embedded - How to force redraw/update QT eglfs top-level widget?

Question

I have very simple QT application using eglfs platform plugin, so it's works like a charm on very common SoC. QT renders output directly to framebuffer.

Because of some peculiarity, content of framebuffer can be erased outside of QT app. In this case I want to force top-level widget to redraw .

Unfortunately all available snippets not works for me:

 repaint();
 update();
 update(geometry());
 ...etc

Only one exception is sequential call of setWindowOpacity(0), and then setWindowOpacity(1.0); Perhaps it works, but I don't like such solution because overkill and unnecessary flickering.

So please suggest me how to properly force eglfs window to repaint immediately.

Will be grateful for any help.

Answer 1

等待大神解答