如何从一个flutter项目中制作多个主题应用程序？

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

// 创建多个主题数据
class AppTheme {
  final String name;
  final ThemeData themeData;

  AppTheme({required this.name, required this.themeData});
}

final List<AppTheme> themes = [
  AppTheme(
    name: 'Light',
    themeData: ThemeData.light(),
  ),
  AppTheme(
    name: 'Dark',
    themeData: ThemeData.dark(),
  ),
];

void main() {
  runApp(
    ChangeNotifierProvider(
      create: (context) => ThemeProvider(),
      child: MyApp(),
    ),
  );
}

class ThemeProvider with ChangeNotifier {
  int _currentThemeIndex = 0;

  // 定义主题切换方法
  void toggleTheme() {
    _currentThemeIndex = (_currentThemeIndex + 1) % themes.length;
    notifyListeners();
  }

  // 获取当前主题数据
  ThemeData get currentTheme => themes[_currentThemeIndex].themeData;
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      // 使用主题数据
      theme: Provider.of<ThemeProvider>(context).currentTheme,
      home: Scaffold(
        appBar: AppBar(
          title: Text('Flutter Theme Demo'),
        ),
        body: Center(
          child: Column(
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Text('Hello, World!'),
              ElevatedButton(
                onPressed: () {
                  // 切换主题
                  Provider.of<ThemeProvider>(context, listen: false)
                      .toggleTheme();
                },
                child: Text('Toggle Theme'),
              ),
            ],
          ),
        ),
      ),
    );
  }
}