Flutter :如何记住和突出显示所选的抽屉项目？

import 'package:flutter/material.dart';

class MyDrawer extends StatefulWidget {
  @override
  _MyDrawerState createState() => _MyDrawerState();
}

class _MyDrawerState extends State<MyDrawer> {
  int _selectedIndex = 0; // 保存所选项目的索引值

  void _onItemTapped(int index) {
    setState(() {
      _selectedIndex = index; // 更新所选项目的索引值
    });
  }

  @override
  Widget build(BuildContext context) {
    return Drawer(
      child: ListView(
        padding: EdgeInsets.zero,
        children: <Widget>[
          ListTile(
            title: Text('项目1'),
            selected: _selectedIndex == 0, // 判断是否选中
            onTap: () => _onItemTapped(0),
          ),
          ListTile(
            title: Text('项目2'),
            selected: _selectedIndex == 1,
            onTap: () => _onItemTapped(1),
          ),
          ListTile(
            title: Text('项目3'),
            selected: _selectedIndex == 2,
            onTap: () => _onItemTapped(2),
          ),
        ],
      ),
    );
  }
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(
          title: Text('Flutter抽屉示例'),
        ),
        drawer: MyDrawer(), // 使用自定义的抽屉布局
        body: Center(
          child: Text('主要内容'),
        ),
      ),
    );
  }
}

void main() {
  runApp(MyApp());
}