How to set DialogFragment’s width and height?

If you convert directly from resources values:

int width = getResources().getDimensionPixelSize(R.dimen.popup_width);
int height = getResources().getDimensionPixelSize(R.dimen.popup_height);        
getDialog().getWindow().setLayout(width, height);

Then specify match_parent in your layout for the dialog:

android:layout_width="match_parent"
android:layout_height="match_parent"

Now you only have to worry about one place (i.e. your DialogFragment.onResume method). It’s not perfect but at least it works for having a RelativeLayout as the root of your dialog’s layout file.