Quote Originally Posted by TheVirus View Post
I got it working somehow,
Guessing and just pushing buttons until it "works somehow" is not a recipe for a reliable result.

In my other program (C), I used 'extern' to share the struct between files, let's hope Qt acts the same.
Qt is not a programming language. Why do you believe that using a library of routines, like Qt, is going to change the fundamental behaviour of the programming language (C/C++)?