如何在本地flutter应用程序中添加“添加到收藏夹”

import 'package:flutter/material.dart';
import 'package:shared_preferences/shared_preferences.dart';

class MyFavoritePage extends StatefulWidget {
  @override
  _MyFavoritePageState createState() => _MyFavoritePageState();
}

class _MyFavoritePageState extends State<MyFavoritePage> {
  List<String> favoriteItems = [];

  @override
  void initState() {
    super.initState();
    loadFavoriteItems();
  }

  Future<void> loadFavoriteItems() async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    List<String> items = prefs.getStringList('favoriteItems') ?? [];
    setState(() {
      favoriteItems = items;
    });
  }

  Future<void> saveFavoriteItems() async {
    SharedPreferences prefs = await SharedPreferences.getInstance();
    await prefs.setStringList('favoriteItems', favoriteItems);
  }

  void addToFavorites(String item) {
    setState(() {
      favoriteItems.add(item);
    });
    saveFavoriteItems();
  }

  void removeFromFavorites(String item) {
    setState(() {
      favoriteItems.remove(item);
    });
    saveFavoriteItems();
  }

  bool isFavorite(String item) {
    return favoriteItems.contains(item);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('My Favorite Items'),
      ),
      body: ListView(
        children: [
          ListTile(
            title: Text('Item 1'),
            trailing: IconButton(
              icon: Icon(
                isFavorite('Item 1') ? Icons.favorite : Icons.favorite_border,
              ),
              onPressed: () {
                if (isFavorite('Item 1')) {
                  removeFromFavorites('Item 1');
                } else {
                  addToFavorites('Item 1');
                }
              },
            ),
          ),
          ListTile(
            title: Text('Item 2'),
            trailing: IconButton(
              icon: Icon(
                isFavorite('Item 2') ? Icons.favorite : Icons.favorite_border,
              ),
              onPressed: () {
                if (isFavorite('Item 2')) {
                  removeFromFavorites('Item 2');
                } else {
                  addToFavorites('Item 2');
                }
              },
            ),
          ),
          // Add more list items as needed
        ],
      ),
    );
  }
}