<?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>imageprovider.cpp Example File | Qt Quick 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="qtquick-index.html">Qt Quick</a></td><td ><a href="qtquick-imageprovider-example.html">C++ Extensions: Image Provider Example</a></td><td >imageprovider.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right"><a href="qtquick-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">imageprovider.cpp Example File</h1> <span class="subtitle">imageprovider/imageprovider.cpp</span> <!-- $$$imageprovider/imageprovider.cpp-description --> <div class="descr"> <a name="details"></a> <pre class="cpp"> <span class="comment">/**************************************************************************** ** ** Copyright (C) 2017 The Qt Company Ltd. ** Contact: https://www.qt.io/licensing/ ** ** This file is part of the demonstration applications 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 <qqmlextensionplugin.h></span> <span class="preprocessor">#include <qqmlengine.h></span> <span class="preprocessor">#include <qquickimageprovider.h></span> <span class="preprocessor">#include <QImage></span> <span class="preprocessor">#include <QPainter></span> <span class="keyword">class</span> ColorImageProvider : <span class="keyword">public</span> <span class="type"><a href="qquickimageprovider.html">QQuickImageProvider</a></span> { <span class="keyword">public</span>: ColorImageProvider() : <span class="type"><a href="qquickimageprovider.html">QQuickImageProvider</a></span>(<span class="type"><a href="qquickimageprovider.html">QQuickImageProvider</a></span><span class="operator">::</span>Pixmap) { } <span class="type">QPixmap</span> requestPixmap(<span class="keyword">const</span> <span class="type">QString</span> <span class="operator">&</span>id<span class="operator">,</span> <span class="type">QSize</span> <span class="operator">*</span>size<span class="operator">,</span> <span class="keyword">const</span> <span class="type">QSize</span> <span class="operator">&</span>requestedSize) override { <span class="type">int</span> width <span class="operator">=</span> <span class="number">100</span>; <span class="type">int</span> height <span class="operator">=</span> <span class="number">50</span>; <span class="keyword">if</span> (size) <span class="operator">*</span>size <span class="operator">=</span> <span class="type">QSize</span>(width<span class="operator">,</span> height); <span class="type">QPixmap</span> pixmap(requestedSize<span class="operator">.</span>width() <span class="operator">></span> <span class="number">0</span> <span class="operator">?</span> requestedSize<span class="operator">.</span>width() : width<span class="operator">,</span> requestedSize<span class="operator">.</span>height() <span class="operator">></span> <span class="number">0</span> <span class="operator">?</span> requestedSize<span class="operator">.</span>height() : height); pixmap<span class="operator">.</span>fill(<span class="type">QColor</span>(id)<span class="operator">.</span>rgba()); <span class="comment">// write the color name</span> <span class="type">QPainter</span> painter(<span class="operator">&</span>pixmap); <span class="type">QFont</span> f <span class="operator">=</span> painter<span class="operator">.</span>font(); f<span class="operator">.</span>setPixelSize(<span class="number">20</span>); painter<span class="operator">.</span>setFont(f); painter<span class="operator">.</span>setPen(<span class="type">Qt</span><span class="operator">::</span>black); <span class="keyword">if</span> (requestedSize<span class="operator">.</span>isValid()) painter<span class="operator">.</span>scale(requestedSize<span class="operator">.</span>width() <span class="operator">/</span> width<span class="operator">,</span> requestedSize<span class="operator">.</span>height() <span class="operator">/</span> height); painter<span class="operator">.</span>drawText(<span class="type">QRectF</span>(<span class="number">0</span><span class="operator">,</span> <span class="number">0</span><span class="operator">,</span> width<span class="operator">,</span> height)<span class="operator">,</span> <span class="type">Qt</span><span class="operator">::</span>AlignCenter<span class="operator">,</span> id); <span class="keyword">return</span> pixmap; } }; <span class="keyword">class</span> ImageProviderExtensionPlugin : <span class="keyword">public</span> <span class="type">QQmlExtensionPlugin</span> { Q_OBJECT Q_PLUGIN_METADATA(IID QQmlExtensionInterface_iid) <span class="keyword">public</span>: <span class="type">void</span> registerTypes(<span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>uri) override { Q_UNUSED(uri); } <span class="type">void</span> initializeEngine(<span class="type">QQmlEngine</span> <span class="operator">*</span>engine<span class="operator">,</span> <span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>uri) override { Q_UNUSED(uri); engine<span class="operator">-</span><span class="operator">></span>addImageProvider(<span class="string">"colors"</span><span class="operator">,</span> <span class="keyword">new</span> ColorImageProvider); } }; <span class="preprocessor">#include "imageprovider.moc"</span> </pre> </div> <!-- @@@imageprovider/imageprovider.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>