QDialog: show() and exec() together in constructor?

[wysota]

processEvents() processes all events pending. The problem widgets are not painted is because you made the processor very busy. Instead use slots that'll get triggered every 100ms or so - the task will do its job slower, but the system stability will be sustained.

[Teuniz]

I will use the solution with the QTimer, it gives better results than using qApp->processEvents();

Thanks for your help.