<?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>commands.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-undoframework-example.html">Undo Framework Example</a></td><td >commands.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">commands.cpp Example File</h1> <span class="subtitle">tools/undoframework/commands.cpp</span> <!-- $$$tools/undoframework/commands.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 "commands.h"</span> <span class="preprocessor">#include "diagramitem.h"</span> MoveCommand<span class="operator">::</span>MoveCommand(DiagramItem <span class="operator">*</span>diagramItem<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> <span class="operator">&</span>oldPos<span class="operator">,</span> <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qundocommand.html">QUndoCommand</a></span>(parent) { myDiagramItem <span class="operator">=</span> diagramItem; newPos <span class="operator">=</span> diagramItem<span class="operator">-</span><span class="operator">></span>pos(); myOldPos <span class="operator">=</span> oldPos; } bool MoveCommand<span class="operator">::</span>mergeWith(<span class="keyword">const</span> <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>command) { <span class="keyword">const</span> MoveCommand <span class="operator">*</span>moveCommand <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span><span class="keyword">const</span> MoveCommand <span class="operator">*</span><span class="operator">></span>(command); DiagramItem <span class="operator">*</span>item <span class="operator">=</span> moveCommand<span class="operator">-</span><span class="operator">></span>myDiagramItem; <span class="keyword">if</span> (myDiagramItem <span class="operator">!</span><span class="operator">=</span> item) <span class="keyword">return</span> <span class="keyword">false</span>; newPos <span class="operator">=</span> item<span class="operator">-</span><span class="operator">></span>pos(); setText(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>tr(<span class="string">"Move %1"</span>) <span class="operator">.</span>arg(createCommandString(myDiagramItem<span class="operator">,</span> newPos))); <span class="keyword">return</span> <span class="keyword">true</span>; } <span class="type">void</span> MoveCommand<span class="operator">::</span>undo() { myDiagramItem<span class="operator">-</span><span class="operator">></span>setPos(myOldPos); myDiagramItem<span class="operator">-</span><span class="operator">></span>scene()<span class="operator">-</span><span class="operator">></span>update(); setText(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>tr(<span class="string">"Move %1"</span>) <span class="operator">.</span>arg(createCommandString(myDiagramItem<span class="operator">,</span> newPos))); } <span class="type">void</span> MoveCommand<span class="operator">::</span>redo() { myDiagramItem<span class="operator">-</span><span class="operator">></span>setPos(newPos); setText(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>tr(<span class="string">"Move %1"</span>) <span class="operator">.</span>arg(createCommandString(myDiagramItem<span class="operator">,</span> newPos))); } DeleteCommand<span class="operator">::</span>DeleteCommand(<span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span> <span class="operator">*</span>scene<span class="operator">,</span> <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qundocommand.html">QUndoCommand</a></span>(parent) { myGraphicsScene <span class="operator">=</span> scene; <span class="type"><a href="../qtcore/qlist.html">QList</a></span><span class="operator"><</span><span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span> <span class="operator">*</span><span class="operator">></span> list <span class="operator">=</span> myGraphicsScene<span class="operator">-</span><span class="operator">></span>selectedItems(); list<span class="operator">.</span>first()<span class="operator">-</span><span class="operator">></span>setSelected(<span class="keyword">false</span>); myDiagramItem <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span>DiagramItem <span class="operator">*</span><span class="operator">></span>(list<span class="operator">.</span>first()); setText(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>tr(<span class="string">"Delete %1"</span>) <span class="operator">.</span>arg(createCommandString(myDiagramItem<span class="operator">,</span> myDiagramItem<span class="operator">-</span><span class="operator">></span>pos()))); } <span class="type">void</span> DeleteCommand<span class="operator">::</span>undo() { myGraphicsScene<span class="operator">-</span><span class="operator">></span>addItem(myDiagramItem); myGraphicsScene<span class="operator">-</span><span class="operator">></span>update(); } <span class="type">void</span> DeleteCommand<span class="operator">::</span>redo() { myGraphicsScene<span class="operator">-</span><span class="operator">></span>removeItem(myDiagramItem); } AddCommand<span class="operator">::</span>AddCommand(DiagramItem<span class="operator">::</span>DiagramType addType<span class="operator">,</span> <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span> <span class="operator">*</span>scene<span class="operator">,</span> <span class="type"><a href="qundocommand.html">QUndoCommand</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qundocommand.html">QUndoCommand</a></span>(parent) { <span class="keyword">static</span> <span class="type">int</span> itemCount <span class="operator">=</span> <span class="number">0</span>; myGraphicsScene <span class="operator">=</span> scene; myDiagramItem <span class="operator">=</span> <span class="keyword">new</span> DiagramItem(addType); initialPosition <span class="operator">=</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span>((itemCount <span class="operator">*</span> <span class="number">15</span>) <span class="operator">%</span> <span class="type">int</span>(scene<span class="operator">-</span><span class="operator">></span>width())<span class="operator">,</span> (itemCount <span class="operator">*</span> <span class="number">15</span>) <span class="operator">%</span> <span class="type">int</span>(scene<span class="operator">-</span><span class="operator">></span>height())); scene<span class="operator">-</span><span class="operator">></span>update(); <span class="operator">+</span><span class="operator">+</span>itemCount; setText(<span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>tr(<span class="string">"Add %1"</span>) <span class="operator">.</span>arg(createCommandString(myDiagramItem<span class="operator">,</span> initialPosition))); } AddCommand<span class="operator">::</span><span class="operator">~</span>AddCommand() { <span class="keyword">if</span> (<span class="operator">!</span>myDiagramItem<span class="operator">-</span><span class="operator">></span>scene()) <span class="keyword">delete</span> myDiagramItem; } <span class="type">void</span> AddCommand<span class="operator">::</span>undo() { myGraphicsScene<span class="operator">-</span><span class="operator">></span>removeItem(myDiagramItem); myGraphicsScene<span class="operator">-</span><span class="operator">></span>update(); } <span class="type">void</span> AddCommand<span class="operator">::</span>redo() { myGraphicsScene<span class="operator">-</span><span class="operator">></span>addItem(myDiagramItem); myDiagramItem<span class="operator">-</span><span class="operator">></span>setPos(initialPosition); myGraphicsScene<span class="operator">-</span><span class="operator">></span>clearSelection(); myGraphicsScene<span class="operator">-</span><span class="operator">></span>update(); } <span class="type"><a href="../qtcore/qstring.html">QString</a></span> createCommandString(DiagramItem <span class="operator">*</span>item<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="../qtcore/qpointf.html">QPointF</a></span> <span class="operator">&</span>pos) { <span class="keyword">return</span> <span class="type"><a href="../qtcore/qobject.html">QObject</a></span><span class="operator">::</span>tr(<span class="string">"%1 at (%2, %3)"</span>) <span class="operator">.</span>arg(item<span class="operator">-</span><span class="operator">></span>diagramType() <span class="operator">=</span><span class="operator">=</span> DiagramItem<span class="operator">::</span>Box <span class="operator">?</span> <span class="string">"Box"</span> : <span class="string">"Triangle"</span>) <span class="operator">.</span>arg(pos<span class="operator">.</span>x())<span class="operator">.</span>arg(pos<span class="operator">.</span>y()); } </pre> </div> <!-- @@@tools/undoframework/commands.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>