Here you can find the source of pixelsToDpi(Resources res, int pixels)
public static int pixelsToDpi(Resources res, int pixels)
//package com.java2s; /*/*from www. j a v a 2s. c o m*/ SoftVolume.java Copyright (C) 2011 Belledonne Communications, Grenoble, France This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ import android.content.res.Resources; import android.util.TypedValue; public class Main { public static int pixelsToDpi(Resources res, int pixels) { return (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, (float) pixels, res.getDisplayMetrics()); } }