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Breadcrumbs go here --> <li><a href="modules.html">Modules</a></li> <li><a href="qtgui.html">QtGui</a></li> <li>QWSScreenSaver</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">QWSScreenSaver Class Reference</h1> <!-- $$$QWSScreenSaver-brief --> <p>The QWSScreenSaver class is a base class for screensavers in Qt for Embedded Linux. <a href="#details">More...</a></p> <!-- @@@QWSScreenSaver --> <pre class="cpp"> <span class="preprocessor">#include <QWSScreenSaver></span></pre><ul> <li><a href="qwsscreensaver-members.html">List of all members, including inherited members</a></li> </ul> <a name="public-functions"></a> <h2>Public Functions</h2> <table class="alignedsummary"> <tr><td class="memItemLeft rightAlign topAlign"> virtual </td><td class="memItemRight bottomAlign"><b><a href="qwsscreensaver.html#dtor.QWSScreenSaver">~QWSScreenSaver</a></b> ()</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual void </td><td class="memItemRight bottomAlign"><b><a href="qwsscreensaver.html#restore">restore</a></b> () = 0</td></tr> <tr><td class="memItemLeft rightAlign topAlign"> virtual bool </td><td class="memItemRight bottomAlign"><b><a href="qwsscreensaver.html#save">save</a></b> ( int <i>level</i> ) = 0</td></tr> </table> <a name="details"></a> <!-- $$$QWSScreenSaver-description --> <div class="descr"> <h2>Detailed Description</h2> <p>The QWSScreenSaver class is a base class for screensavers in Qt for Embedded Linux.</p> <p>When running <a href="qt-embedded-linux.html">Qt for Embedded Linux</a> applications, it is the server application that installs and controls the screensaver. <a href="qt-embedded-linux.html">Qt for Embedded Linux</a> supports multilevel screen saving; i.e., it is possible to specify several different levels of screen responsiveness. For example, you can choose to first turn off the light before you fully activate the screensaver.</p> <p>Note that there exists no default screensaver implementation.</p> <p>To create a custom screensaver, derive from this class and reimplement the <a href="qwsscreensaver.html#restore">restore</a>() and <a href="qwsscreensaver.html#save">save</a>() functions. These functions are called whenever the screensaver is activated or deactivated, respectively. Once an instance of your custom screensaver is created, you can use the <a href="qwsserver.html#setScreenSaver">QWSServer::setScreenSaver</a>() function to install it.</p> </div> <p><b>See also </b><a href="qwsserver.html">QWSServer</a>, <a href="qscreen.html">QScreen</a>, and <a href="qt-embedded-linux.html">Qt for Embedded Linux</a>.</p> <!-- @@@QWSScreenSaver --> <div class="func"> <h2>Member Function Documentation</h2> <!-- $$$~QWSScreenSaver[overload1]$$$~QWSScreenSaver --> <h3 class="fn"><a name="dtor.QWSScreenSaver"></a>QWSScreenSaver::<span class="name">~QWSScreenSaver</span> ()<tt> [virtual]</tt></h3> <p>Reimplement this function to destroy the screensaver.</p> <!-- @@@~QWSScreenSaver --> <!-- $$$restore[overload1]$$$restore --> <h3 class="fn"><a name="restore"></a><span class="type">void</span> QWSScreenSaver::<span class="name">restore</span> ()<tt> [pure virtual]</tt></h3> <p>Implement this function to deactivate the screensaver, restoring the previously saved screen.</p> <p><b>See also </b><a href="qwsscreensaver.html#save">save</a>() and <a href="qwsserver.html#screenSaverActivate">QWSServer::screenSaverActivate</a>().</p> <!-- @@@restore --> <!-- $$$save[overload1]$$$saveint --> <h3 class="fn"><a name="save"></a><span class="type">bool</span> QWSScreenSaver::<span class="name">save</span> ( <span class="type">int</span> <i>level</i> )<tt> [pure virtual]</tt></h3> <p>Implement this function to activate the screensaver, saving the current screen.</p> <p><a href="qt-embedded-linux.html">Qt for Embedded Linux</a> supports multilevel screen saving; i.e., it is possible to specify several different levels of screen responsiveness. For example, you can choose to first turn off the light before you fully activate the screensaver. Use the <a href="qwsserver.html#setScreenSaverIntervals">QWSServer::setScreenSaverIntervals</a>() to specify the time intervals between the different levels.</p> <p>This function should return true if the screensaver successfully enters the given <i>level</i>; otherwise it should return false.</p> <p><b>See also </b><a href="qwsscreensaver.html#restore">restore</a>() and <a href="qwsserver.html#screenSaverActivate">QWSServer::screenSaverActivate</a>().</p> <!-- @@@save --> </div> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2013 Digia Plc and/or its subsidiaries. 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