code: public static int[] getColorsFromArrayRes(Resources resources, int resId) {
          try {
              @SuppressLint("Recycle")
              TypedArray array = resources.obtainTypedArray(resId);
              if (array.length() > 0) {
                  final int len = array.length();
                  final int[] colors = new int[len];
                  for (int i = 0; i < len; i++) {
                      colors[i] = array.getColor(i, 0);
                  }
                  return colors;
              }
          } catch (Resources.NotFoundException ignored) {
          }
          return null;
      }
docs: Get color array values form array resource
  
  @param resources Resources
  @param resId     Resources id
  @return color array