Detecting and reacting to mouse dragging in QGraphicsView?

[swbluto]

Ok, I figured out how to detection using the MousePressEvent and MouseReleaseEvent and MouseMove event to do the "detect the mouse is dragging" part, now I need to retrieve the position of the mouse to do image-moving calculations. Does anyone have a snippet of code to do this?

I have this code currently, but it complains.

void mapScene::mouseMoveEvent( QGraphicsSceneMouseEvent * event)
{
    debug("I vus here 2!");
    prevMousePoint = event->lastPos();
    currMousePoint = event->pos();
    if(mouseDown)
    {
 
         // xOffset = event->pos().x() - event->lastPos().x();
          //yOffset = 1;
    }
}

void mapScene::mouseMoveEvent( QGraphicsSceneMouseEvent * event)
{
    debug("I vus here 2!");
    prevMousePoint = event->lastPos();
    currMousePoint = event->pos();
    if(mouseDown)
    {

         // xOffset = event->pos().x() - event->lastPos().x();
          //yOffset = 1;
    }
}

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Complaint:

error: invalid use of undefined type `struct QGraphicsSceneMouseEvent'
error: invalid use of undefined type `struct QGraphicsSceneMouseEvent'

And it points to the lines where prevMousePoint and currMousePoint are. Both variables are of the type QPointF.