chartview.cpp Example File

zoomlinechart/chartview.cpp
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 #include "chartview.h"
 #include <QtGui/QMouseEvent>

 ChartView::ChartView(QChart *chart, QWidget *parent) :
     QChartView(chart, parent),
     m_isTouching(false)
 {
     setRubberBand(QChartView::RectangleRubberBand);
 }

 bool ChartView::viewportEvent(QEvent *event)
 {
     if (event->type() == QEvent::TouchBegin) {
         // By default touch events are converted to mouse events. So
         // after this event we will get a mouse event also but we want
         // to handle touch events as gestures only. So we need this safeguard
         // to block mouse events that are actually generated from touch.
         m_isTouching = true;

         // Turn off animations when handling gestures they
         // will only slow us down.
         chart()->setAnimationOptions(QChart::NoAnimation);
     }
     return QChartView::viewportEvent(event);
 }

 void ChartView::mousePressEvent(QMouseEvent *event)
 {
     if (m_isTouching)
         return;
     QChartView::mousePressEvent(event);
 }

 void ChartView::mouseMoveEvent(QMouseEvent *event)
 {
     if (m_isTouching)
         return;
     QChartView::mouseMoveEvent(event);
 }

 void ChartView::mouseReleaseEvent(QMouseEvent *event)
 {
     if (m_isTouching)
         m_isTouching = false;

     // Because we disabled animations when touch event was detected
     // we must put them back on.
     chart()->setAnimationOptions(QChart::SeriesAnimations);

     QChartView::mouseReleaseEvent(event);
 }

 void ChartView::keyPressEvent(QKeyEvent *event)
 {
     switch (event->key()) {
     case Qt::Key_Plus:
         chart()->zoomIn();
         break;
     case Qt::Key_Minus:
         chart()->zoomOut();
         break;
     case Qt::Key_Left:
         chart()->scroll(-10, 0);
         break;
     case Qt::Key_Right:
         chart()->scroll(10, 0);
         break;
     case Qt::Key_Up:
         chart()->scroll(0, 10);
         break;
     case Qt::Key_Down:
         chart()->scroll(0, -10);
         break;
     default:
         QGraphicsView::keyPressEvent(event);
         break;
     }
 }