删除最后一项时AnimatedList抛出错误

AnimatedList _list;
List _data = [];

void deleteLastItem() {
  if (_data.isNotEmpty) {
    _list.removeItem(
      _data.length - 1,
      (context, animation) => _buildItem(_data[_data.length - 1], animation),
    );
    _data.removeLast();
  }
}

Widget _buildItem(String item, Animation<double> animation) {
  return SizeTransition(
    sizeFactor: animation,
    child: ListTile(
      title: Text(item),
    ),
  );
}

void main() {
  // 初始化数据
  _data = ['Item 1', 'Item 2', 'Item 3'];

  runApp(MaterialApp(
    home: Scaffold(
      appBar: AppBar(
        title: Text('Animated List Example'),
      ),
      body: AnimatedList(
        key: GlobalKey<AnimatedListState>(),
        initialItemCount: _data.length,
        itemBuilder: (context, index, animation) =>
            _buildItem(_data[index], animation),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: deleteLastItem,
        child: Icon(Icons.delete),
      ),
    ),
  ));
}