Here you can find the source of px2dip(Context context, float pxValue)
public static int px2dip(Context context, float pxValue)
//package com.java2s; import android.content.Context; public class Main { /**/*from w w w . jav a 2 s . c o m*/ * px to dip */ public static int px2dip(Context context, float pxValue) { final float scale = context.getResources().getDisplayMetrics().density; return (int) (pxValue / scale + 0.5f); } }