Hi,
I see you opened Problem using TThread with PyROOT to discuss the “threaded python” issue further.
I don’t know what to say - you are adding lots of complexity to your problem (combining python and C++; and much worse: with threading!) and then asking for a simple solution…
If you indeed want to use the GUI I can warmly recommend you to stay on the C++ side.
Cheers, Axel.