qgraphicscene mousemove mouse position help

[ear9mrn]

HI,

I am trying to capture the mouse position relative to a graphicsscene. See code below, the X and Y values in the bottom right are for the view, I would like the values for the scene, I so when I hover ove the top right cross is says 250,250 etc.:

I am stumped any help would be appreciated.

Thanks,

Pete.



#include <QApplication>
#include <QMainWindow>
#include <QStatusBar>
#include <QGraphicsView>
#include <QGraphicsScene>
#include <QGraphicsSceneMouseEvent>
#include <QGraphicsTextItem>
#include <QMouseEvent>
#include <QScrollBar>
#include <QLabel>
#include <math.h>
#include <QtGui>


class MapView : public QGraphicsView
{

public:
MapView(QWidget *parent = 0);
QPoint sceneCoordinates;
QLabel *coordinateDisplayLabel;

protected:
void scaleView(qreal scaleFactor);
void wheelEvent(QWheelEvent *event);
void mousePressEvent(QMouseEvent *event);
void mouseMoveEvent(QMouseEvent *event);
void mouseReleaseEvent(QMouseEvent *event);
void mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent);
void mousePressEvent(QGraphicsSceneMouseEvent *mouseEvent);


private:
QString cursorXString;
QString cursorYString;
void storeMouseEvent(QMouseEvent *event);
bool scrolling;
QMouseEvent lastMouseEvent;

};

MapView::MapView(QWidget *parent)
: QGraphicsView(parent), lastMouseEvent(QEvent::None,QPoint(),
Qt::NoButton,Qt::NoButton,Qt::NoModifier)

{
QGraphicsScene scene;
setAttribute (Qt::WA_SetCursor);
setCursor(Qt::CrossCursor);
scale(1,-1);
coordinateDisplayLabel = new QLabel(0);
setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOf f);
setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff) ;
setTransformationAnchor(QGraphicsView::AnchorUnder Mouse);
scrolling = false;
}

void MapView::wheelEvent(QWheelEvent *event)
{
scaleView(pow((double)2, event->delta() / 240.0));
}

void MapView::scaleView(qreal scaleFactor)
{
qreal factor = matrix().scale(scaleFactor, scaleFactor).mapRect(QRectF(0, 0, 1, 1)).width();
if (factor < 0.07 || factor > 100)
return;
scale(scaleFactor, scaleFactor);
}

void MapView::storeMouseEvent(QMouseEvent *event)
{
lastMouseEvent = QMouseEvent(event->type(), event->pos(), event->globalPos(),
event->button(),event->buttons(),event->modifiers());

}

void MapView::mousePressEvent(QMouseEvent *event)
{
if(event->button() == Qt::MidButton)
{
setCursor(Qt::ClosedHandCursor);
scrolling = true;
storeMouseEvent(event);
event->accept();
return;
}
}
void MapView::mouseMoveEvent(QGraphicsSceneMouseEvent *mouseEvent)
{
//QGraphicsScene::mousePressEvent(mouseEvent);
qDebug() << mouseEvent->scenePos();

}
void MapView::mouseMoveEvent(QMouseEvent *event)
{

if(scrolling)
{
QPoint delta = event->globalPos() - lastMouseEvent.globalPos();
QScrollBar *hBar = horizontalScrollBar();
QScrollBar *vBar = verticalScrollBar();
hBar->setValue(hBar->value() - delta.x());
vBar->setValue(vBar->value() - delta.y());
storeMouseEvent(event);
event->accept();
return;
}

sceneCoordinates = mapFromScene(event->pos());
cursorXString.setNum(sceneCoordinates.x());
cursorYString.setNum(sceneCoordinates.y());
coordinateDisplayLabel->setText("x = " + cursorXString + " " + "y = " + cursorYString);
}

void MapView::mouseReleaseEvent(QMouseEvent *event)
{
if((event->button() == Qt::MidButton) && (scrolling == true))
{
setCursor(Qt::CrossCursor);
scrolling = false;
storeMouseEvent(event);
event->accept();
return;
}
event->ignore();
}


int main( int argc, char **argv )
{
QApplication a( argc, argv );
QMainWindow *mw = new QMainWindow();
MapView *view = new MapView;
QStatusBar *statusbar = new QStatusBar;
QGraphicsScene *scene = new QGraphicsScene;

scene->setSceneRect(-30000, -30000, 60000, 60000);
scene->setBackgroundBrush(Qt::black);

scene->addLine ( -50, 0, 50, 0, (QPen(Qt::white, 0)));
scene->addLine ( 0, -50, 0, 50, (QPen(Qt::white, 0)));
QGraphicsTextItem item1("0,0");
item1.setDefaultTextColor(Qt::white);
item1.setPos(0,0);
item1.scale(1,-1);
scene->addItem(&item1);

scene->addLine ( 200, 250, 300, 250, (QPen(Qt::white, 0)));
scene->addLine ( 250, 300, 250, 200, (QPen(Qt::white, 0)));
QGraphicsTextItem item2("250,250");
item2.setDefaultTextColor(Qt::white);
item2.setPos(250,250);
item2.scale(1,-1);
scene->addItem(&item2);

view->setScene(scene);
mw->setCentralWidget(view);
statusbar->addPermanentWidget(view->coordinateDisplayLabel, 0);
mw->setStatusBar(statusbar);

mw->show();

return a.exec();
}