mirror of
https://github.com/xiaoyifang/goldendict-ng.git
synced 2024-12-12 15:04:05 +00:00
102 lines
5.3 KiB
HTML
102 lines
5.3 KiB
HTML
<?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">
|
|
<!-- trivial.qdoc -->
|
|
<head>
|
|
<title>A Trivial Example</title>
|
|
<link href="classic.css" rel="stylesheet" type="text/css" />
|
|
</head>
|
|
<body>
|
|
<table border="0" cellpadding="0" cellspacing="0" width="100%">
|
|
<tr>
|
|
<td align="left" valign="top" width="32"><img src="images/qt-logo.png" align="left" width="57" height="67" border="0" /></td>
|
|
<td width="1"> </td><td class="postheader" valign="center"><a href="index.html"><font color="#004faf">Home</font></a></td>
|
|
</tr></table><h1 class="title">A Trivial Example<br /><span class="subtitle"></span>
|
|
</h1>
|
|
<p>The application in this example has a log-view that displays messages sent by further instances of the same application.</p>
|
|
<p>The example demonstrates the use of the <a href="qtsingleapplication.html">QtSingleApplication</a> class to detect and communicate with a running instance of the application using the sendMessage() API. The messageReceived() signal is used to display received messages in a <a href="http://qt.nokia.com/doc/4.6/qtextedit.html">QTextEdit</a> log.</p>
|
|
<pre><span class="comment"> /****************************************************************************
|
|
**
|
|
** Copyright (C) 2013 Digia Plc and/or its subsidiary(-ies).
|
|
** Contact: http://www.qt-project.org/legal
|
|
**
|
|
** This file is part of the Qt Solutions component.
|
|
**
|
|
** You may use this file under the terms of the BSD license as follows:
|
|
**
|
|
** "Redistribution and use in source and binary forms, with or without
|
|
** modification, are permitted provided that the following conditions are
|
|
** met:
|
|
** * Redistributions of source code must retain the above copyright
|
|
** notice, this list of conditions and the following disclaimer.
|
|
** * Redistributions in binary form must reproduce the above copyright
|
|
** notice, this list of conditions and the following disclaimer in
|
|
** the documentation and/or other materials provided with the
|
|
** distribution.
|
|
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
|
|
** the names of its contributors may be used to endorse or promote
|
|
** products derived from this software without specific prior written
|
|
** permission.
|
|
**
|
|
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
|
|
**
|
|
****************************************************************************/</span>
|
|
|
|
#include <qtsingleapplication.h>
|
|
#include <QtGui/QTextEdit>
|
|
|
|
class TextEdit : public QTextEdit
|
|
{
|
|
Q_OBJECT
|
|
public:
|
|
TextEdit(QWidget *parent = 0)
|
|
: QTextEdit(parent)
|
|
{}
|
|
public slots:
|
|
void append(const QString &str)
|
|
{
|
|
QTextEdit::append(str);
|
|
}
|
|
};
|
|
|
|
#include "main.moc"
|
|
|
|
int main(int argc, char **argv)
|
|
{
|
|
QtSingleApplication instance(argc, argv);</pre>
|
|
<p>The example has only the <tt>main</tt> entry point function. A <a href="qtsingleapplication.html">QtSingleApplication</a> object is created immediately.</p>
|
|
<pre> if (instance.sendMessage("Wake up!"))
|
|
return 0;</pre>
|
|
<p>If another instance of this application is already running, sendMessage() will succeed, and this instance just exits immediately.</p>
|
|
<pre> TextEdit logview;
|
|
logview.setReadOnly(true);
|
|
logview.show();</pre>
|
|
<p>Otherwise the instance continues as normal and creates the user interface.</p>
|
|
<pre> instance.setActivationWindow(&logview);
|
|
|
|
QObject::connect(&instance, SIGNAL(messageReceived(const QString&)),
|
|
&logview, SLOT(append(const QString&)));
|
|
|
|
return instance.exec();</pre>
|
|
<p>The <tt>logview</tt> object is also set as the application's activation window. Every time a message is received, the window will be raised and activated automatically.</p>
|
|
<p>The messageReceived() signal is also connected to the <a href="http://qt.nokia.com/doc/4.6/qtextedit.html">QTextEdit</a>'s append() slot. Every message received from further instances of this application will be displayed in the log.</p>
|
|
<p>Finally the event loop is entered.</p>
|
|
<p /><address><hr /><div align="center">
|
|
<table width="100%" cellspacing="0" border="0"><tr class="address">
|
|
<td width="30%" align="left">Copyright © 2010 Nokia Corporation and/or its subsidiary(-ies)</td>
|
|
<td width="40%" align="center"><a href="http://qt.nokia.com/doc/trademarks.html">Trademarks</a></td>
|
|
<td width="30%" align="right"><div align="right">Qt Solutions</div></td>
|
|
</tr></table></div></address></body>
|
|
</html>
|