code: public static int getRealLeft(boolean isRtl, int parentLeft, int parentWidth, int left, int width) {
          if (isRtl) {
              // 1, trim the parent's left.
              left -= parentLeft;
              // 2, calculate the RTL left.
              left = parentWidth - width - left;
              // 3, add the parent's left.
              left += parentLeft;
          }
          return left;
      }
docs: Convert left to RTL left if need.
  @param parentLeft parent's left
  @param parentWidth parent's width
  @param left self's left
  @param width self's width
  @return