How can QOpenGLWidget update not result in paintGL events?

Question

I'm logging calls to update() and paintGL(), but somehow, only update happens. paintGL is called a couple of times and then never again! How is this possible? The window is visible and isVisible() returns True every time update() is called.

Specifically, I converted from QGLWidget to QOpenGLWidget. I replaced my calls to updateGL() with calls to update(), and I replaced passing the format to the constructor with calling setFormat(). I added various calls to makeCurrent() where appropriate. Is there anything I'm missing?

It appears that QOpenGLWidget might be broken when it is one of many widgets within a window.

Answer 1

My QOpenGLWidget was in a QScrollArea, which was not forwarding QPaint events.