<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html> <html lang="en"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>echowindow.cpp Example File | Qt Widgets 5.12.6</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="qtwidgets-index.html">Qt Widgets</a></td><td ><a href="qtwidgets-tools-echoplugin-example.html">Echo Plugin Example</a></td><td >echowindow.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtwidgets-index.html">Qt 5.12.6 Reference Documentation</a></td> </tr></table> </div> </div> <div class="content"> <div class="line"> <div class="content mainContent"> <div class="sidebar"><div class="sidebar-content" id="sidebar-content"></div></div> <h1 class="title">echowindow.cpp Example File</h1> <span class="subtitle">tools/echoplugin/echowindow/echowindow.cpp</span> <!-- $$$tools/echoplugin/echowindow/echowindow.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2016 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** Commercial License Usage ** Licensees holding valid commercial Qt licenses may use this file in ** accordance with the commercial license agreement provided with the ** Software or, alternatively, in accordance with the terms contained in ** a written agreement between you and The Qt Company. For licensing terms ** and conditions see https://www.qt.io/terms-conditions. For further ** information use the contact form at https://www.qt.io/contact-us. ** ** BSD License Usage ** Alternatively, 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 The Qt Company Ltd 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." ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include <QtWidgets></span> <span class="preprocessor">#include "echowindow.h"</span> EchoWindow<span class="operator">::</span>EchoWindow() { createGUI(); setLayout(layout); setWindowTitle(<span class="string">"Echo Plugin Example"</span>); <span class="keyword">if</span> (<span class="operator">!</span>loadPlugin()) { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>information(<span class="keyword">this</span><span class="operator">,</span> <span class="string">"Error"</span><span class="operator">,</span> <span class="string">"Could not load the plugin"</span>); lineEdit<span class="operator">-</span><span class="operator">></span>setEnabled(<span class="keyword">false</span>); button<span class="operator">-</span><span class="operator">></span>setEnabled(<span class="keyword">false</span>); } } <span class="type">void</span> EchoWindow<span class="operator">::</span>sendEcho() { <span class="type"><a href="../qtcore/qstring.html">QString</a></span> text <span class="operator">=</span> echoInterface<span class="operator">-</span><span class="operator">></span>echo(lineEdit<span class="operator">-</span><span class="operator">></span>text()); label<span class="operator">-</span><span class="operator">></span>setText(text); } <span class="type">void</span> EchoWindow<span class="operator">::</span>createGUI() { lineEdit <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qlineedit.html">QLineEdit</a></span>; label <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>; label<span class="operator">-</span><span class="operator">></span>setFrameStyle(<span class="type"><a href="qframe.html">QFrame</a></span><span class="operator">::</span>Box <span class="operator">|</span> <span class="type"><a href="qframe.html">QFrame</a></span><span class="operator">::</span>Plain); button <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qpushbutton.html">QPushButton</a></span>(tr(<span class="string">"Send Message"</span>)); connect(lineEdit<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qlineedit.html">QLineEdit</a></span><span class="operator">::</span>editingFinished<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>EchoWindow<span class="operator">::</span>sendEcho); connect(button<span class="operator">,</span> <span class="operator">&</span><span class="type"><a href="qpushbutton.html">QPushButton</a></span><span class="operator">::</span>clicked<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> <span class="operator">&</span>EchoWindow<span class="operator">::</span>sendEcho); layout <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgridlayout.html">QGridLayout</a></span>; layout<span class="operator">-</span><span class="operator">></span>addWidget(<span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>(tr(<span class="string">"Message:"</span>))<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">0</span>); layout<span class="operator">-</span><span class="operator">></span>addWidget(lineEdit<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">1</span>); layout<span class="operator">-</span><span class="operator">></span>addWidget(<span class="keyword">new</span> <span class="type"><a href="qlabel.html">QLabel</a></span>(tr(<span class="string">"Answer:"</span>))<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">0</span>); layout<span class="operator">-</span><span class="operator">></span>addWidget(label<span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">1</span>); layout<span class="operator">-</span><span class="operator">></span>addWidget(button<span class="operator">,</span> <span class="number">2</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>AlignRight); layout<span class="operator">-</span><span class="operator">></span>setSizeConstraint(<span class="type"><a href="qlayout.html">QLayout</a></span><span class="operator">::</span>SetFixedSize); } bool EchoWindow<span class="operator">::</span>loadPlugin() { <span class="type"><a href="../qtcore/qdir.html">QDir</a></span> pluginsDir(<a href="qapplication.html#qApp">qApp</a><span class="operator">-</span><span class="operator">></span>applicationDirPath()); <span class="preprocessor">#if defined(Q_OS_WIN)</span> <span class="keyword">if</span> (pluginsDir<span class="operator">.</span>dirName()<span class="operator">.</span>toLower() <span class="operator">=</span><span class="operator">=</span> <span class="string">"debug"</span> <span class="operator">|</span><span class="operator">|</span> pluginsDir<span class="operator">.</span>dirName()<span class="operator">.</span>toLower() <span class="operator">=</span><span class="operator">=</span> <span class="string">"release"</span>) pluginsDir<span class="operator">.</span>cdUp(); <span class="preprocessor">#elif defined(Q_OS_MAC)</span> <span class="keyword">if</span> (pluginsDir<span class="operator">.</span>dirName() <span class="operator">=</span><span class="operator">=</span> <span class="string">"MacOS"</span>) { pluginsDir<span class="operator">.</span>cdUp(); pluginsDir<span class="operator">.</span>cdUp(); pluginsDir<span class="operator">.</span>cdUp(); } <span class="preprocessor">#endif</span> pluginsDir<span class="operator">.</span>cd(<span class="string">"plugins"</span>); foreach (<span class="type"><a href="../qtcore/qstring.html">QString</a></span> fileName<span class="operator">,</span> pluginsDir<span class="operator">.</span>entryList(<span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>Files)) { <span class="type"><a href="../qtcore/qpluginloader.html">QPluginLoader</a></span> pluginLoader(pluginsDir<span class="operator">.</span>absoluteFilePath(fileName)); <span class="type"><a href="../qtcore/qobject.html">QObject</a></span> <span class="operator">*</span>plugin <span class="operator">=</span> pluginLoader<span class="operator">.</span>instance(); <span class="keyword">if</span> (plugin) { echoInterface <span class="operator">=</span> qobject_cast<span class="operator"><</span>EchoInterface <span class="operator">*</span><span class="operator">></span>(plugin); <span class="keyword">if</span> (echoInterface) <span class="keyword">return</span> <span class="keyword">true</span>; } } <span class="keyword">return</span> <span class="keyword">false</span>; } </pre> </div> <!-- @@@tools/echoplugin/echowindow/echowindow.cpp --> </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>