<?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>datasource.cpp Example File | Qt Charts 5.9</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 5.9</td><td ><a href="qtcharts-index.html">Qt Charts</a></td><td ><a href="qtcharts-qmloscilloscope-example.html">Qml Oscilloscope</a></td><td >datasource.cpp Example File</td></tr></table><table class="buildversion"><tr> <td id="buildversion" width="100%" align="right">Qt 5.9.4 Reference Documentation</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">datasource.cpp Example File</h1> <span class="subtitle">qmloscilloscope/datasource.cpp</span> <!-- $$$qmloscilloscope/datasource.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 Qt Charts module of the Qt Toolkit. ** ** $QT_BEGIN_LICENSE:GPL$ ** 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. ** ** GNU General Public License Usage ** Alternatively, this file may be used under the terms of the GNU ** General Public License version 3 or (at your option) any later version ** approved by the KDE Free Qt Foundation. The licenses are as published by ** the Free Software Foundation and appearing in the file LICENSE.GPL3 ** included in the packaging of this file. Please review the following ** information to ensure the GNU General Public License requirements will ** be met: https://www.gnu.org/licenses/gpl-3.0.html. ** ** $QT_END_LICENSE$ ** ****************************************************************************/</span> <span class="preprocessor">#include "datasource.h"</span> <span class="preprocessor">#include <QtCharts/QXYSeries></span> <span class="preprocessor">#include <QtCharts/QAreaSeries></span> <span class="preprocessor">#include <QtQuick/QQuickView></span> <span class="preprocessor">#include <QtQuick/QQuickItem></span> <span class="preprocessor">#include <QtCore/QDebug></span> <span class="preprocessor">#include <QtCore/QtMath></span> QT_CHARTS_USE_NAMESPACE Q_DECLARE_METATYPE(<span class="type"><a href="qabstractseries.html">QAbstractSeries</a></span> <span class="operator">*</span>) Q_DECLARE_METATYPE(<span class="type"><a href="qabstractaxis.html">QAbstractAxis</a></span> <span class="operator">*</span>) DataSource<span class="operator">::</span>DataSource(<span class="type">QQuickView</span> <span class="operator">*</span>appViewer<span class="operator">,</span> <span class="type">QObject</span> <span class="operator">*</span>parent) : <span class="type">QObject</span>(parent)<span class="operator">,</span> m_appViewer(appViewer)<span class="operator">,</span> m_index(<span class="operator">-</span><span class="number">1</span>) { qRegisterMetaType<span class="operator"><</span><span class="type"><a href="qabstractseries.html">QAbstractSeries</a></span><span class="operator">*</span><span class="operator">></span>(); qRegisterMetaType<span class="operator"><</span><span class="type"><a href="qabstractaxis.html">QAbstractAxis</a></span><span class="operator">*</span><span class="operator">></span>(); generateData(<span class="number">0</span><span class="operator">,</span> <span class="number">5</span><span class="operator">,</span> <span class="number">1024</span>); } <span class="type">void</span> DataSource<span class="operator">::</span>update(<span class="type"><a href="qabstractseries.html">QAbstractSeries</a></span> <span class="operator">*</span>series) { <span class="keyword">if</span> (series) { <span class="type"><a href="qxyseries.html">QXYSeries</a></span> <span class="operator">*</span>xySeries <span class="operator">=</span> <span class="keyword">static_cast</span><span class="operator"><</span><span class="type"><a href="qxyseries.html">QXYSeries</a></span> <span class="operator">*</span><span class="operator">></span>(series); m_index<span class="operator">+</span><span class="operator">+</span>; <span class="keyword">if</span> (m_index <span class="operator">></span> m_data<span class="operator">.</span>count() <span class="operator">-</span> <span class="number">1</span>) m_index <span class="operator">=</span> <span class="number">0</span>; <span class="type">QVector</span><span class="operator"><</span><span class="type">QPointF</span><span class="operator">></span> points <span class="operator">=</span> m_data<span class="operator">.</span>at(m_index); <span class="comment">// Use replace instead of clear + append, it's optimized for performance</span> xySeries<span class="operator">-</span><span class="operator">></span>replace(points); } } <span class="type">void</span> DataSource<span class="operator">::</span>generateData(<span class="type">int</span> type<span class="operator">,</span> <span class="type">int</span> rowCount<span class="operator">,</span> <span class="type">int</span> colCount) { <span class="comment">// Remove previous data</span> m_data<span class="operator">.</span>clear(); <span class="comment">// Append the new data depending on the type</span> <span class="keyword">for</span> (<span class="type">int</span> i(<span class="number">0</span>); i <span class="operator"><</span> rowCount; i<span class="operator">+</span><span class="operator">+</span>) { <span class="type">QVector</span><span class="operator"><</span><span class="type">QPointF</span><span class="operator">></span> points; points<span class="operator">.</span>reserve(colCount); <span class="keyword">for</span> (<span class="type">int</span> j(<span class="number">0</span>); j <span class="operator"><</span> colCount; j<span class="operator">+</span><span class="operator">+</span>) { <span class="type">qreal</span> x(<span class="number">0</span>); <span class="type">qreal</span> y(<span class="number">0</span>); <span class="keyword">switch</span> (type) { <span class="keyword">case</span> <span class="number">0</span>: <span class="comment">// data with sin + random component</span> y <span class="operator">=</span> qSin(<span class="number">3.14159265358979</span> <span class="operator">/</span> <span class="number">50</span> <span class="operator">*</span> j) <span class="operator">+</span> <span class="number">0.5</span> <span class="operator">+</span> (<span class="type">qreal</span>) rand() <span class="operator">/</span> (<span class="type">qreal</span>) RAND_MAX; x <span class="operator">=</span> j; <span class="keyword">break</span>; <span class="keyword">case</span> <span class="number">1</span>: <span class="comment">// linear data</span> x <span class="operator">=</span> j; y <span class="operator">=</span> (<span class="type">qreal</span>) i <span class="operator">/</span> <span class="number">10</span>; <span class="keyword">break</span>; <span class="keyword">default</span>: <span class="comment">// unknown, do nothing</span> <span class="keyword">break</span>; } points<span class="operator">.</span>append(<span class="type">QPointF</span>(x<span class="operator">,</span> y)); } m_data<span class="operator">.</span>append(points); } } </pre> </div> <!-- @@@qmloscilloscope/datasource.cpp --> </div> </div> </div> </div> </div> <div class="footer"> <p> <acronym title="Copyright">©</acronym> 2017 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>