The idea is that you have your container widget getting resized and in its resize event, you change the size of the inner widgets with the ratio you want.

OK here we go. All the files are in DropBox and should be available via: https://www.dropbox.com/sh/7hzpv4k021k50y2/AACobsU7FpvbllB_56UUffP5a?dl=0 I have hardcoded a minimal data set which is accessed by clicking on the Load button - so as to keep the system as intended. No other buttons work.