Programmatic QGraphicsView scrolling not updating properly

Question

I have a custom class derived from QGraphicsView that implements a slot call scrollHorizontal(int dx), inside the code is simply

void CustomView::scrollHoriz         


        

Answer 1

I've worked with QGraphicsView in Qt 4.6.3 - 4.7.2 and have to argue that you can use the respective QScrollBar in the following way:

//graphics view initialization
QGraphicsView *graphicsView = new QGraphicsView(parent);
QGraphicsScene *scene = new QGraphicsScene(0,0,widthOfScene,heightOfScene,parent);
graphicsView->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
graphicsView->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
graphicsView->setScene(scene);

//in another method
QScrollBar* yPos=graphicsView->verticalScrollBar();
yPos->setValue((int) newValue);

It does not matter if they are hidden or not. They will still respond to setValue(int) as long as you have a graphics scene that is larger than the graphics view.

The QGraphicsView will also respond to ensureVisible, which moves the scrollbars to the appropriate location.