<?xml version="1.0" encoding="iso-8859-1"?>
<!DOCTYPE html
PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<!-- qwindowsystem_qws.cpp -->
<head>
<title>Qt 4.6: KeyboardFilter Class Reference</title>
<link href="classic.css" rel="stylesheet" type="text/css" />
</head>
<body>
<a name="//apple_ref/cpp/cl/QWSServer/KeyboardFilter"></a>
<table border="0" cellpadding="0" cellspacing="0" width="100%">
<tr>
<td align="left" valign="top" width="32"><a href="http://qt.nokia.com/"><img src="images/qt-logo.png" align="left" border="0" /></a></td>
<td width="1"> </td><td class="postheader" valign="center"><a href="index.html"><font color="#004faf">Home</font></a> · <a href="classes.html"><font color="#004faf">All Classes</font></a> · <a href="functions.html"><font color="#004faf">All Functions</font></a> · <a href="overviews.html"><font color="#004faf">Overviews</font></a></td></tr></table><h1 class="title">KeyboardFilter Class Reference<br /><span class="small-subtitle">(QWSServer::KeyboardFilter)<br />[<a href="qtgui.html">QtGui</a> module]</span>
</h1>
<p>The KeyboardFilter class is a base class for global keyboard event filters in Qt for Embedded Linux. <a href="#details">More...</a></p>
<pre> #include <<a href="qwsserver.html">QWSServer</a>></pre><ul>
<li><a href="qwsserver-keyboardfilter-members.html">List of all members, including inherited members</a></li>
</ul>
<hr />
<a name="public-functions"></a>
<h2>Public Functions</h2>
<table class="alignedsummary" border="0" cellpadding="0" cellspacing="0" width="100%">
<tr><td class="memItemLeft" align="right" valign="top">virtual </td><td class="memItemRight" valign="bottom"><b><a href="qwsserver-keyboardfilter.html#dtor.KeyboardFilter">~KeyboardFilter</a></b> ()</td></tr>
<tr><td class="memItemLeft" align="right" valign="top">virtual bool </td><td class="memItemRight" valign="bottom"><b><a href="qwsserver-keyboardfilter.html#filter">filter</a></b> ( int <i>unicode</i>, int <i>keycode</i>, int <i>modifiers</i>, bool <i>isPress</i>, bool <i>autoRepeat</i> ) = 0</td></tr>
</table>
<a name="details"></a>
<hr />
<h2>Detailed Description</h2>
<p>The KeyboardFilter class is a base class for global keyboard event filters in Qt for Embedded Linux.</p>
<p>Note that this class is only available in <a href="qt-embedded-linux.html">Qt for Embedded Linux</a>.</p>
<p>In <a href="qt-embedded-linux.html">Qt for Embedded Linux</a>, all system generated events, including keyboard events, are passed to the server application which then propagates the event to the appropriate client. The KeyboardFilter class is used to implement a global, low-level filter on the server side. The server applies the filter to all keyboard events before passing them on to the clients:</p>
<p align="center"><img src="images/qwsserver_keyboardfilter.png" /></p><p>This feature can, for example, be used to filter things like APM (advanced power management) suspended from a button without having to filter for it in all applications.</p>
<p>To add a new keyboard filter you must first create the filter by deriving from this class, reimplementing the pure virtual <a href="qwsserver-keyboardfilter.html#filter">filter</a>() function. Then you can install the filter on the server using <a href="qwsserver.html">QWSServer</a>'s <a href="qwsserver.html#addKeyboardFilter">addKeyboardFilter()</a> function. <a href="qwsserver.html">QWSServer</a> also provides a <a href="qwsserver.html#removeKeyboardFilter">removeKeyboardFilter()</a> function.</p>
<p>See also <a href="qt-embedded-architecture.html">Qt for Embedded Linux Architecture</a>, <a href="qwsserver.html">QWSServer</a>, and <a href="qwsinputmethod.html">QWSInputMethod</a>.</p>
<hr />
<h2>Member Function Documentation</h2>
<a name="//apple_ref/cpp/instm/QWSServer::KeyboardFilter/~KeyboardFilter"></a>
<h3 class="fn"><a name="dtor.KeyboardFilter"></a>KeyboardFilter::~KeyboardFilter () <tt> [virtual]</tt></h3>
<p>Destroys the keyboard filter.</p>
<a name="//apple_ref/cpp/instm/QWSServer::KeyboardFilter/filter"></a>
<h3 class="fn"><a name="filter"></a>bool KeyboardFilter::filter ( int <i>unicode</i>, int <i>keycode</i>, int <i>modifiers</i>, bool <i>isPress</i>, bool <i>autoRepeat</i> ) <tt> [pure virtual]</tt></h3>
<p>Implement this function to return true if a given key event should be stopped from being processed any further; otherwise it should return false.</p>
<p>A key event can be identified by the given <i>unicode</i> value and the <i>keycode</i>, <i>modifiers</i>, <i>isPress</i> and <i>autoRepeat</i> parameters.</p>
<p>The <i>keycode</i> parameter is the Qt keycode value as defined by the <a href="qt.html#Key-enum">Qt::Key</a> enum. The <i>modifiers</i> is an OR combination of <a href="qt.html#KeyboardModifier-enum">Qt::KeyboardModifier</a> values, indicating whether <b>Shift/Alt/Ctrl</b> keys are pressed. The <i>isPress</i> parameter is true if the event is a key press event and <i>autoRepeat</i> is true if the event is caused by an auto-repeat mechanism and not an actual key press.</p>
<p /><address><hr /><div align="center">
<table width="100%" cellspacing="0" border="0"><tr class="address">
<td width="40%" align="left">Copyright © 2010 Nokia Corporation and/or its subsidiary(-ies)</td>
<td width="20%" align="center"><a href="trademarks.html">Trademarks</a></td>
<td width="40%" align="right"><div align="right">Qt 4.6.3</div></td>
</tr></table></div></address></body>
</html>
distrib
>
Mandriva
>
current
>
i586
>
media
>
main-updates
>
by-pkgid
>
8e6051afcdb111a0317a58fb64c2abf5
>
files
>
5589
