main.cpp Example File

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  ** Copyright (C) 2016 The Qt Company Ltd.
  ** Contact: https://www.qt.io/licensing/
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  ** This file is part of the Qt Charts module of the Qt Toolkit.
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  #include <QtWidgets/QApplication>
  #include <QtWidgets/QMainWindow>
  #include <QtCharts/QChartView>
  #include <QtCharts/QBarSet>
  #include <QtCharts/QLegend>
  #include "drilldownseries.h"
  #include "drilldownchart.h"

  QT_CHARTS_USE_NAMESPACE

  int main(int argc, char *argv[])
  {
      QApplication a(argc, argv);
      QMainWindow window;

      DrilldownChart *drilldownChart =  new DrilldownChart();
      drilldownChart->setAnimationOptions(QChart::SeriesAnimations);

      // Define categories
      QStringList months;
      months << "May" << "Jun" << "Jul" << "Aug" << "Sep";
      QStringList weeks;
      weeks << "week 1" << "week 2" << "week 3" << "week 4";
      QStringList plants;
      plants << "Habanero" << "Lemon Drop" << "Starfish" << "Aji Amarillo";

      // Create drilldown structure
      DrilldownBarSeries *seasonSeries = new DrilldownBarSeries(months, drilldownChart);
      seasonSeries->setName("Crop by month - Season");

      // Each month in season series has drilldown series for weekly data
      for (int month = 0; month < months.count(); month++) {

          // Create drilldown series for every week
          DrilldownBarSeries *weeklySeries = new DrilldownBarSeries(weeks, drilldownChart);
          seasonSeries->mapDrilldownSeries(month, weeklySeries);

          // Drilling down from weekly data brings us back to season data.
          for (int week = 0; week < weeks.count(); week++) {
              weeklySeries->mapDrilldownSeries(week, seasonSeries);
              weeklySeries->setName(QString("Crop by week - " + months.at(month)));
          }

          // Use clicked signal to implement drilldown
          QObject::connect(weeklySeries, SIGNAL(clicked(int,QBarSet*)), drilldownChart, SLOT(handleClicked(int,QBarSet*)));
      }

      // Enable drilldown from season series using clicked signal
      QObject::connect(seasonSeries, SIGNAL(clicked(int,QBarSet*)), drilldownChart, SLOT(handleClicked(int,QBarSet*)));

      // Fill monthly and weekly series with data
      foreach (QString plant, plants) {
          QBarSet *monthlyCrop = new QBarSet(plant);
          for (int month = 0; month < months.count(); month++) {
              QBarSet *weeklyCrop = new QBarSet(plant);
              for (int week = 0; week < weeks.count(); week++)
                  *weeklyCrop << (qrand() % 20);
              // Get the drilldown series from season series and add crop to it.
              seasonSeries->drilldownSeries(month)->append(weeklyCrop);
              *monthlyCrop << weeklyCrop->sum();
          }
          seasonSeries->append(monthlyCrop);
      }

      // Show season series in initial view
      drilldownChart->changeSeries(seasonSeries);
      drilldownChart->setTitle(seasonSeries->name());

      drilldownChart->axisX()->setGridLineVisible(false);
      drilldownChart->legend()->setVisible(true);
      drilldownChart->legend()->setAlignment(Qt::AlignBottom);

      QChartView *chartView = new QChartView(drilldownChart);
      window.setCentralWidget(chartView);
      window.resize(480, 300);
      window.show();

      return a.exec();
  }