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; } }