Java tutorial
//package com.java2s; import android.graphics.Color; public class Main { public static int shadeColor(int color, float shadeAmt) { float[] hsv = new float[3]; Color.RGBToHSV(Color.red(color), Color.green(color), Color.blue(color), hsv); hsv[2] *= (1 - shadeAmt); return Color.HSVToColor(hsv); } }