如何在Flutter中清除AnimatedList表中的所有项目

import 'package:flutter/material.dart';

class AnimatedListExample extends StatefulWidget {
  @override
  _AnimatedListExampleState createState() => _AnimatedListExampleState();
}

class _AnimatedListExampleState extends State<AnimatedListExample> {
  final GlobalKey<AnimatedListState> _listKey = GlobalKey<AnimatedListState>();
  List<String> _items = ['Item 1', 'Item 2', 'Item 3'];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Animated List Example'),
      ),
      body: AnimatedList(
        key: _listKey,
        initialItemCount: _items.length,
        itemBuilder: (context, index, animation) {
          return _buildItem(_items[index], animation);
        },
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.clear_all),
        onPressed: () {
          _clearList();
        },
      ),
    );
  }

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

  void _clearList() {
    final length = _items.length;
    for (int i = length - 1; i >= 0; i--) {
      _removeItem(i);
    }
  }

  void _removeItem(int index) {
    final removedItem = _items.removeAt(index);
    AnimatedListRemovedItemBuilder builder = (context, animation) {
      return _buildItem(removedItem, animation);
    };
    _listKey.currentState.removeItem(index, builder);
  }
}

void main() {
  runApp(MaterialApp(
    home: AnimatedListExample(),
  ));
}