Right-click on My Computer-Properties-Advanced System Settings-Environment Variables-(User Variables).
Create a new variable name: QT_SCALE_FACTOR.
Variable value: 1 or 1.25 or 1.5 (corresponding to the interface magnification, you can try them all), and then confirm them all the way. Reopen Qt Creator to see the interface size you want.
Effective range:
System-level shortcut keys can respond globally, and they can work no matter where the current focus is and what programs are running.
Application-level hotkeys only work in the currently active program. Hotkeys are invalid when the definition program to which they are applied is inactive or running in the background.
Control-level hotkeys are only valid in the current control.
Shortcuts for general systems and applications can be customized according to their own operating habits.