QtCharts setRange issue

[Cobra91151]

Hello!

I want to display some data using QtCharts. I have tried the DynamicSpline example, it works well but when I set my data then nothing is displayed. I think the problem is with the setRange method.

Code:

chart.h:

#ifndef CHART_H
#define CHART_H

#include <QChart>
#include <QTimer>
#include <QAbstractAxis>
#include <QSplineSeries>
#include <QValueAxis>
#include <QDebug>

QT_CHARTS_BEGIN_NAMESPACE
class QSplineSeries;
class QValueAxis;
QT_CHARTS_END_NAMESPACE

QT_CHARTS_USE_NAMESPACE

class Chart: public QChart
{
    Q_OBJECT
public:
    Chart(QGraphicsItem *parent = 0, Qt::WindowFlags wFlags = 0);
    virtual ~Chart();

public slots:
    void handleTimeout();

private:
    QTimer m_timer;
    QSplineSeries *m_series;
    QStringList m_titles;
    QValueAxis *m_axisX;
    QValueAxis *m_axisY;
    qreal m_step;
    qreal m_x;
    qreal m_y;
    QList<double> testList;
};

#endif /* CHART_H */

chart.cpp:

#include "chart.h"

Chart::Chart(QGraphicsItem *parent, Qt::WindowFlags wFlags):
    QChart(QChart::ChartTypeCartesian, parent, wFlags),
    m_series(0),
    m_step(0),
    m_x(1),
    m_y(1)
{
    m_axisX = new QValueAxis(this);
    m_axisX->setLabelsVisible(false);
    m_axisY = new QValueAxis(this);
    m_axisY->setLabelsVisible(false);
    connect(&m_timer, &QTimer::timeout, this, &Chart::handleTimeout);
    m_timer.setInterval(1000);
    m_series = new QSplineSeries(this);
    QPen green(Qt::green);
    green.setWidth(3);
    m_series->setPen(green);
    m_series->append(m_x, m_y);
    legend()->hide();
    addSeries(m_series);
    setAxisX(m_axisX, m_series);
    setAxisY(m_axisY, m_series);
    m_axisX->setTickCount(5);
    testList << 93.8436 << 777.797 << 2507.78 << 5999.44 << 6806.54 << 7481.16
                 << 8008.5 << 8093.8 << 8161.83 << 8216.99
                 << 8280.46 << 8328.4 << 8394.55 << 8469.84
                 << 8500.65 << 8558.16 << 8660.9 << 8638.87
                 << 8726.47 << 8715.25 << 8804.48 << 8793.86
                 << 8839.42 << 8875.75 << 8938.24 << 8977.09
                 << 9020.27 << 9046.7 << 9092.04 << 9121.58
                 << 9155.36 << 9199.46;

    axisX()->setRange(0, 100);
    axisY()->setRange(-1, 100);
    m_timer.start();
}

void Chart::handleTimeout()
{
    qreal x = plotArea().width() / m_axisX->tickCount();
    qreal y = (m_axisX->max() - m_axisX->min()) / m_axisX->tickCount();
    m_x += y;

    if (!testList.isEmpty()) {
        m_y = testList.first();
        testList.takeFirst();
    }

    qDebug() << "m_x: " << m_x << " " << "m_y: " << m_y;
    m_series->append(m_x, m_y);
    scroll(x, 0);
}

Chart::~Chart()
{

}

main.cpp:

#include "chart.h"
#include <QChartView>
#include <QApplication>
#include <QWidget>
#include <QHBoxLayout>

QT_CHARTS_USE_NAMESPACE

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWidget window;
    Chart *chart = new Chart;
    //chart->setTitle("Dynamic spline chart");
    chart->setAnimationOptions(QChart::AllAnimations);
    QChartView chartView(chart);
    chartView.setRenderHint(QPainter::Antialiasing);
    chartView.resize(window.size());
    QHBoxLayout *layout = new QHBoxLayout();
    layout->addWidget(&chartView);
    window.setLayout(layout);
    window.setMinimumSize(810, 400);
    window.show();
    return a.exec();
}

Any ideas how to fix it? Thanks.

[Cobra91151]

Hello!

I have fixed the issue by using QtNetworkMonitor example from GitHub. The issue is resolved.

[Cobra91151]

I have fixed the issue. Now it works well, but I need to set the axis rect background color.

Screenshot:

Any ideas how to set the axis background color? Thanks.

[Cobra91151]

Hello!

I tried to use the QAreaSeries to set the axis rect background. But it displays: "Can not find series on the chart.",
"Can not find series on the chart." issues and draw incorrectly.

Screenshot:

Code:
chart.h

#ifndef CHART_H
#define CHART_H

#include <QChart>
#include <QTimer>
#include <QAbstractAxis>
#include <QLineSeries>
#include <QValueAxis>
#include <QAreaSeries>
#include <QDebug>

QT_CHARTS_BEGIN_NAMESPACE
class QLineSeries;
class QValueAxis;
QT_CHARTS_END_NAMESPACE

QT_CHARTS_USE_NAMESPACE

class Chart: public QChart
{
    Q_OBJECT
public:
    Chart(QGraphicsItem *parent = 0, Qt::WindowFlags wFlags = 0);
    void setLabelsOn(bool isOn);
    void setPenStyle(QColor color, int width);
    void setLegendOn(bool isOn);
    void setAxisGridLineOn(bool isOn);
    virtual ~Chart();

public slots:
    void handleTimeout();

private:
    QTimer m_timer;
    QLineSeries *m_series;
    QLineSeries *series1;
    QValueAxis *m_axisX;
    QValueAxis *m_axisY;
    qreal m_x;
    qreal m_y;
    QList<double> testList;
    QAreaSeries *areaSeries;
};

#endif /* CHART_H */

chart.cpp

#include "chart.h"

Chart::Chart(QGraphicsItem *parent, Qt::WindowFlags wFlags):
    QChart(QChart::ChartTypeCartesian, parent, wFlags),
    m_series(nullptr),
    m_x(5),
    m_y(0)
{
    m_axisX = new QValueAxis(this);
    m_axisY = new QValueAxis(this);
    m_series = new QLineSeries(this);
    m_series->append(m_x, m_y);
    series1 = new QLineSeries(this);
    series1->append(1, 1);
    testList << 93.8436 << 777.797 << 2507.78 << 5999.44 << 6806.54 << 7481.16
             << 8008.5 << 1500.5 << 8328.4 << 1998.4 << 9092.04 << 1885.60 << 8093.8 << 8161.83 << 8216.99
             << 8280.46 << 8394.55 << 8469.84
             << 8500.65 << 2500.88 << 8558.16 << 8660.9 << 8638.87
             << 8726.47 << 8715.25 << 8804.48 << 8793.86
             << 8839.42 << 8875.75 << 8938.24 << 8977.09
             << 9020.27 << 9046.7 << 9092.04 << 9121.58
             << 9155.36 << 9199.46 << 10 << 8 << 3 << 1 << 0;
    areaSeries = new QAreaSeries(m_series, series1);
    areaSeries->setBrush(QBrush(QColor(Qt::red)));
    addSeries(areaSeries);
    setAxisX(m_axisX, m_series);
    setAxisY(m_axisY, m_series);
    m_axisX->setTickCount(5);
    m_axisX->setRange(0, 5);
    m_axisY->setRange(0, 9199.4);
    connect(&m_timer, &QTimer::timeout, this, &Chart::handleTimeout);
    m_timer.setInterval(1000);
    m_timer.start();
}

void Chart::setAxisGridLineOn(bool isOn)
{
    m_axisX->setGridLineVisible(isOn);
    m_axisY->setGridLineVisible(isOn);
}

void Chart::setLegendOn(bool isOn)
{
    if (isOn) {
        legend()->show();
    } else {
        legend()->hide();
    }
}

void Chart::setPenStyle(QColor color, int width)
{
    QPen pen(color);
    pen.setWidth(width);
    m_series->setPen(pen);
}

void Chart::setLabelsOn(bool isOn)
{
    m_axisX->setLabelsVisible(isOn);
    m_axisY->setLabelsVisible(isOn);
}

void Chart::handleTimeout()
{
    qreal x = plotArea().width() / m_axisX->tickCount();
    qreal y = (m_axisX->max() - m_axisX->min()) / m_axisX->tickCount();
    m_x += y;

    if (!testList.isEmpty()) {
        m_y = testList.first();
        testList.takeFirst();
    } else {
        m_timer.stop();
    }

    qDebug() << "m_x: " << m_x << " " << "m_y: " << m_y;
    m_series->append(m_x, m_y);
    series1->append(m_y, 0);
    scroll(x, 0);
}

Chart::~Chart()
{

}

main.cpp

#include "chart.h"
#include <QChartView>
#include <QApplication>
#include <QWidget>
#include <QHBoxLayout>
#include <QGraphicsLayout>

int main(int argc, char *argv[])
{
    QApplication a(argc, argv);
    QWidget window;
    window.setWindowTitle("Test Chart Widget");
    Chart *chart = new Chart;
    chart->setLabelsOn(true);
    chart->setPenStyle(Qt::blue, 1);
    chart->setLegendOn(false);
    chart->setBackgroundRoundness(1);
    chart->setAxisGridLineOn(true);
    //chart->setContentsMargins(-60, -25, -25, -40);
    chart->layout()->setContentsMargins(0, 0, 0, 0);
    chart->setAnimationOptions(QChart::AllAnimations);
    QChartView chartView(chart);
    chartView.setStyleSheet("border: 1px solid blue;");
    chartView.setRenderHint(QPainter::Antialiasing);
    QHBoxLayout *layout = new QHBoxLayout();
    layout->setContentsMargins(QMargins());
    layout->addWidget(&chartView);
    window.setLayout(layout);
    window.setMinimumSize(810, 400);
    window.show();
    return a.exec();
}

How to draw it properly? Thanks.

[Cobra91151]

Hello!

I have fixed the issue by using QtNetworkMonitor example from GitHub. The issue is resolved.