Updating drawing in qt

[mrdanbrooks]

Block text does not update correctly.

This is because we reuse blocks if the index value is still needed. We do however reassign values to blocks such as the text that should be drawn with them. But Qt does not understand that the text value changed, so it doesn't repaint until you zoom or resize the window.

This can be manually specified by either telling the view to redraw everything every time using

setViewportUpdateMode(QGraphicsView.FullViewportUpdate)

inside the QtView - but this is very inefficient. Alternatively, we can call

update(self.rect())

inside the BlockItem's set_attributes() function. This works but does not update text that spills outside the box.