code: public ViewHolder getChildViewHolder(View child) {
          final ViewParent parent = child.getParent();
          if (parent != null && parent != this) {
              throw new IllegalArgumentException("View " + child + " is not a direct child of " +
                      this);
          }
          return getChildViewHolderInt(child);
      }
docs: Retrieve the {@link com.twotoasters.android.support.v7.widget.RecyclerView.ViewHolder} for the given child view.
  
  @param child Child of this RecyclerView to query for its ViewHolder
  @return The child view's ViewHolder