDataWriterControl::<span class="name">metaDataAvailableChanged</span>(<span class="type">bool</span> <i>available</i>)</h3> <!-- @@@metaDataAvailableChanged --> <!-- $$$metaDataChanged[overload1]$$$metaDataChanged --> <h3 class="fn" id="metaDataChanged"><a name="metaDataChanged"></a><code>[signal] </code><span class="type">void</span> QMetaDataWriterControl::<span class="name">metaDataChanged</span>()</h3> <p><b>Note:</b> Signal <i>metaDataChanged</i> is overloaded in this class. To connect to this signal by using the function pointer syntax, Qt provides a convenient helper for obtaining the function pointer as shown in this example:<pre class="cpp"> connect(metaDataWriterControl<span class="operator">,</span> <span class="type">QOverload</span><span class="operator"><</span><span class="operator">></span><span class="operator">::</span>of(<span class="operator">&</span><span class="type"><a href="qmetadatawritercontrol.html#QMetaDataWriterControl">QMetaDataWriterControl</a></span><span class="operator">::</span>metaDataChanged)<span class="operator">,</span> <span class="operator">[</span><span class="operator">=</span><span class="operator">]</span>(){ <span class="comment">/* ... */</span> }); </pre> <!-- @@@metaDataChanged --> <!-- $$$metaDataChanged$$$metaDataChangedconstQString&constQVariant& --> <h3 class="fn" id="metaDataChanged-1"><a name="metaDataChanged-1"></a><code>[signal] </code><span class="type">void</span> QMetaDataWriterControl::<span class="name">metaDataChanged</span>(const <span class="type">QString</span> &<i>key</i>, const <span class="type">QVariant</span> &<i>value</i>)</h3> <p><b>Note:</b> Signal <i>metaDataChanged</i> is overloaded in this class. To connect to this signal by using the function pointer syntax, Qt provides a convenient helper for obtaining the function pointer as shown in this example:<pre class="cpp"> connect(metaDataWriterControl<span class="operator">,</span> <span class="type">QOverload</span><span class="operator"><</span><span class="keyword">const</span> <span class="type">QString</span> <span class="operator">&</span><span class="operator">,</span> <span class="keyword">const</span> <span class="type">QVariant</span> <span class="operator">&</span><span class="operator">></span><span class="operator">::</span>of(<span class="operator">&</span><span class="type"><a href="qmetadatawritercontrol.html#QMetaDataWriterControl">QMetaDataWriterControl</a></span><span class="operator">::</span>metaDataChanged)<span class="operator">,</span> <span class="operator">[</span><span class="operator">=</span><span class="operator">]</span>(<span class="keyword">const</span> <span class="type">QString</span> <span class="operator">&</span>key<span class="operator">,</span> <span class="keyword">const</span> <span class="type">QVariant</span> <span class="operator">&</span>value){ <span class="comment">/* ... */</span> }); </pre> <!-- @@@metaDataChanged --> <!-- $$$setMetaData[overload1]$$$setMetaDataconstQString&constQVariant& --> <h3 class="fn" id="setMetaData"><a name="setMetaData"></a><code>[pure virtual] </code><span class="type">void</span> QMetaDataWriterControl::<span class="name">setMetaData</span>(const <span class="type">QString</span> &<i>key</i>, const <span class="type">QVariant</span> &<i>value</i>)</h3> <p><b>See also </b><a href="qmetadatawritercontrol.html#metaData">metaData</a>().</p> <!-- @@@setMetaData --> <!-- $$$writableChanged[overload1]$$$writableChangedbool --> <h3 class="fn" id="writableChanged"><a name="writableChanged"></a><code>[signal] </code><span class="type">void</span> QMetaDataWriterControl::<span class="name">writableChanged</span>(<span class="type">bool</span> <i>writable</i>)</h3> <!-- @@@writableChanged --> </div> <div class="macros"> <h2>Macro Documentation</h2> <!-- $$$QMetaDataWriterControl_iid[overload1]$$$QMetaDataWriterControl_iid --> <h3 class="fn" id="QMetaDataWriterControl_iid"><a name="QMetaDataWriterControl_iid"></a><span class="name">QMetaDataWriterControl_iid</span></h3> <p><code>org.qt-project.qt.metadatawritercontrol/5.0</code></p> <p>Defines the interface name of the <a href="qmetadatawritercontrol.html">QMetaDataWriterControl</a> class.</p> <!-- @@@QMetaDataWriterControl_iid --> </div> </div> </div> </div> </div> </div> <div class="footer"> <p> <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 of their respective owners. </p> </div> </body> </html>