code: public View getHeaderAt(int position) {
          if (position == MATCHED_STICKIED_HEADER) {
              return mStickiedHeader;
          }
  
          try {
              return (View)getChildAt(position).getTag();
          } catch (Exception e) {
          }
          return null;
      }
docs: Gets the header at an item position. However, the position must be that
  of a HeaderFiller.
  
  @param position Position of HeaderFiller.
  @return Header View wrapped in HeaderFiller or null if no header was
  found.