PySide window does not resize to fit screen

[Hedieh Ebrahimi]

Hi Chris, 

Thanks for your answer. I get your point now. 
Unfortunately there are not layouts in my user interface. 
Smaller widget have been grouped using group boxes and then all these group boxes are put on the central widget.

I would like to recreate my user interface using one of the designer software that exist.

Could you recommend any free designer software that I can create my user interface with?

Thank you