public T lastItem() {
        if (mDataList == null || mDataList.size() == 0) {
            return null;
        }
        return mDataList.get(mDataList.size() - 1);
    }
public T lastItem() {
        if (mDataList == null || mDataList.size() == 0) {
            return null;
        }
        return mDataList.get(mDataList.size() - 1);
    }
public T lastItem ( ) { if ( mDataList == null || mDataList . size ( ) == 0 ) { return null ; } return mDataList . get ( mDataList . size ( ) - 1 ) ; }
the last item in list

@return
the last item in list