float dp = 25;
//방법1
int pixels1 = (int) TypedValue.applyDimension(
TypedValue.COMPLEX_UNIT_DIP, dp, getResources().getDisplayMetrics());
//방법2
DisplayMetrics metrics = getResources().getDisplayMetrics();
float fpixels = metrics.density * dp;
int pixels2 = (int) (fpixels + 0.5f);
//방법3
float pixels3 = getResources().getDimensionPixelSize(R.dimen.dip);
Log.e("functionPixel",pixels1+"");
Log.e("metricsPixel",pixels2+"");
Log.e("diemPixel",pixels3+"");
