<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en_US" lang="en_US"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>Qt 4.8: graphwidget.cpp Example File (graphicsview/elasticnodes/graphwidget.cpp)</title> <link rel="stylesheet" type="text/css" href="style/style.css" /> <script src="scripts/jquery.js" type="text/javascript"></script> <script src="scripts/functions.js" type="text/javascript"></script> <link rel="stylesheet" type="text/css" href="style/superfish.css" /> <link rel="stylesheet" type="text/css" href="style/narrow.css" /> <!--[if IE]> <meta name="MSSmartTagsPreventParsing" content="true"> <meta http-equiv="imagetoolbar" content="no"> <![endif]--> <!--[if lt IE 7]> <link rel="stylesheet" type="text/css" href="style/style_ie6.css"> <![endif]--> <!--[if IE 7]> <link rel="stylesheet" type="text/css" href="style/style_ie7.css"> <![endif]--> <!--[if IE 8]> <link rel="stylesheet" type="text/css" href="style/style_ie8.css"> <![endif]--> <script src="scripts/superfish.js" type="text/javascript"></script> <script src="scripts/narrow.js" type="text/javascript"></script> </head> <body class="" onload="CheckEmptyAndLoadList();"> <div class="header" id="qtdocheader"> <div class="content"> <div id="nav-logo"> <a href="index.html">Home</a></div> <a href="index.html" class="qtref"><span>Qt Reference Documentation</span></a> <div id="narrowsearch"></div> <div id="nav-topright"> <ul> <li class="nav-topright-home"><a href="http://qt.digia.com/">Qt HOME</a></li> <li class="nav-topright-dev"><a href="http://qt-project.org/">DEV</a></li> <li class="nav-topright-doc nav-topright-doc-active"><a href="http://qt-project.org/doc/"> DOC</a></li> <li class="nav-topright-blog"><a href="http://blog.qt.digia.com/">BLOG</a></li> </ul> </div> <div id="shortCut"> <ul> <li class="shortCut-topleft-inactive"><span><a href="index.html">Qt 4.8</a></span></li> <li class="shortCut-topleft-active"><a href="http://qt-project.org/doc/">ALL VERSIONS </a></li> </ul> </div> <ul class="sf-menu" id="narrowmenu"> <li><a href="#">API Lookup</a> <ul> <li><a href="classes.html">Class index</a></li> <li><a href="functions.html">Function index</a></li> <li><a href="modules.html">Modules</a></li> <li><a href="namespaces.html">Namespaces</a></li> <li><a href="qtglobal.html">Global Declarations</a></li> <li><a href="qdeclarativeelements.html">QML elements</a></li> </ul> </li> <li><a href="#">Qt Topics</a> <ul> <li><a href="qt-basic-concepts.html">Programming with Qt</a></li> <li><a href="qtquick.html">Device UIs & Qt Quick</a></li> <li><a href="qt-gui-concepts.html">UI Design with Qt</a></li> <li><a href="supported-platforms.html">Supported Platforms</a></li> <li><a href="technology-apis.html">Qt and Key Technologies</a></li> <li><a href="best-practices.html">How-To's and Best Practices</a></li> </ul> </li> <li><a href="#">Examples</a> <ul> <li><a href="all-examples.html">Examples</a></li> <li><a href="tutorials.html">Tutorials</a></li> <li><a href="demos.html">Demos</a></li> <li><a href="qdeclarativeexamples.html">QML Examples</a></li> </ul> </li> </ul> </div> </div> <div class="wrapper"> <div class="hd"> <span></span> </div> <div class="bd group"> <div class="sidebar"> <div class="searchlabel"> Search index:</div> <div class="search" id="sidebarsearch"> <form id="qtdocsearch" action="" onsubmit="return false;"> <fieldset> <input type="text" name="searchstring" id="pageType" value="" /> <div id="resultdialog"> <a href="#" id="resultclose">Close</a> <p id="resultlinks" class="all"><a href="#" id="showallresults">All</a> | <a href="#" id="showapiresults">API</a> | <a href="#" id="showarticleresults">Articles</a> | <a href="#" id="showexampleresults">Examples</a></p> <p id="searchcount" class="all"><span id="resultcount"></span><span id="apicount"></span><span id="articlecount"></span><span id="examplecount"></span> results:</p> <ul id="resultlist" class="all"> </ul> </div> </fieldset> </form> </div> <div class="box first bottombar" id="lookup"> <h2 title="API Lookup"><span></span> API Lookup</h2> <div id="list001" class="list"> <ul id="ul001" > <li class="defaultLink"><a href="classes.html">Class index</a></li> <li class="defaultLink"><a href="functions.html">Function index</a></li> <li class="defaultLink"><a href="modules.html">Modules</a></li> <li class="defaultLink"><a href="namespaces.html">Namespaces</a></li> <li class="defaultLink"><a href="qtglobal.html">Global Declarations</a></li> <li class="defaultLink"><a href="qdeclarativeelements.html">QML elements</a></li> </ul> </div> </div> <div class="box bottombar" id="topics"> <h2 title="Qt Topics"><span></span> Qt Topics</h2> <div id="list002" class="list"> <ul id="ul002" > <li class="defaultLink"><a href="qt-basic-concepts.html">Programming with Qt</a></li> <li class="defaultLink"><a href="qtquick.html">Device UIs & Qt Quick</a></li> <li class="defaultLink"><a href="qt-gui-concepts.html">UI Design with Qt</a></li> <li class="defaultLink"><a href="supported-platforms.html">Supported Platforms</a></li> <li class="defaultLink"><a href="technology-apis.html">Qt and Key Technologies</a></li> <li class="defaultLink"><a href="best-practices.html">How-To's and Best Practices</a></li> </ul> </div> </div> <div class="box" id="examples"> <h2 title="Examples"><span></span> Examples</h2> <div id="list003" class="list"> <ul id="ul003"> <li class="defaultLink"><a href="all-examples.html">Examples</a></li> <li class="defaultLink"><a href="tutorials.html">Tutorials</a></li> <li class="defaultLink"><a href="demos.html">Demos</a></li> <li class="defaultLink"><a href="qdeclarativeexamples.html">QML Examples</a></li> </ul> </div> </div> </div> <div class="wrap"> <div class="toolbar"> <div class="breadcrumb toolblock"> <ul> <li class="first"><a href="index.html">Home</a></li> <!-- Breadcrumbs go here --> </ul> </div> <div class="toolbuttons toolblock"> <ul> <li id="smallA" class="t_button">A</li> <li id="medA" class="t_button active">A</li> <li id="bigA" class="t_button">A</li> <li id="print" class="t_button"><a href="javascript:this.print();"> <span>Print</span></a></li> </ul> </div> </div> <div class="content mainContent"> <h1 class="title">graphwidget.cpp Example File</h1> <span class="small-subtitle">graphicsview/elasticnodes/graphwidget.cpp</span> <!-- $$$graphicsview/elasticnodes/graphwidget.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2015 The Qt Company Ltd. ** Contact: http://www.qt.io/licensing/ ** ** This file is part of the examples of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:BSD$ ** 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 "graphwidget.h"</span> <span class="preprocessor">#include "edge.h"</span> <span class="preprocessor">#include "node.h"</span> <span class="preprocessor">#include <QtGui></span> <span class="preprocessor">#include <math.h></span> GraphWidget<span class="operator">::</span>GraphWidget(<span class="type"><a href="qwidget.html">QWidget</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span>(parent)<span class="operator">,</span> timerId(<span class="number">0</span>) { <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span> <span class="operator">*</span>scene <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span>(<span class="keyword">this</span>); scene<span class="operator">-</span><span class="operator">></span>setItemIndexMethod(<span class="type"><a href="qgraphicsscene.html">QGraphicsScene</a></span><span class="operator">::</span>NoIndex); scene<span class="operator">-</span><span class="operator">></span>setSceneRect(<span class="operator">-</span><span class="number">200</span><span class="operator">,</span> <span class="operator">-</span><span class="number">200</span><span class="operator">,</span> <span class="number">400</span><span class="operator">,</span> <span class="number">400</span>); setScene(scene); setCacheMode(CacheBackground); setViewportUpdateMode(BoundingRectViewportUpdate); setRenderHint(<span class="type"><a href="qpainter.html">QPainter</a></span><span class="operator">::</span>Antialiasing); setTransformationAnchor(AnchorUnderMouse); scale(<span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span>(<span class="number">0.8</span>)<span class="operator">,</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span>(<span class="number">0.8</span>)); setMinimumSize(<span class="number">400</span><span class="operator">,</span> <span class="number">400</span>); setWindowTitle(tr(<span class="string">"Elastic Nodes"</span>)); Node <span class="operator">*</span>node1 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node2 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node3 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node4 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); centerNode <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node6 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node7 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node8 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); Node <span class="operator">*</span>node9 <span class="operator">=</span> <span class="keyword">new</span> Node(<span class="keyword">this</span>); scene<span class="operator">-</span><span class="operator">></span>addItem(node1); scene<span class="operator">-</span><span class="operator">></span>addItem(node2); scene<span class="operator">-</span><span class="operator">></span>addItem(node3); scene<span class="operator">-</span><span class="operator">></span>addItem(node4); scene<span class="operator">-</span><span class="operator">></span>addItem(centerNode); scene<span class="operator">-</span><span class="operator">></span>addItem(node6); scene<span class="operator">-</span><span class="operator">></span>addItem(node7); scene<span class="operator">-</span><span class="operator">></span>addItem(node8); scene<span class="operator">-</span><span class="operator">></span>addItem(node9); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node1<span class="operator">,</span> node2)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node2<span class="operator">,</span> node3)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node2<span class="operator">,</span> centerNode)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node3<span class="operator">,</span> node6)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node4<span class="operator">,</span> node1)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node4<span class="operator">,</span> centerNode)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(centerNode<span class="operator">,</span> node6)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(centerNode<span class="operator">,</span> node8)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node6<span class="operator">,</span> node9)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node7<span class="operator">,</span> node4)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node8<span class="operator">,</span> node7)); scene<span class="operator">-</span><span class="operator">></span>addItem(<span class="keyword">new</span> Edge(node9<span class="operator">,</span> node8)); node1<span class="operator">-</span><span class="operator">></span>setPos(<span class="operator">-</span><span class="number">50</span><span class="operator">,</span> <span class="operator">-</span><span class="number">50</span>); node2<span class="operator">-</span><span class="operator">></span>setPos(<span class="number">0</span><span class="operator">,</span> <span class="operator">-</span><span class="number">50</span>); node3<span class="operator">-</span><span class="operator">></span>setPos(<span class="number">50</span><span class="operator">,</span> <span class="operator">-</span><span class="number">50</span>); node4<span class="operator">-</span><span class="operator">></span>setPos(<span class="operator">-</span><span class="number">50</span><span class="operator">,</span> <span class="number">0</span>); centerNode<span class="operator">-</span><span class="operator">></span>setPos(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span>); node6<span class="operator">-</span><span class="operator">></span>setPos(<span class="number">50</span><span class="operator">,</span> <span class="number">0</span>); node7<span class="operator">-</span><span class="operator">></span>setPos(<span class="operator">-</span><span class="number">50</span><span class="operator">,</span> <span class="number">50</span>); node8<span class="operator">-</span><span class="operator">></span>setPos(<span class="number">0</span><span class="operator">,</span> <span class="number">50</span>); node9<span class="operator">-</span><span class="operator">></span>setPos(<span class="number">50</span><span class="operator">,</span> <span class="number">50</span>); } <span class="type">void</span> GraphWidget<span class="operator">::</span>itemMoved() { <span class="keyword">if</span> (<span class="operator">!</span>timerId) timerId <span class="operator">=</span> startTimer(<span class="number">1000</span> <span class="operator">/</span> <span class="number">25</span>); } <span class="type">void</span> GraphWidget<span class="operator">::</span>keyPressEvent(<span class="type"><a href="qkeyevent.html">QKeyEvent</a></span> <span class="operator">*</span>event) { <span class="keyword">switch</span> (event<span class="operator">-</span><span class="operator">></span>key()) { <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Up: centerNode<span class="operator">-</span><span class="operator">></span>moveBy(<span class="number">0</span><span class="operator">,</span> <span class="operator">-</span><span class="number">20</span>); <span class="keyword">break</span>; <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Down: centerNode<span class="operator">-</span><span class="operator">></span>moveBy(<span class="number">0</span><span class="operator">,</span> <span class="number">20</span>); <span class="keyword">break</span>; <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Left: centerNode<span class="operator">-</span><span class="operator">></span>moveBy(<span class="operator">-</span><span class="number">20</span><span class="operator">,</span> <span class="number">0</span>); <span class="keyword">break</span>; <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Right: centerNode<span class="operator">-</span><span class="operator">></span>moveBy(<span class="number">20</span><span class="operator">,</span> <span class="number">0</span>); <span class="keyword">break</span>; <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Plus: zoomIn(); <span class="keyword">break</span>; <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Minus: zoomOut(); <span class="keyword">break</span>; <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Space: <span class="keyword">case</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Key_Enter: shuffle(); <span class="keyword">break</span>; <span class="keyword">default</span>: <span class="type"><a href="qgraphicsview.html">QGraphicsView</a></span><span class="operator">::</span>keyPressEvent(event); } } <span class="type">void</span> GraphWidget<span class="operator">::</span>timerEvent(<span class="type"><a href="qtimerevent.html">QTimerEvent</a></span> <span class="operator">*</span>event) { Q_UNUSED(event); <span class="type"><a href="qlist.html">QList</a></span><span class="operator"><</span>Node <span class="operator">*</span><span class="operator">></span> nodes; foreach (<span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span> <span class="operator">*</span>item<span class="operator">,</span> scene()<span class="operator">-</span><span class="operator">></span>items()) { <span class="keyword">if</span> (Node <span class="operator">*</span>node <span class="operator">=</span> qgraphicsitem_cast<span class="operator"><</span>Node <span class="operator">*</span><span class="operator">></span>(item)) nodes <span class="operator"><</span><span class="operator"><</span> node; } foreach (Node <span class="operator">*</span>node<span class="operator">,</span> nodes) node<span class="operator">-</span><span class="operator">></span>calculateForces(); <span class="type">bool</span> itemsMoved <span class="operator">=</span> <span class="keyword">false</span>; foreach (Node <span class="operator">*</span>node<span class="operator">,</span> nodes) { <span class="keyword">if</span> (node<span class="operator">-</span><span class="operator">></span>advance()) itemsMoved <span class="operator">=</span> <span class="keyword">true</span>; } <span class="keyword">if</span> (<span class="operator">!</span>itemsMoved) { killTimer(timerId); timerId <span class="operator">=</span> <span class="number">0</span>; } } <span class="type">void</span> GraphWidget<span class="operator">::</span>wheelEvent(<span class="type"><a href="qwheelevent.html">QWheelEvent</a></span> <span class="operator">*</span>event) { scaleView(pow((<span class="type">double</span>)<span class="number">2</span><span class="operator">,</span> <span class="operator">-</span>event<span class="operator">-</span><span class="operator">></span>delta() <span class="operator">/</span> <span class="number">240.0</span>)); } <span class="type">void</span> GraphWidget<span class="operator">::</span>drawBackground(<span class="type"><a href="qpainter.html">QPainter</a></span> <span class="operator">*</span>painter<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="qrectf.html">QRectF</a></span> <span class="operator">&</span>rect) { Q_UNUSED(rect); <span class="comment">// Shadow</span> <span class="type"><a href="qrectf.html">QRectF</a></span> sceneRect <span class="operator">=</span> <span class="keyword">this</span><span class="operator">-</span><span class="operator">></span>sceneRect(); <span class="type"><a href="qrectf.html">QRectF</a></span> rightShadow(sceneRect<span class="operator">.</span>right()<span class="operator">,</span> sceneRect<span class="operator">.</span>top() <span class="operator">+</span> <span class="number">5</span><span class="operator">,</span> <span class="number">5</span><span class="operator">,</span> sceneRect<span class="operator">.</span>height()); <span class="type"><a href="qrectf.html">QRectF</a></span> bottomShadow(sceneRect<span class="operator">.</span>left() <span class="operator">+</span> <span class="number">5</span><span class="operator">,</span> sceneRect<span class="operator">.</span>bottom()<span class="operator">,</span> sceneRect<span class="operator">.</span>width()<span class="operator">,</span> <span class="number">5</span>); <span class="keyword">if</span> (rightShadow<span class="operator">.</span>intersects(rect) <span class="operator">|</span><span class="operator">|</span> rightShadow<span class="operator">.</span>contains(rect)) painter<span class="operator">-</span><span class="operator">></span>fillRect(rightShadow<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>darkGray); <span class="keyword">if</span> (bottomShadow<span class="operator">.</span>intersects(rect) <span class="operator">|</span><span class="operator">|</span> bottomShadow<span class="operator">.</span>contains(rect)) painter<span class="operator">-</span><span class="operator">></span>fillRect(bottomShadow<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>darkGray); <span class="comment">// Fill</span> <span class="type"><a href="qlineargradient.html">QLinearGradient</a></span> gradient(sceneRect<span class="operator">.</span>topLeft()<span class="operator">,</span> sceneRect<span class="operator">.</span>bottomRight()); gradient<span class="operator">.</span>setColorAt(<span class="number">0</span><span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>white); gradient<span class="operator">.</span>setColorAt(<span class="number">1</span><span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>lightGray); painter<span class="operator">-</span><span class="operator">></span>fillRect(rect<span class="operator">.</span>intersect(sceneRect)<span class="operator">,</span> gradient); painter<span class="operator">-</span><span class="operator">></span>setBrush(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>NoBrush); painter<span class="operator">-</span><span class="operator">></span>drawRect(sceneRect); <span class="preprocessor">#if !defined(Q_OS_SYMBIAN) && !defined(Q_WS_MAEMO_5)</span> <span class="comment">// Text</span> <span class="type"><a href="qrectf.html">QRectF</a></span> textRect(sceneRect<span class="operator">.</span>left() <span class="operator">+</span> <span class="number">4</span><span class="operator">,</span> sceneRect<span class="operator">.</span>top() <span class="operator">+</span> <span class="number">4</span><span class="operator">,</span> sceneRect<span class="operator">.</span>width() <span class="operator">-</span> <span class="number">4</span><span class="operator">,</span> sceneRect<span class="operator">.</span>height() <span class="operator">-</span> <span class="number">4</span>); <span class="type"><a href="qstring.html">QString</a></span> message(tr(<span class="string">"Click and drag the nodes around, and zoom with the mouse "</span> <span class="string">"wheel or the '+' and '-' keys"</span>)); <span class="type"><a href="qfont.html">QFont</a></span> font <span class="operator">=</span> painter<span class="operator">-</span><span class="operator">></span>font(); font<span class="operator">.</span>setBold(<span class="keyword">true</span>); font<span class="operator">.</span>setPointSize(<span class="number">14</span>); painter<span class="operator">-</span><span class="operator">></span>setFont(font); painter<span class="operator">-</span><span class="operator">></span>setPen(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>lightGray); painter<span class="operator">-</span><span class="operator">></span>drawText(textRect<span class="operator">.</span>translated(<span class="number">2</span><span class="operator">,</span> <span class="number">2</span>)<span class="operator">,</span> message); painter<span class="operator">-</span><span class="operator">></span>setPen(<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>black); painter<span class="operator">-</span><span class="operator">></span>drawText(textRect<span class="operator">,</span> message); <span class="preprocessor">#endif</span> } <span class="type">void</span> GraphWidget<span class="operator">::</span>scaleView(<span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> scaleFactor) { <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span> factor <span class="operator">=</span> transform()<span class="operator">.</span>scale(scaleFactor<span class="operator">,</span> scaleFactor)<span class="operator">.</span>mapRect(<span class="type"><a href="qrectf.html">QRectF</a></span>(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> <span class="number">1</span><span class="operator">,</span> <span class="number">1</span>))<span class="operator">.</span>width(); <span class="keyword">if</span> (factor <span class="operator"><</span> <span class="number">0.07</span> <span class="operator">|</span><span class="operator">|</span> factor <span class="operator">></span> <span class="number">100</span>) <span class="keyword">return</span>; scale(scaleFactor<span class="operator">,</span> scaleFactor); } <span class="type">void</span> GraphWidget<span class="operator">::</span>shuffle() { foreach (<span class="type"><a href="qgraphicsitem.html">QGraphicsItem</a></span> <span class="operator">*</span>item<span class="operator">,</span> scene()<span class="operator">-</span><span class="operator">></span>items()) { <span class="keyword">if</span> (qgraphicsitem_cast<span class="operator"><</span>Node <span class="operator">*</span><span class="operator">></span>(item)) item<span class="operator">-</span><span class="operator">></span>setPos(<span class="operator">-</span><span class="number">150</span> <span class="operator">+</span> qrand() <span class="operator">%</span> <span class="number">300</span><span class="operator">,</span> <span class="operator">-</span><span class="number">150</span> <span class="operator">+</span> qrand() <span class="operator">%</span> <span class="number">300</span>); } } <span class="type">void</span> GraphWidget<span class="operator">::</span>zoomIn() { scaleView(<span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span>(<span class="number">1.2</span>)); } <span class="type">void</span> GraphWidget<span class="operator">::</span>zoomOut() { scaleView(<span class="number">1</span> <span class="operator">/</span> <span class="type"><a href="qtglobal.html#qreal-typedef">qreal</a></span>(<span class="number">1.2</span>)); }</pre> </div> <!-- @@@graphicsview/elasticnodes/graphwidget.cpp --> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. Documentation contributions included herein are the copyrights of their respective owners.</p> <br /> <p> 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.</p> <p> Documentation sources may be obtained from <a href="http://www.qt-project.org"> www.qt-project.org</a>.</p> <br /> <p> 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. <a title="Privacy Policy" href="http://en.gitorious.org/privacy_policy/">Privacy Policy</a></p> </div> <script src="scripts/functions.js" type="text/javascript"></script> </body> </html>