code: @NonNull
      public IconicsDrawable sizePxX(@Dimension(unit = PX) int sizePx) {
          mSizeX = sizePx;
          setBounds(0, 0, mSizeX, mSizeY);
  
          invalidateSelf();
          return this;
      }
docs: Set the size of the drawable.
  
  @param sizePx The size in pixels (px).
  @return The current IconicsDrawable for chaining.