<![CDATA[Triggering drawForeground and drawBackground]]>Re: [SOLVED]Qt 5.2.1 GraphicsView::drawBackground and drawForeground are not called after GraphicsView::Update()

I have been looking for a way to trigger drawForground after updating properties on mouse move, first I was using update() method of graphics scene, it worked prefectly, but I didn't want to trigger and entire update every time the mouse moved in my case (a selection box)

anyhow, I found the solution in documentation and it worked perfectly
https://doc.qt.io/qt-6/qgraphicsscene.html#invalidate

now I call this everytime I want to trigger only the forground layer redraw
self.invalidate(self.sceneRect(), QGraphicsScene.ForegroundLayer)

best regrads,
Iyad

]]>https://forum.qt.io/topic/139549/triggering-drawforeground-and-drawbackgroundRSS for NodeFri, 06 Nov 2026 17:15:20 GMTSat, 24 Sep 2022 22:17:33 GMT60<![CDATA[Reply to Triggering drawForeground and drawBackground on Sun, 25 Sep 2022 12:34:00 GMT]]>There's a catch though, graphics_scene.update() makes the forground drawn even outside the boundaries of the scene, which is what I desired in my case, invalidate with scene rect doesn't, because it is limited to the rect we pass to it

]]>https://forum.qt.io/post/730103https://forum.qt.io/post/730103Sun, 25 Sep 2022 12:34:00 GMT