Source code
Revision control
Copy as Markdown
// Copyright (C) 2023 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
#include "datasource.h"
#include <QAreaSeries>
#include <QQuickItem>
#include <QQuickView>
#include <QRandomGenerator>
#include <QtMath>
#include <QXYSeries>
Q_DECLARE_METATYPE(QAbstractSeries *)
Q_DECLARE_METATYPE(QAbstractAxis *)
DataSource::DataSource(QQuickView *appViewer, QObject *parent)
: QObject(parent)
, m_appViewer(appViewer)
{
qRegisterMetaType<QAbstractSeries*>();
qRegisterMetaType<QAbstractAxis*>();
generateData(0, 5, 1024);
}
void DataSource::update(QAbstractSeries *series)
{
if (series) {
auto xySeries = static_cast<QXYSeries *>(series);
m_index++;
if (m_index > m_data.count() - 1)
m_index = 0;
QList<QPointF> points = m_data.at(m_index);
// Use replace instead of clear + append, it's optimized for performance
xySeries->replace(points);
}
}
void DataSource::generateData(int type, int rowCount, int colCount)
{
// Remove previous data
m_data.clear();
// Append the new data depending on the type
for (int i(0); i < rowCount; i++) {
QList<QPointF> points;
points.reserve(colCount);
for (int j(0); j < colCount; j++) {
qreal x(0);
qreal y(0);
switch (type) {
case 0:
// data with sin + random component
y = qSin(M_PI / 50 * j) + 0.5 + QRandomGenerator::global()->generateDouble();
x = j;
break;
case 1:
// linear data
x = j;
y = (qreal) i / 10;
break;
default:
// unknown, do nothing
break;
}
points.append(QPointF(x, y));
}
m_data.append(points);
}
}