main.cpp Example File

  /****************************************************************************
  **
  ** 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.
  **
  ** $QT_END_LICENSE$
  **
  ****************************************************************************/

  #include <QtWidgets/QApplication>
  #include <QtWidgets/QMainWindow>
  #include <QtCharts/QChartView>
  #include <QtCharts/QLineSeries>
  #include <QtCore/QDateTime>
  #include <QtCharts/QDateTimeAxis>
  #include <QtCore/QFile>
  #include <QtCore/QTextStream>
  #include <QtCore/QDebug>
  #include <QtCharts/QValueAxis>

  QT_CHARTS_USE_NAMESPACE

  int main(int argc, char *argv[])
  {
      QApplication a(argc, argv);
      qsrand(QTime(0, 0, 0).secsTo(QTime::currentTime()));

      QLineSeries *series = new QLineSeries();

      // data from http://www.swpc.noaa.gov/ftpdir/weekly/RecentIndices.txt
      // http://www.swpc.noaa.gov/ftpdir/weekly/README
      // http://www.weather.gov/disclaimer
      QFile sunSpots(":sun");
      if (!sunSpots.open(QIODevice::ReadOnly | QIODevice::Text)) {
          return 1;
      }

      QTextStream stream(&sunSpots);
      while (!stream.atEnd()) {
          QString line = stream.readLine();
          if (line.startsWith("#") || line.startsWith(":"))
              continue;
          QStringList values = line.split(" ", QString::SkipEmptyParts);
          QDateTime momentInTime;
          momentInTime.setDate(QDate(values[0].toInt(), values[1].toInt() , 15));
          series->append(momentInTime.toMSecsSinceEpoch(), values[2].toDouble());
      }
      sunSpots.close();

      QChart *chart = new QChart();
      chart->addSeries(series);
      chart->legend()->hide();
      chart->setTitle("Sunspots count (by Space Weather Prediction Center)");

      QDateTimeAxis *axisX = new QDateTimeAxis;
      axisX->setTickCount(10);
      axisX->setFormat("MMM yyyy");
      axisX->setTitleText("Date");
      chart->addAxis(axisX, Qt::AlignBottom);
      series->attachAxis(axisX);

      QValueAxis *axisY = new QValueAxis;
      axisY->setLabelFormat("%i");
      axisY->setTitleText("Sunspots count");
      chart->addAxis(axisY, Qt::AlignLeft);
      series->attachAxis(axisY);

      QChartView *chartView = new QChartView(chart);
      chartView->setRenderHint(QPainter::Antialiasing);

      QMainWindow window;
      window.setCentralWidget(chartView);
      window.resize(820, 600);
      window.show();

      return a.exec();
  }