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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">model.cpp Example File</h1> <span class="small-subtitle">demos/interview/model.cpp</span> <!-- $$$demos/interview/model.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 demonstration applications of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:LGPL$ ** 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 http://www.qt.io/terms-conditions. For further ** information use the contact form at http://www.qt.io/contact-us. ** ** GNU Lesser General Public License Usage ** Alternatively, this file may be used under the terms of the GNU Lesser ** General Public License version 2.1 or version 3 as published by the Free ** Software Foundation and appearing in the file LICENSE.LGPLv21 and ** LICENSE.LGPLv3 included in the packaging of this file. Please review the ** following information to ensure the GNU Lesser General Public License ** requirements will be met: https://www.gnu.org/licenses/lgpl.html and ** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. ** ** As a special exception, The Qt Company gives you certain additional ** rights. These rights are described in The Qt Company LGPL Exception ** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3.0 as published by the Free Software ** Foundation and appearing in the file LICENSE.GPL included in the ** packaging of this file. Please review the following information to ** ensure the GNU General Public License version 3.0 requirements will be ** met: http://www.gnu.org/copyleft/gpl.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "model.h"</span> <span class="preprocessor">#include <QIcon></span> <span class="preprocessor">#include <QPixmap></span> Model<span class="operator">::</span>Model(<span class="type">int</span> rows<span class="operator">,</span> <span class="type">int</span> columns<span class="operator">,</span> <span class="type"><a href="qobject.html">QObject</a></span> <span class="operator">*</span>parent) : <span class="type"><a href="qabstractitemmodel.html">QAbstractItemModel</a></span>(parent)<span class="operator">,</span> services(<span class="type"><a href="qpixmap.html">QPixmap</a></span>(<span class="string">":/images/services.png"</span>))<span class="operator">,</span> rc(rows)<span class="operator">,</span> cc(columns)<span class="operator">,</span> tree(<span class="keyword">new</span> <span class="type"><a href="qvector.html">QVector</a></span><span class="operator"><</span>Node<span class="operator">></span>(rows<span class="operator">,</span> Node(<span class="number">0</span>))) { } Model<span class="operator">::</span><span class="operator">~</span>Model() { <span class="keyword">delete</span> tree; } <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> Model<span class="operator">::</span>index(<span class="type">int</span> row<span class="operator">,</span> <span class="type">int</span> column<span class="operator">,</span> <span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>parent) <span class="keyword">const</span> { <span class="keyword">if</span> (row <span class="operator"><</span> rc <span class="operator">&</span><span class="operator">&</span> row <span class="operator">></span><span class="operator">=</span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> column <span class="operator"><</span> cc <span class="operator">&</span><span class="operator">&</span> column <span class="operator">></span><span class="operator">=</span> <span class="number">0</span>) { Node <span class="operator">*</span>p <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span>Node<span class="operator">*</span><span class="operator">></span>(parent<span class="operator">.</span>internalPointer()); Node <span class="operator">*</span>n <span class="operator">=</span> node(row<span class="operator">,</span> p); <span class="keyword">if</span> (n) <span class="keyword">return</span> createIndex(row<span class="operator">,</span> column<span class="operator">,</span> n); } <span class="keyword">return</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span>(); } <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> Model<span class="operator">::</span>parent(<span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>child) <span class="keyword">const</span> { <span class="keyword">if</span> (child<span class="operator">.</span>isValid()) { Node <span class="operator">*</span>n <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span>Node<span class="operator">*</span><span class="operator">></span>(child<span class="operator">.</span>internalPointer()); Node <span class="operator">*</span>p <span class="operator">=</span> parent(n); <span class="keyword">if</span> (p) <span class="keyword">return</span> createIndex(row(p)<span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> p); } <span class="keyword">return</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span>(); } <span class="type">int</span> Model<span class="operator">::</span>rowCount(<span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>parent) <span class="keyword">const</span> { <span class="keyword">return</span> (parent<span class="operator">.</span>isValid() <span class="operator">&</span><span class="operator">&</span> parent<span class="operator">.</span>column() <span class="operator">!</span><span class="operator">=</span> <span class="number">0</span>) <span class="operator">?</span> <span class="number">0</span> : rc; } <span class="type">int</span> Model<span class="operator">::</span>columnCount(<span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>parent) <span class="keyword">const</span> { Q_UNUSED(parent); <span class="keyword">return</span> cc; } <span class="type"><a href="qvariant.html">QVariant</a></span> Model<span class="operator">::</span>data(<span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>index<span class="operator">,</span> <span class="type">int</span> role) <span class="keyword">const</span> { <span class="keyword">if</span> (<span class="operator">!</span>index<span class="operator">.</span>isValid()) <span class="keyword">return</span> <span class="type"><a href="qvariant.html">QVariant</a></span>(); <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>DisplayRole) <span class="keyword">return</span> <span class="string">"Item "</span> <span class="operator">+</span> <span class="type"><a href="qstring.html">QString</a></span><span class="operator">::</span>number(index<span class="operator">.</span>row()) <span class="operator">+</span> <span class="string">":"</span> <span class="operator">+</span> <span class="type"><a href="qstring.html">QString</a></span><span class="operator">::</span>number(index<span class="operator">.</span>column()); <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>DecorationRole) { <span class="keyword">if</span> (index<span class="operator">.</span>column() <span class="operator">=</span><span class="operator">=</span> <span class="number">0</span>) <span class="keyword">return</span> iconProvider<span class="operator">.</span>icon(<span class="type"><a href="qfileiconprovider.html">QFileIconProvider</a></span><span class="operator">::</span>Folder); <span class="keyword">return</span> iconProvider<span class="operator">.</span>icon(<span class="type"><a href="qfileiconprovider.html">QFileIconProvider</a></span><span class="operator">::</span>File); } <span class="keyword">return</span> <span class="type"><a href="qvariant.html">QVariant</a></span>(); } <span class="type"><a href="qvariant.html">QVariant</a></span> Model<span class="operator">::</span>headerData(<span class="type">int</span> section<span class="operator">,</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>Orientation orientation<span class="operator">,</span> <span class="type">int</span> role) <span class="keyword">const</span> { <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>DisplayRole) <span class="keyword">return</span> <span class="type"><a href="qstring.html">QString</a></span><span class="operator">::</span>number(section); <span class="keyword">if</span> (role <span class="operator">=</span><span class="operator">=</span> <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>DecorationRole) <span class="keyword">return</span> <span class="type"><a href="qvariant.html">QVariant</a></span><span class="operator">::</span>fromValue(services); <span class="keyword">return</span> <span class="type"><a href="qabstractitemmodel.html">QAbstractItemModel</a></span><span class="operator">::</span>headerData(section<span class="operator">,</span> orientation<span class="operator">,</span> role); } <span class="type">bool</span> Model<span class="operator">::</span>hasChildren(<span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>parent) <span class="keyword">const</span> { <span class="keyword">if</span> (parent<span class="operator">.</span>isValid() <span class="operator">&</span><span class="operator">&</span> parent<span class="operator">.</span>column() <span class="operator">!</span><span class="operator">=</span> <span class="number">0</span>) <span class="keyword">return</span> <span class="keyword">false</span>; <span class="keyword">return</span> rc <span class="operator">></span> <span class="number">0</span> <span class="operator">&</span><span class="operator">&</span> cc <span class="operator">></span> <span class="number">0</span>; } <span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>ItemFlags Model<span class="operator">::</span>flags(<span class="keyword">const</span> <span class="type"><a href="qmodelindex.html">QModelIndex</a></span> <span class="operator">&</span>index) <span class="keyword">const</span> { <span class="keyword">if</span> (<span class="operator">!</span>index<span class="operator">.</span>isValid()) <span class="keyword">return</span> <span class="number">0</span>; <span class="keyword">return</span> (<span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>ItemIsDragEnabled<span class="operator">|</span><span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>ItemIsSelectable<span class="operator">|</span><span class="type"><a href="qt.html">Qt</a></span><span class="operator">::</span>ItemIsEnabled); } Model<span class="operator">::</span>Node <span class="operator">*</span>Model<span class="operator">::</span>node(<span class="type">int</span> row<span class="operator">,</span> Node <span class="operator">*</span>parent) <span class="keyword">const</span> { <span class="keyword">if</span> (parent <span class="operator">&</span><span class="operator">&</span> <span class="operator">!</span>parent<span class="operator">-</span><span class="operator">></span>children) parent<span class="operator">-</span><span class="operator">></span>children <span class="operator">=</span> <span class="keyword">new</span> <span class="type"><a href="qvector.html">QVector</a></span><span class="operator"><</span>Node<span class="operator">></span>(rc<span class="operator">,</span> Node(parent)); <span class="type"><a href="qvector.html">QVector</a></span><span class="operator"><</span>Node<span class="operator">></span> <span class="operator">*</span>v <span class="operator">=</span> parent <span class="operator">?</span> parent<span class="operator">-</span><span class="operator">></span>children : tree; <span class="keyword">return</span> <span class="keyword">const_cast</span><span class="operator"><</span>Node<span class="operator">*</span><span class="operator">></span>(<span class="operator">&</span>(v<span class="operator">-</span><span class="operator">></span>at(row))); } Model<span class="operator">::</span>Node <span class="operator">*</span>Model<span class="operator">::</span>parent(Node <span class="operator">*</span>child) <span class="keyword">const</span> { <span class="keyword">return</span> child <span class="operator">?</span> child<span class="operator">-</span><span class="operator">></span>parent : <span class="number">0</span>; } <span class="type">int</span> Model<span class="operator">::</span>row(Node <span class="operator">*</span>node) <span class="keyword">const</span> { <span class="keyword">const</span> Node <span class="operator">*</span>first <span class="operator">=</span> node<span class="operator">-</span><span class="operator">></span>parent <span class="operator">?</span> <span class="operator">&</span>(node<span class="operator">-</span><span class="operator">></span>parent<span class="operator">-</span><span class="operator">></span>children<span class="operator">-</span><span class="operator">></span>at(<span class="number">0</span>)) : <span class="operator">&</span>(tree<span class="operator">-</span><span class="operator">></span>at(<span class="number">0</span>)); <span class="keyword">return</span> (node <span class="operator">-</span> first); }</pre> </div> <!-- @@@demos/interview/model.cpp --> </div> </div> </div> <div class="ft"> <span></span> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2015 The Qt Company Ltd. 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