public boolean addItems(Collection<T> items) {
        if (items.isEmpty()) return false;
        int previousSize = getItemCount();
        if (mListItems.addAll(items)) {
            notifyItemRangeInserted(previousSize, items.size());
            return true;
        }
        return false;
    }
public boolean addItems ( Collection < T > items ) { if ( items . isEmpty ( ) ) return false ; int previousSize = getItemCount ( ) ; if ( mListItems . addAll ( items ) ) { notifyItemRangeInserted ( previousSize , items . size ( ) ) ; return true ; } return false ; }
Append a collection of items and refresh the {@code RecyclerView} by calling
{@code notifyItemRangeInserted()}.

@param items collection of items to append
@return true if any data was modified by this operation, false otherwise.