code: protected void addItemsTo(@Nullable ViewGroup layout) {
          if (layout == null) {
              return;
          }
  
          recycleAllFrom(layout);
  
          for (int pos = 0, size = getCount(); pos < size; pos++) {
              final int viewType = getItemViewType(pos);
              final View view = getView(pos, pollRecycledView(viewType), layout);
              layout.addView(view);
              view.setTag(TAG_TYPE_ID, viewType);
          }
      }
docs: Removes all child views from given view group and fill it in with items populated from this
  adapter.