How do I tell when GUI is fully displayed

[Grimface]

I want to display a message to the user after the GUI has been fully displayed. Is there a signal indicating that the GUI is fully shown on the screen?

[JoeCFD]

@Grimface override the showEvent of Mainwindow or your main widget.
https://doc.qt.io/qt-5.15/qwidget.html#showEvent

[Grimface]

@JoeCFD Thanks Joe I'll take a look into that.

[SimonSchroeder]

Slightly different idea: If you know what you are doing call repaint instead of update (update might gather a few calls before actually repainting). If repaint is called from the GUI thread it will block until it is done. So, after repaint returns you'll know that it has completed.

Only don't call repaint too often. This will have really bad performance.