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<h1 class="title">xyseriesiodevice.cpp Example File</h1>
<span class="subtitle">audio/xyseriesiodevice.cpp</span>
<!-- $$$audio/xyseriesiodevice.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 "xyseriesiodevice.h"</span>
<span class="preprocessor">#include <QtCharts/QXYSeries></span>
XYSeriesIODevice<span class="operator">::</span>XYSeriesIODevice(<span class="type"><a href="qxyseries.html">QXYSeries</a></span> <span class="operator">*</span>series<span class="operator">,</span> <span class="type">QObject</span> <span class="operator">*</span>parent) :
<span class="type">QIODevice</span>(parent)<span class="operator">,</span>
m_series(series)
{
}
<span class="type">qint64</span> XYSeriesIODevice<span class="operator">::</span>readData(<span class="type">char</span> <span class="operator">*</span>data<span class="operator">,</span> <span class="type">qint64</span> maxSize)
{
Q_UNUSED(data)
Q_UNUSED(maxSize)
<span class="keyword">return</span> <span class="operator">-</span><span class="number">1</span>;
}
<span class="type">qint64</span> XYSeriesIODevice<span class="operator">::</span>writeData(<span class="keyword">const</span> <span class="type">char</span> <span class="operator">*</span>data<span class="operator">,</span> <span class="type">qint64</span> maxSize)
{
<span class="keyword">static</span> <span class="keyword">const</span> <span class="type">int</span> resolution <span class="operator">=</span> <span class="number">4</span>;
<span class="keyword">if</span> (m_buffer<span class="operator">.</span>isEmpty()) {
m_buffer<span class="operator">.</span>reserve(sampleCount);
<span class="keyword">for</span> (<span class="type">int</span> i <span class="operator">=</span> <span class="number">0</span>; i <span class="operator"><</span> sampleCount; <span class="operator">+</span><span class="operator">+</span>i)
m_buffer<span class="operator">.</span>append(<span class="type">QPointF</span>(i<span class="operator">,</span> <span class="number">0</span>));
}
<span class="type">int</span> start <span class="operator">=</span> <span class="number">0</span>;
<span class="keyword">const</span> <span class="type">int</span> availableSamples <span class="operator">=</span> <span class="type">int</span>(maxSize) <span class="operator">/</span> resolution;
<span class="keyword">if</span> (availableSamples <span class="operator"><</span> sampleCount) {
start <span class="operator">=</span> sampleCount <span class="operator">-</span> availableSamples;
<span class="keyword">for</span> (<span class="type">int</span> s <span class="operator">=</span> <span class="number">0</span>; s <span class="operator"><</span> start; <span class="operator">+</span><span class="operator">+</span>s)
m_buffer<span class="operator">[</span>s<span class="operator">]</span><span class="operator">.</span>setY(m_buffer<span class="operator">.</span>at(s <span class="operator">+</span> availableSamples)<span class="operator">.</span>y());
}
<span class="keyword">for</span> (<span class="type">int</span> s <span class="operator">=</span> start; s <span class="operator"><</span> sampleCount; <span class="operator">+</span><span class="operator">+</span>s<span class="operator">,</span> data <span class="operator">+</span><span class="operator">=</span> resolution)
m_buffer<span class="operator">[</span>s<span class="operator">]</span><span class="operator">.</span>setY(<span class="type">qreal</span>(<span class="type">uchar</span>(<span class="operator">*</span>data) <span class="operator">-</span><span class="number">128</span>) <span class="operator">/</span> <span class="type">qreal</span>(<span class="number">128</span>));
m_series<span class="operator">-</span><span class="operator">></span>replace(m_buffer);
<span class="keyword">return</span> (sampleCount <span class="operator">-</span> start) <span class="operator">*</span> resolution;
}
</pre>
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<!-- @@@audio/xyseriesiodevice.cpp -->
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