How to get screen display metrics in application class

Question

If I put this in some activity class it works perfectly but, when I put it in my App class the method getWindowManager() can not be found. Is there some way to

Answer 1

final DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);

int width = dm.widthPixels;
int height = dm.heightPixels;

getWindow().setLayout((int) (width * .8), (int) (height * .5));