Pyqt: How-to set item always in the center of a QGraphicsView when scrolling is possible?

Question

Hi,

I have a QGraphicsView. To that I added a QGraphicsScene and to that a added an QPixmap(*.jpeg) and QGraphicsEllipseItem(a circle). The QPixmap is much more bigger than the QGraphicsView, so scrolling is enabled. The problem is that both QPixmap and QGraphicsEllipseItem are moving. But I want a fixed position for the QGraphicsEllipseItem in QGraphicsView. It should always be in the center of the QGraphicsView. How can I do that? Hope someone can help.

Answer 1

Add a signal handler for the scroll signal of the scroll bars (use QAbstractSlider::sliderMoved()).

Then you can query the view for it's left/top offset and size and position the circle accordingly. See the explanation for QAbstractScrollArea to get you started.