How to get the screen size of the device?

Question

The desire have 480 x 800 pixels, 3.7 inches and the HD have 480 x 800 pixels, 4.3 inches screen specification.

I run the code that is accepted as answer from this t

Answer 1

OK FINALLY I found what is my problem

Yes this code works fine but I doesn't return pixels, It returns DIP (Density independent pixels ) which is not the same !

DisplayMetrics dm = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(dm);
int width = dm.widthPixels; //320 dip
int height = dm.heightPixels; //533 dip

What I needed is the REAL pixels and the calculation for them is like this:

int widthPix = (int) Math.ceil(dm.widthPixels * (dm.densityDpi / 160.0));

now the widthPix is 480 !