chartview.cpp Example File

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  #include "chartview.h"
  #include <QtCore/QtMath>
  #include <QtCore/QDebug>

  QT_CHARTS_USE_NAMESPACE

  ChartView::ChartView(QWidget *parent)
      : QChartView(new QChart(), parent),
        m_scatter(0),
        m_scatter2(0)
  {
      setRenderHint(QPainter::Antialiasing);

      chart()->setTitle("Click to interact with scatter points");

      m_scatter = new QScatterSeries();
      m_scatter->setName("scatter1");
      for (qreal x(0.5); x <= 4.0; x += 0.5) {
          for (qreal y(0.5); y <= 4.0; y += 0.5) {
              *m_scatter << QPointF(x, y);
          }
      }
      m_scatter2 = new QScatterSeries();
      m_scatter2->setName("scatter2");

      chart()->addSeries(m_scatter2);
      chart()->addSeries(m_scatter);
      chart()->createDefaultAxes();
      chart()->axisX()->setRange(0, 4.5);
      chart()->axisY()->setRange(0, 4.5);

      connect(m_scatter, SIGNAL(clicked(QPointF)), this, SLOT(handleClickedPoint(QPointF)));
  }

  ChartView::~ChartView()
  {
  }

  void ChartView::handleClickedPoint(const QPointF &point)
  {
      QPointF clickedPoint = point;
      // Find the closest point from series 1
      QPointF closest(INT_MAX, INT_MAX);
      qreal distance(INT_MAX);
      foreach (QPointF currentPoint, m_scatter->points()) {
          qreal currentDistance = qSqrt((currentPoint.x() - clickedPoint.x())
                                        * (currentPoint.x() - clickedPoint.x())
                                        + (currentPoint.y() - clickedPoint.y())
                                        * (currentPoint.y() - clickedPoint.y()));
          if (currentDistance < distance) {
              distance = currentDistance;
              closest = currentPoint;
          }
      }

      // Remove the closes point from series 1 and append it to series 2
      m_scatter->remove(closest);
      m_scatter2->append(closest);
  }