@@ -0,0 +1,323 @@
+package com.roly.nfc.crypto.util;%0A%0Aimport android.graphics.Color;%0A%0Apublic class ColorUtils %7B%0A%0A    private ColorUtils()%7B%7D%0A%0A    public static int darken(int color, float value) %7B%0A        float%5B%5D hsv = new float%5B3%5D;%0A        Color.colorToHSV(color, hsv);%0A        hsv%5B2%5D *= value;%0A        return Color.HSVToColor(hsv);%0A    %7D%0A%0A%7D%0A

Add ColorUtils class