<?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>main.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-gestures-imagegestures-example.html">Image Gestures Example</a></td><td >main.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">main.cpp Example File</h1> <span class="subtitle">gestures/imagegestures/main.cpp</span> <!-- $$$gestures/imagegestures/main.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 "mainwidget.h"</span> <span class="keyword">static</span> <span class="type">void</span> showHelp(<span class="type"><a href="../qtcore/qcommandlineparser.html">QCommandLineParser</a></span> <span class="operator">&</span>parser<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> errorMessage <span class="operator">=</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span>()) { <span class="type"><a href="../qtcore/qstring.html">QString</a></span> text; <span class="type"><a href="../qtcore/qtextstream.html">QTextStream</a></span> str(<span class="operator">&</span>text); str <span class="operator"><</span><span class="operator"><</span> <span class="string">"<html><head/><body>"</span>; <span class="keyword">if</span> (<span class="operator">!</span>errorMessage<span class="operator">.</span>isEmpty()) str <span class="operator"><</span><span class="operator"><</span> <span class="string">"<p>"</span> <span class="operator"><</span><span class="operator"><</span> errorMessage <span class="operator"><</span><span class="operator"><</span> <span class="string">"</p>"</span>; str <span class="operator"><</span><span class="operator"><</span> <span class="string">"<pre>"</span> <span class="operator"><</span><span class="operator"><</span> parser<span class="operator">.</span>helpText() <span class="operator"><</span><span class="operator"><</span> <span class="string">"</pre></body></html>"</span>; <span class="type"><a href="qmessagebox.html">QMessageBox</a></span> box(errorMessage<span class="operator">.</span>isEmpty() <span class="operator">?</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Information : <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Warning<span class="operator">,</span> <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>applicationDisplayName()<span class="operator">,</span> text<span class="operator">,</span> <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>Ok); box<span class="operator">.</span>setTextInteractionFlags(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>TextBrowserInteraction); box<span class="operator">.</span>exec(); } <span class="type">int</span> main(<span class="type">int</span> argc<span class="operator">,</span> <span class="type">char</span> <span class="operator">*</span>argv<span class="operator">[</span><span class="operator">]</span>) { <span class="type"><a href="qapplication.html">QApplication</a></span> app(argc<span class="operator">,</span> argv); <span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>setApplicationVersion(QT_VERSION_STR); <span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>setApplicationName(<span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">"imagegestures"</span>)); <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>setApplicationDisplayName(<span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">"Image Gestures Example"</span>)); <span class="type"><a href="../qtcore/qcommandlineparser.html">QCommandLineParser</a></span> commandLineParser; <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> disablePanOption(<span class="string">"no-pan"</span><span class="operator">,</span> <span class="string">"Disable pan gesture"</span>); commandLineParser<span class="operator">.</span>addOption(disablePanOption); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> disablePinchOption(<span class="string">"no-pinch"</span><span class="operator">,</span> <span class="string">"Disable pinch gesture"</span>); commandLineParser<span class="operator">.</span>addOption(disablePinchOption); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> disableSwipeOption(<span class="string">"no-swipe"</span><span class="operator">,</span> <span class="string">"Disable swipe gesture"</span>); commandLineParser<span class="operator">.</span>addOption(disableSwipeOption); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qcommandlineoption.html">QCommandLineOption</a></span> helpOption <span class="operator">=</span> commandLineParser<span class="operator">.</span>addHelpOption(); commandLineParser<span class="operator">.</span>addPositionalArgument(<span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">"Directory"</span>)<span class="operator">,</span> <span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">"Directory to display"</span>)); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> description <span class="operator">=</span> <span class="type"><a href="../qtgui/qguiapplication.html">QGuiApplication</a></span><span class="operator">::</span>applicationDisplayName() <span class="operator">+</span> QLatin1String(<span class="string">"\n\nEnable \"debug\" on the logging category \"qt.examples.imagegestures\" in order to\n"</span> <span class="string">"in order to obtain verbose information about Qt's gesture event processing,\n"</span> <span class="string">"for example by setting the environment variables QT_LOGGING_RULES to\n"</span> <span class="string">"qt.examples.imagegestures.debug=true\n"</span>); commandLineParser<span class="operator">.</span>setApplicationDescription(description); commandLineParser<span class="operator">.</span>process(<span class="type"><a href="../qtcore/qcoreapplication.html">QCoreApplication</a></span><span class="operator">::</span>arguments()); <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> arguments <span class="operator">=</span> commandLineParser<span class="operator">.</span>positionalArguments(); <span class="keyword">if</span> (<span class="operator">!</span>arguments<span class="operator">.</span>isEmpty() <span class="operator">&</span><span class="operator">&</span> <span class="operator">!</span><span class="type"><a href="../qtcore/qfileinfo.html">QFileInfo</a></span>(arguments<span class="operator">.</span>front())<span class="operator">.</span>isDir()) { showHelp(commandLineParser<span class="operator">,</span> QLatin1Char(<span class="char">'"'</span>) <span class="operator">+</span> <span class="type"><a href="../qtcore/qdir.html">QDir</a></span><span class="operator">::</span>toNativeSeparators(arguments<span class="operator">.</span>front()) <span class="operator">+</span> <span class="type"><a href="../qtcore/qstring.html#QStringLiteral">QStringLiteral</a></span>(<span class="string">"\" is not a directory."</span>)); <span class="keyword">return</span> <span class="operator">-</span><span class="number">1</span>; } <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator"><</span><span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>GestureType<span class="operator">></span> gestures; <span class="keyword">if</span> (<span class="operator">!</span>commandLineParser<span class="operator">.</span>isSet(disablePanOption)) gestures <span class="operator"><</span><span class="operator"><</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>PanGesture; <span class="keyword">if</span> (<span class="operator">!</span>commandLineParser<span class="operator">.</span>isSet(disablePinchOption)) gestures <span class="operator"><</span><span class="operator"><</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>PinchGesture; <span class="keyword">if</span> (<span class="operator">!</span>commandLineParser<span class="operator">.</span>isSet(disableSwipeOption)) gestures <span class="operator"><</span><span class="operator"><</span> <span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>SwipeGesture; MainWidget w; w<span class="operator">.</span>grabGestures(gestures); w<span class="operator">.</span>show(); <span class="keyword">if</span> (arguments<span class="operator">.</span>isEmpty()) { <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstringlist.html">QStringList</a></span> picturesLocations <span class="operator">=</span> <span class="type"><a href="../qtcore/qstandardpaths.html">QStandardPaths</a></span><span class="operator">::</span>standardLocations(<span class="type"><a href="../qtcore/qstandardpaths.html">QStandardPaths</a></span><span class="operator">::</span>PicturesLocation); <span class="keyword">const</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span> directory <span class="operator">=</span> <span class="type"><a href="qfiledialog.html">QFileDialog</a></span><span class="operator">::</span>getExistingDirectory(<span class="operator">&</span>w<span class="operator">,</span> <span class="string">"Select image folder"</span><span class="operator">,</span> picturesLocations<span class="operator">.</span>isEmpty() <span class="operator">?</span> <span class="type"><a href="../qtcore/qstring.html">QString</a></span>() : picturesLocations<span class="operator">.</span>front()); <span class="keyword">if</span> (directory<span class="operator">.</span>isEmpty()) <span class="keyword">return</span> <span class="number">0</span>; arguments<span class="operator">.</span>append(directory); } w<span class="operator">.</span>openDirectory(arguments<span class="operator">.</span>front()); <span class="keyword">return</span> app<span class="operator">.</span>exec(); } </pre> </div> <!-- @@@gestures/imagegestures/main.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>