Hi! I'm using a function of a library which calls a callback function at a certain point. This callback function is defined like:

static void __stdcall function(...);
I'm trying to use Qt classes inside, but it seems it's not working. QMessageBox says I'm not in the GUI thread so I can't create messageboxes. I tried to use QImage and QPixmap, but it seems no image can be loaded. Do you have any idea why?
Thanks!