Document that dragMoveEvent() always needs to be re-implemented for custom drop handling in QGraphicsView

I'm doing dropping to the QGraphicsView some data.

I successfully receive dragEnterEvent( QDragEnterEvent * event ) and here accept action with event->acceptProposedAction().

But I don't receive dropEvent on dropping and cursor shows that my view doesn't accept drop.

This works well with QWidget but doesn't with QGraphicsView.

In the attached sample try to drag and drop something to the view...