public :
MyGraphics
(QWidget *parent
= NULL);
public slots:
void zoomIn() { scale(1.2, 1.2); }
void zoomOut() { scale(1 / 1.2, 1 / 1.2); }
protected :
bool rubberBandActive;
int _numScheduledScalings;
//if I uncomment these three event handlers, the wheelevent doesnt zoom properly!
// virtual void mousePressEvent(QMouseEvent *event);
// virtual void mouseMoveEvent(QMouseEvent *event);
// virtual void mouseReleaseEvent(QMouseEvent *event);
};
this->installEventFilter(this);
this->setScene(graphScene);
// QDebug << "Left " << sceneRect().
setSceneRect(0, 0, 1000, 1000);
rubberBandOrigin
= QPoint(0,
0);
}
double scaleFactor = 1.2;
if(event->delta() > 0){
//Zoom in
this->zoomIn();
//this->scale(scaleFactor,scaleFactor);
} else {
this->zoomOut();
//Zoom Out
//this->scale(1.0/scaleFactor, 1.0/scaleFactor);
}
//QGraphicsView::wheelEvent(event);
}
//Get the rectangle of the visible area in scene coords
QRectF visibleArea
= this
->mapToScene
(rect
()).
boundingRect();
this->fitInView(0,0,visibleArea.width(), visibleArea.height(),Qt::KeepAspectRatio);
//Call the subclass resize so the scrollbars are updated correctly
}
/*
void MyGraphics::mousePressEvent(QMouseEvent *event)
{
if (event->button() == Qt::MiddleButton) {
rubberBandOrigin = event->pos();
rubberBand = new QRubberBand(QRubberBand::Rectangle, this);
rubberBand->setGeometry(event->x(),event->y(),0, 0);
rubberBand->show();
rubberBandActive = true;
}
if(event->button() == Qt::LeftButton){
LastPanPoint = event->pos();
}
}
void MyGraphics::mouseMoveEvent(QMouseEvent *event)
{
if (event->buttons() == Qt::MiddleButton && rubberBandActive == true){
rubberBand->resize( event->x()-rubberBandOrigin.x(), event->y()-rubberBandOrigin.y() );
}
else{
if(!LastPanPoint.isNull()) {
//Get how much we panned
QGraphicsView * view = static_cast<QGraphicsView *>(this);
QPointF delta = view->mapToScene(LastPanPoint) - view->mapToScene(event->pos());
LastPanPoint = event->pos();
}
}
}
void MyGraphics::mouseReleaseEvent(QMouseEvent *event)
{
if (event->button() == Qt::MiddleButton){
QGraphicsView * view = static_cast<QGraphicsView *>(this);
QPoint rubberBandEnd = event->pos();
QRectF zoomRectInScene = QRectF(view->mapToScene(rubberBandOrigin), view->mapToScene(rubberBandEnd));
QPointF center = zoomRectInScene.center();
view->fitInView(zoomRectInScene, Qt::KeepAspectRatio);
rubberBandActive = false;
delete rubberBand;
}
else{
LastPanPoint = QPoint();
}
}
*/
class MyGraphics : public QGraphicsView{
public :
MyGraphics(QWidget *parent = NULL);
public slots:
void zoomIn() { scale(1.2, 1.2); }
void zoomOut() { scale(1 / 1.2, 1 / 1.2); }
protected :
QRubberBand *rubberBand;
QPoint origin;
QPointF InitialCenterPoint;
QPointF CurrentCenterPoint;
QPoint rubberBandOrigin;
bool rubberBandActive;
QPoint LastPanPoint;
int _numScheduledScalings;
//if I uncomment these three event handlers, the wheelevent doesnt zoom properly!
// virtual void mousePressEvent(QMouseEvent *event);
// virtual void mouseMoveEvent(QMouseEvent *event);
// virtual void mouseReleaseEvent(QMouseEvent *event);
virtual void wheelEvent(QWheelEvent *);
virtual void resizeEvent(QResizeEvent *event);
};
MyGraphics::MyGraphics(QWidget *parent) : QGraphicsView(parent){
setRenderHints(QPainter::Antialiasing | QPainter::SmoothPixmapTransform);
this->installEventFilter(this);
this->setTransformationAnchor(QGraphicsView::AnchorUnderMouse);
this->setResizeAnchor( QGraphicsView::AnchorUnderMouse );
QGraphicsScene *graphScene = new QGraphicsScene(this);
this->setScene(graphScene);
// QDebug << "Left " << sceneRect().
QGraphicsItem* pEllipse = graphScene->addEllipse(0,100,50,50);
QGraphicsItem* pRect = graphScene->addRect(200,100,50,50);
pEllipse->setFlag(QGraphicsItem::ItemIsSelectable, true);
pRect->setFlag(QGraphicsItem::ItemIsSelectable, true);
setSceneRect(0, 0, 1000, 1000);
rubberBandOrigin = QPoint(0,0);
}
void MyGraphics::wheelEvent(QWheelEvent *event){
double scaleFactor = 1.2;
if(event->delta() > 0){
//Zoom in
this->zoomIn();
//this->scale(scaleFactor,scaleFactor);
} else {
this->zoomOut();
//Zoom Out
//this->scale(1.0/scaleFactor, 1.0/scaleFactor);
}
//QGraphicsView::wheelEvent(event);
}
void MyGraphics::resizeEvent(QResizeEvent* event) {
//Get the rectangle of the visible area in scene coords
QRectF visibleArea = this->mapToScene(rect()).boundingRect();
this->fitInView(0,0,visibleArea.width(), visibleArea.height(),Qt::KeepAspectRatio);
//Call the subclass resize so the scrollbars are updated correctly
QGraphicsView::resizeEvent(event);
}
/*
void MyGraphics::mousePressEvent(QMouseEvent *event)
{
if (event->button() == Qt::MiddleButton) {
rubberBandOrigin = event->pos();
rubberBand = new QRubberBand(QRubberBand::Rectangle, this);
rubberBand->setGeometry(event->x(),event->y(),0, 0);
rubberBand->show();
rubberBandActive = true;
}
if(event->button() == Qt::LeftButton){
LastPanPoint = event->pos();
}
}
void MyGraphics::mouseMoveEvent(QMouseEvent *event)
{
if (event->buttons() == Qt::MiddleButton && rubberBandActive == true){
rubberBand->resize( event->x()-rubberBandOrigin.x(), event->y()-rubberBandOrigin.y() );
}
else{
if(!LastPanPoint.isNull()) {
//Get how much we panned
QGraphicsView * view = static_cast<QGraphicsView *>(this);
QPointF delta = view->mapToScene(LastPanPoint) - view->mapToScene(event->pos());
LastPanPoint = event->pos();
}
}
}
void MyGraphics::mouseReleaseEvent(QMouseEvent *event)
{
if (event->button() == Qt::MiddleButton){
QGraphicsView * view = static_cast<QGraphicsView *>(this);
QPoint rubberBandEnd = event->pos();
QRectF zoomRectInScene = QRectF(view->mapToScene(rubberBandOrigin), view->mapToScene(rubberBandEnd));
QPointF center = zoomRectInScene.center();
view->fitInView(zoomRectInScene, Qt::KeepAspectRatio);
rubberBandActive = false;
delete rubberBand;
}
else{
LastPanPoint = QPoint();
}
}
*/
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