OK, here's your GUI with layouts. If you resize your original UI inside of Qt Designer, none of the widgets move, so I have specified that most of the spacers have fixed geometry. This keeps the QFrame in the same location no matter what the size of the QMainWindow. If this isn't what you want, then you can change their size policy from Fixed to something else. You can also look at setting the stretch factors for the widgets and spacers so that resize occurs in the proportions you want. Be sure to comment out your own resize code so you can see what the layout itself is doing.

alenn.ui