I got a QMainWindow, and from that i run a QDialog named MyDialog and when MyDialog is displayed and a user clicks the backgroun main window, the QDialog is destroyed or something.. how can i detect that ?

I have tried this:
connect(MyDialog,SIGNAL(destroyed()),process,SLOT( stop()));

But it does not work..

Any ideas?

I'm not sure about your problem but you could use QDialog's finished signal or reimplement closeEvent.

Edit: Been doing too much desktop applications lately => Removed incorrect advice

Thank you, but the finish signal does not work. I dont want to reimplement anything, I just want a simple dialog with some user input.

The dialog gets disposed of with a DialogCode of None if you tap on the background form when a modal QDialog is being displayed.

You have to handle accept() / reject() yourself from whatever buttons are on your form. When the background is clicked it is being "canceled" without being rejected.