<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <!-- qdbusinterface.cpp --> <title>QDBusInterface Class | Qt D-Bus</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 5.9</td><td ><a href="qtdbus-index.html">Qt D-Bus</a></td><td ><a href="qtdbus-module.html">C++ Classes</a></td><td >QDBusInterface</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</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="#details">Detailed Description</a></li> </ul> </div> <div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">QDBusInterface Class</h1> <!-- $$$QDBusInterface-brief --> <p>The <a href="qdbusinterface.html">QDBusInterface</a> class is a proxy for interfaces on remote objects. <a href="#details">More...</a></p> <!-- @@@QDBusInterface --> <div class="table"><table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> Header:</td><td class="memItemRight bottomAlign"> <span class="preprocessor">#include <QDBusInterface></span> </td></tr><tr><td class="memItemLeft rightAlign topAlign"> qmake:</td><td class="memItemRight bottomAlign"> QT += dbus</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Since:</td><td class="memItemRight bottomAlign"> Qt 4.2</td></tr><tr><td class="memItemLeft rightAlign topAlign"> Inherits:</td><td class="memItemRight bottomAlign"> <a href="qdbusabstractinterface.html">QDBusAbstractInterface</a></td></tr></table></div><ul> <li><a href="qdbusinterface-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"> </td><td class="memItemRight bottomAlign"><b><a href="qdbusinterface.html#QDBusInterface">QDBusInterface</a></b>(const QString &<i>service</i>, const QString &<i>path</i>, const QString &<i>interface</i> = QString(), const QDBusConnection &<i>connection</i> = QDBusConnection::sessionBus(), QObject *<i>parent</i> = Q_NULLPTR)</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> </td><td class="memItemRight bottomAlign"><b><a href="qdbusinterface.html#dtor.QDBusInterface">~QDBusInterface</a></b>()</td></tr> </table></div> <ul> <li class="fn">15 public functions inherited from <a href="qdbusabstractinterface.html#public-functions">QDBusAbstractInterface</a></li> <li class="fn">32 public functions inherited from <a href="../qtcore/qobject.html#public-functions">QObject</a></li> </ul> <h3>Additional Inherited Members</h3> <ul> <li class="fn">1 property inherited from <a href="../qtcore/qobject.html#properties">QObject</a></li> <li class="fn">1 public slot inherited from <a href="../qtcore/qobject.html#public-slots">QObject</a></li> <li class="fn">2 signals inherited from <a href="../qtcore/qobject.html#signals">QObject</a></li> <li class="fn">1 public variable inherited from <a href="../qtcore/qobject.html#public-variables">QObject</a></li> <li class="fn">10 static public members inherited from <a href="../qtcore/qobject.html#static-public-members">QObject</a></li> <li class="fn">9 protected functions inherited from <a href="../qtcore/qobject.html#protected-functions">QObject</a></li> <li class="fn">2 protected variables inherited from <a href="../qtcore/qobject.html#protected-variables">QObject</a></li> </ul> <a name="details"></a> <!-- $$$QDBusInterface-description --> <div class="descr"> <h2 id="details">Detailed Description</h2> <p>The <a href="qdbusinterface.html">QDBusInterface</a> class is a proxy for interfaces on remote objects.</p> <p><a href="qdbusinterface.html">QDBusInterface</a> is a generic accessor class that is used to place calls to remote objects, connect to signals exported by remote objects and get/set the value of remote properties. This class is useful for dynamic access to remote objects: that is, when you do not have a generated code that represents the remote interface.</p> <p>Calls are usually placed by using the <a href="qdbusabstractinterface.html#call">call</a>() function, which constructs the message, sends it over the bus, waits for the reply and decodes the reply. Signals are connected to by using the normal <a href="../qtcore/qobject.html#connect-4">QObject::connect</a>() function. Finally, properties are accessed using the <a href="../qtcore/qobject.html#property">QObject::property</a>() and <a href="../qtcore/qobject.html#setProperty">QObject::setProperty</a>() functions.</p> <p>The following code snippet demonstrates how to perform a mathematical operation of <code>"2 + 2"</code> in a remote application called <code>com.example.Calculator</code>, accessed via the session bus.</p> <pre class="cpp"> <span class="type"><a href="qdbusinterface.html#QDBusInterface">QDBusInterface</a></span> remoteApp( <span class="string">"com.example.Calculator"</span><span class="operator">,</span> <span class="string">"/Calculator/Operations"</span><span class="operator">,</span> <span class="string">"org.mathematics.RPNCalculator"</span> ); remoteApp<span class="operator">.</span>call( <span class="string">"PushOperand"</span><span class="operator">,</span> <span class="number">2</span> ); remoteApp<span class="operator">.</span>call( <span class="string">"PushOperand"</span><span class="operator">,</span> <span class="number">2</span> ); remoteApp<span class="operator">.</span>call( <span class="string">"ExecuteOperation"</span><span class="operator">,</span> <span class="string">"+"</span> ); <span class="type"><a href="qdbusreply.html">QDBusReply</a></span><span class="operator"><</span><span class="type">int</span><span class="operator">></span> reply <span class="operator">=</span> remoteApp<span class="operator">.</span>call( <span class="string">"PopOperand"</span> ); <span class="keyword">if</span> ( reply<span class="operator">.</span>isValid() ) printf( <span class="string">"%d"</span><span class="operator">,</span> reply<span class="operator">.</span>value() ); <span class="comment">// prints 4</span> </pre> </div> <p><b>See also </b><a href="qdbusxml2cpp.html">Qt D-Bus XML compiler (qdbusxml2cpp)</a>.</p> <!-- @@@QDBusInterface --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$QDBusInterface[overload1]$$$QDBusInterfaceconstQString&constQString&constQString&constQDBusConnection&QObject* --> <h3 class="fn" id="QDBusInterface"><a name="QDBusInterface"></a>QDBusInterface::<span class="name">QDBusInterface</span>(const <span class="type"><a href="../qtcore/qstring.html">QString</a></span> &<i>service</i>, const <span class="type"><a href="../qtcore/qstring.html">QString</a></span> &<i>path</i>, const <span class="type"><a href="../qtcore/qstring.html">QString</a></span> &<i>interface</i> = QString(), const <span class="type"><a href="qdbusconnection.html">QDBusConnection</a></span> &<i>connection</i> = QDBusConnection::sessionBus(), <span class="type"><a href="../qtcore/qobject.html#QObject">QObject</a></span> *<i>parent</i> = Q_NULLPTR)</h3> <p>Creates a dynamic <a href="qdbusinterface.html">QDBusInterface</a> object associated with the interface <i>interface</i> on object at path <i>path</i> on service <i>service</i>, using the given <i>connection</i>. If <i>interface</i> is an empty string, the object created will refer to the merging of all interfaces found in that object.</p> <p><i>parent</i> is passed to the base class constructor.</p> <p>If the remote service <i>service</i> is not present or if an error occurs trying to obtain the description of the remote interface <i>interface</i>, the object created will not be valid (see <a href="qdbusabstractinterface.html#isValid">isValid</a>()).</p> <!-- @@@QDBusInterface --> <!-- $$$~QDBusInterface[overload1]$$$~QDBusInterface --> <h3 class="fn" id="dtor.QDBusInterface"><a name="dtor.QDBusInterface"></a>QDBusInterface::<span class="name">~QDBusInterface</span>()</h3> <p>Destroy the object interface and frees up any resource used.</p> <!-- @@@~QDBusInterface --> </div> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2017 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>