code: public static void setBackground(EfficientCacheView cacheView, int viewId, Drawable drawable) {
          View view = cacheView.findViewByIdEfficient(viewId);
          if (view != null) {
              if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN) {
                  view.setBackgroundDrawable(drawable);
              } else {
                  view.setBackground(drawable);
              }
          }
      }
docs: Equivalent to calling View.setBackground
  
  @param cacheView The cache of views to get the view from
  @param viewId    The id of the view whose background should change
  @param drawable  The new background for the view