问题
Can I set the QT_AUTO_SCREEN_SCALE_FACTOR 1 behavior via an API call rather than by the environment variable? I want to detect if my Qt application is running on a high dpi screen, then set the scaling accordingly.
I have tried to set it at the very beginning of main, which does not work
QProcessEnvironment::systemEnvironment().insert("QT_AUTO_SCREEN_SCALE_FACTOR", "1");
It's meant to be used along with QProcess, to set the environment for child processes. It cannot be used to change the current process's environment.
Follow up of Style sheets / Qt Designer support for high dpi screens?
回答1:
The following should work
qputenv("QT_AUTO_SCREEN_SCALE_FACTOR", "1");
来源：https://stackoverflow.com/questions/35877420/can-i-set-qt-auto-screen-scale-factor-behavior-via-api