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<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>
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<!-- @@@qmloscilloscope/datasource.cpp -->
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distrib
>
Mageia
>
6
>
x86_64
>
media
>
core-updates
>
by-pkgid
>
19952c5e751bf7e3108c3c59625b0f35
>
files
>
449
