<?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>mainwindow.cpp Example File | Qt Widgets 5.12.2</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-undoframework-example.html">Undo Framework Example</a></td><td >mainwindow.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtwidgets-index.html">Qt 5.12.2 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">mainwindow.cpp Example File</h1> <span class="subtitle">tools/undoframework/mainwindow.cpp</span> <!-- $$$tools/undoframework/mainwindow.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 "mainwindow.h"</span> <span class="preprocessor">#include "diagramscene.h"</span> <span class="preprocessor">#include "diagramitem.h"</span> <span class="preprocessor">#include "commands.h"</span> MainWindow<span class="operator">::</span>MainWindow() { undoStack <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qundostack.html">QUndoStack</a></span>(<span class="keyword">this</span>); createActions(); createMenus(); createUndoView(); diagramScene <span class="operator">=</span> <span class="keyword">new</span> DiagramScene(); <span class="type"><a href="../qtgui/qbrush.html">QBrush</a></span> pixmapBrush(<span class="type"><a href="../qtgui/qpixmap.html">QPixmap</a></span>(<span class="string">":/images/cross.png"</span>)<span class="operator">.</span>scaled(<span class="number">30</span><span class="operator">,</span> <span class="number">30</span>)); diagramScene<span class="operator">-</span><span class="operator">></span>setBackgroundBrush(pixmapBrush); diagramScene<span class="operator">-</span><span class="operator">></span>setSceneRect(<span class="type"><a href="../qtcore/qrect.html">QRect</a></span>(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">500</span><span class="operator">,</span> <span class="number">500</span>)); connect(diagramScene<span class="operator">,</span> SIGNAL(itemMoved(DiagramItem<span class="operator">*</span><span class="operator">,</span><span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>))<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(itemMoved(DiagramItem<span class="operator">*</span><span class="operator">,</span><span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>))); setWindowTitle(<span class="string">"Undo Framework"</span>); <span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span> <span class="operator">*</span>view <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span>(diagramScene); setCentralWidget(view); resize(<span class="number">700</span><span class="operator">,</span> <span class="number">500</span>); } <span class="type">void</span> MainWindow<span class="operator">::</span>createUndoView() { undoView <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qundoview.html">QUndoView</a></span>(undoStack); undoView<span class="operator">-</span><span class="operator">></span>setWindowTitle(tr(<span class="string">"Command List"</span>)); undoView<span class="operator">-</span><span class="operator">></span>show(); undoView<span class="operator">-</span><span class="operator">></span>setAttribute(<span class="type"><a href="../qtcore/qt.html">Qt</a></span><span class="operator">::</span>WA_QuitOnClose<span class="operator">,</span> <span class="keyword">false</span>); } <span class="type">void</span> MainWindow<span class="operator">::</span>createActions() { deleteAction <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(tr(<span class="string">"&Delete Item"</span>)<span class="operator">,</span> <span class="keyword">this</span>); deleteAction<span class="operator">-</span><span class="operator">></span>setShortcut(tr(<span class="string">"Del"</span>)); connect(deleteAction<span class="operator">,</span> SIGNAL(triggered())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(deleteItem())); addBoxAction <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(tr(<span class="string">"Add &Box"</span>)<span class="operator">,</span> <span class="keyword">this</span>); addBoxAction<span class="operator">-</span><span class="operator">></span>setShortcut(tr(<span class="string">"Ctrl+O"</span>)); connect(addBoxAction<span class="operator">,</span> SIGNAL(triggered())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(addBox())); addTriangleAction <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(tr(<span class="string">"Add &Triangle"</span>)<span class="operator">,</span> <span class="keyword">this</span>); addTriangleAction<span class="operator">-</span><span class="operator">></span>setShortcut(tr(<span class="string">"Ctrl+T"</span>)); connect(addTriangleAction<span class="operator">,</span> SIGNAL(triggered())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(addTriangle())); undoAction <span class="operator">=</span> undoStack<span class="operator">-</span><span class="operator">></span>createUndoAction(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"&Undo"</span>)); undoAction<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Undo); redoAction <span class="operator">=</span> undoStack<span class="operator">-</span><span class="operator">></span>createRedoAction(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"&Redo"</span>)); redoAction<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Redo); exitAction <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(tr(<span class="string">"E&xit"</span>)<span class="operator">,</span> <span class="keyword">this</span>); exitAction<span class="operator">-</span><span class="operator">></span>setShortcuts(<span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">::</span>Quit); connect(exitAction<span class="operator">,</span> SIGNAL(triggered())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(close())); aboutAction <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qaction.html">QAction</a></span>(tr(<span class="string">"&About"</span>)<span class="operator">,</span> <span class="keyword">this</span>); <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator"><</span><span class="type"><a href="../qtgui/qkeysequence.html">QKeySequence</a></span><span class="operator">></span> aboutShortcuts; aboutShortcuts <span class="operator"><</span><span class="operator"><</span> tr(<span class="string">"Ctrl+A"</span>) <span class="operator"><</span><span class="operator"><</span> tr(<span class="string">"Ctrl+B"</span>); aboutAction<span class="operator">-</span><span class="operator">></span>setShortcuts(aboutShortcuts); connect(aboutAction<span class="operator">,</span> SIGNAL(triggered())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(about())); } <span class="type">void</span> MainWindow<span class="operator">::</span>createMenus() { fileMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&File"</span>)); fileMenu<span class="operator">-</span><span class="operator">></span>addAction(exitAction); editMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&Edit"</span>)); editMenu<span class="operator">-</span><span class="operator">></span>addAction(undoAction); editMenu<span class="operator">-</span><span class="operator">></span>addAction(redoAction); editMenu<span class="operator">-</span><span class="operator">></span>addSeparator(); editMenu<span class="operator">-</span><span class="operator">></span>addAction(deleteAction); connect(editMenu<span class="operator">,</span> SIGNAL(aboutToShow())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(itemMenuAboutToShow())); connect(editMenu<span class="operator">,</span> SIGNAL(aboutToHide())<span class="operator">,</span> <span class="keyword">this</span><span class="operator">,</span> SLOT(itemMenuAboutToHide())); itemMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&Item"</span>)); itemMenu<span class="operator">-</span><span class="operator">></span>addAction(addBoxAction); itemMenu<span class="operator">-</span><span class="operator">></span>addAction(addTriangleAction); helpMenu <span class="operator">=</span> menuBar()<span class="operator">-</span><span class="operator">></span>addMenu(tr(<span class="string">"&About"</span>)); helpMenu<span class="operator">-</span><span class="operator">></span>addAction(aboutAction); } <span class="type">void</span> MainWindow<span class="operator">::</span>itemMoved(DiagramItem <span class="operator">*</span>movedItem<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> <span class="operator">&</span>oldPosition) { undoStack<span class="operator">-</span><span class="operator">></span>push(<span class="keyword">new</span> MoveCommand(movedItem<span class="operator">,</span> oldPosition)); } <span class="type">void</span> MainWindow<span class="operator">::</span>deleteItem() { <span class="keyword">if</span> (diagramScene<span class="operator">-</span><span class="operator">></span>selectedItems()<span class="operator">.</span>isEmpty()) <span class="keyword">return</span>; <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>deleteCommand <span class="operator">=</span> <span class="keyword">new</span> DeleteCommand(diagramScene); undoStack<span class="operator">-</span><span class="operator">></span>push(deleteCommand); } <span class="type">void</span> MainWindow<span class="operator">::</span>itemMenuAboutToHide() { deleteAction<span class="operator">-</span><span class="operator">></span>setEnabled(<span class="keyword">true</span>); } <span class="type">void</span> MainWindow<span class="operator">::</span>itemMenuAboutToShow() { deleteAction<span class="operator">-</span><span class="operator">></span>setEnabled(<span class="operator">!</span>diagramScene<span class="operator">-</span><span class="operator">></span>selectedItems()<span class="operator">.</span>isEmpty()); } <span class="type">void</span> MainWindow<span class="operator">::</span>addBox() { <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>addCommand <span class="operator">=</span> <span class="keyword">new</span> AddCommand(DiagramItem<span class="operator">::</span>Box<span class="operator">,</span> diagramScene); undoStack<span class="operator">-</span><span class="operator">></span>push(addCommand); } <span class="type">void</span> MainWindow<span class="operator">::</span>addTriangle() { <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>addCommand <span class="operator">=</span> <span class="keyword">new</span> AddCommand(DiagramItem<span class="operator">::</span>Triangle<span class="operator">,</span> diagramScene); undoStack<span class="operator">-</span><span class="operator">></span>push(addCommand); } <span class="type">void</span> MainWindow<span class="operator">::</span>about() { <span class="type"><a href="qmessagebox.html">QMessageBox</a></span><span class="operator">::</span>about(<span class="keyword">this</span><span class="operator">,</span> tr(<span class="string">"About Undo"</span>)<span class="operator">,</span> tr(<span class="string">"The <b>Undo</b> example demonstrates how to "</span> <span class="string">"use Qt's undo framework."</span>)); } </pre> </div> <!-- @@@tools/undoframework/mainwindow.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>