Flutter最佳实践 #

// features/user/data/models/user_model.dart
import 'package:json_annotation/json_annotation.dart';
import '../../domain/entities/user.dart';

part 'user_model.g.dart';

@JsonSerializable()
class UserModel extends User {
  const UserModel({
    required super.id,
    required super.name,
    required super.email,
  });

  factory UserModel.fromJson(Map<String, dynamic> json) => _$UserModelFromJson(json);
  Map<String, dynamic> toJson() => _$UserModelToJson(this);

  User toEntity() {
    return User(
      id: id,
      name: name,
      email: email,
    );
  }

  static UserModel fromEntity(User entity) {
    return UserModel(
      id: entity.id,
      name: entity.name,
      email: entity.email,
    );
  }
}

// features/user/domain/entities/user.dart
class User {
  final String id;
  final String name;
  final String email;

  const User({
    required this.id,
    required this.name,
    required this.email,
  });
}

// features/user/domain/usecases/get_user.dart
import 'package:fpdart/fpdart.dart';
import '../../../../core/error/failure.dart';
import '../repositories/user_repository.dart';
import '../entities/user.dart';

class GetUser {
  final UserRepository repository;

  GetUser(this.repository);

  Future<Either<Failure, User>> call(String userId) async {
    return await repository.getUser(userId);
  }
}

// features/user/presentation/pages/user_page.dart
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import '../bloc/user_bloc.dart';
import '../widgets/user_details.dart';

class UserPage extends StatelessWidget {
  final String userId;

  const UserPage({Key? key, required this.userId}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: Text('User Details')),
      body: BlocProvider(
        create: (context) => UserBloc(
          getUser: context.read<GetUser>(),
        )..add(LoadUser(userId)),
        child: UserPageContent(),
      ),
    );
  }
}

class UserPageContent extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return BlocBuilder<UserBloc, UserState>(
      builder: (context, state) {
        return switch (state) {
          UserInitial() => Center(child: Text('Load user data')),
          UserLoading() => Center(child: CircularProgressIndicator()),
          UserLoaded(:final user) => UserDetails(user: user),
          UserError(:final message) => Center(child: Text(message)),
        };
      },
    );
  }
}

// 使用Equatable简化状态比较
import 'package:equatable/equatable.dart';
import 'package:flutter_bloc/flutter_bloc.dart';

abstract class UserState extends Equatable {
  const UserState();
  
  @override
  List<Object> get props => [];
}

class UserInitial extends UserState {}

class UserLoading extends UserState {}

class UserLoaded extends UserState {
  final User user;

  const UserLoaded(this.user);

  @override
  List<Object> get props => [user];
}

class UserError extends UserState {
  final String message;

  const UserError(this.message);

  @override
  List<Object> get props => [message];
}

// 事件类
abstract class UserEvent extends Equatable {
  const UserEvent();
  
  @override
  List<Object> get props => [];
}

class LoadUser extends UserEvent {
  final String userId;

  const LoadUser(this.userId);

  @override
  List<Object> get props => [userId];
}

// BLoC类
class UserBloc extends Bloc<UserEvent, UserState> {
  final GetUser getUser;

  UserBloc({required this.getUser}) : super(UserInitial()) {
    on<LoadUser>(_onLoadUser);
  }

  Future<void> _onLoadUser(LoadUser event, Emitter<UserState> emit) async {
    emit(UserLoading());
    
    final result = await getUser(event.userId);
    
    result.fold(
      (failure) => emit(UserError(failure.message)),
      (user) => emit(UserLoaded(user)),
    );
  }
}

// providers/user_provider.dart
import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../../domain/usecases/get_user.dart';
import '../models/user.dart';

// 异步提供器
final userProvider = FutureProvider.family<User, String>((ref, userId) async {
  final getUser = ref.watch(getUserUseCaseProvider);
  final result = await getUser(userId);
  return result.fold(
    (failure) => throw Exception(failure.message),
    (user) => user,
  );
});

// 状态提供器
final userStateProvider = StateNotifierProvider<UserNotifier, User?>((ref) {
  return UserNotifier();
});

class UserNotifier extends StateNotifier<User?> {
  UserNotifier() : super(null);

  void setUser(User user) {
    state = user;
  }

  void clearUser() {
    state = null;
  }
}

// Repository提供器
final userRepositoryProvider = Provider<UserRepository>((ref) {
  return UserRepositoryImpl(
    remoteDataSource: ref.watch(remoteDataSourceProvider),
    localDataSource: ref.watch(localDataSourceProvider),
  );
});

// shared/widgets/custom_button.dart
import 'package:flutter/material.dart';

class CustomButton extends StatelessWidget {
  final String text;
  final VoidCallback? onPressed;
  final bool isLoading;
  final ButtonStyle? style;
  final EdgeInsetsGeometry? padding;

  const CustomButton({
    Key? key,
    required this.text,
    this.onPressed,
    this.isLoading = false,
    this.style,
    this.padding,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return SizedBox(
      width: double.infinity,
      child: ElevatedButton(
        onPressed: isLoading ? null : onPressed,
        style: style ??
            ElevatedButton.styleFrom(
              padding: padding ?? EdgeInsets.symmetric(vertical: 16),
              shape: RoundedRectangleBorder(
                borderRadius: BorderRadius.circular(8),
              ),
            ),
        child: isLoading
            ? SizedBox(
                width: 24,
                height: 24,
                child: CircularProgressIndicator(
                  strokeWidth: 2,
                  valueColor: AlwaysStoppedAnimation<Color>(
                    Theme.of(context).colorScheme.onPrimary,
                  ),
                ),
              )
            : Text(
                text,
                style: TextStyle(fontSize: 16, fontWeight: FontWeight.w600),
              ),
      ),
    );
  }
}

// shared/widgets/loading_widget.dart
class LoadingWidget extends StatelessWidget {
  final String? message;

  const LoadingWidget({Key? key, this.message}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          CircularProgressIndicator(),
          if (message != null) ...[
            SizedBox(height: 16),
            Text(message!),
          ],
        ],
      ),
    );
  }
}

// shared/widgets/error_widget.dart
class ErrorWidget extends StatelessWidget {
  final String message;
  final VoidCallback? onRetry;

  const ErrorWidget({
    Key? key,
    required this.message,
    this.onRetry,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Center(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          Icon(
            Icons.error_outline,
            size: 64,
            color: Theme.of(context).colorScheme.error,
          ),
          SizedBox(height: 16),
          Text(
            message,
            style: TextStyle(fontSize: 16),
            textAlign: TextAlign.center,
          ),
          if (onRetry != null) ...[
            SizedBox(height: 16),
            ElevatedButton(
              onPressed: onRetry,
              child: Text('Retry'),
            ),
          ],
        ],
      ),
    );
  }
}

// shared/utils/responsive.dart
import 'package:flutter/material.dart';

class ResponsiveUtil {
  static bool isMobile(BuildContext context) {
    return MediaQuery.of(context).size.width < 600;
  }

  static bool isTablet(BuildContext context) {
    return MediaQuery.of(context).size.width >= 600 &&
        MediaQuery.of(context).size.width < 900;
  }

  static bool isDesktop(BuildContext context) {
    return MediaQuery.of(context).size.width >= 900;
  }

  static double getResponsivePadding(BuildContext context) {
    if (isMobile(context)) {
      return 16.0;
    } else if (isTablet(context)) {
      return 24.0;
    } else {
      return 32.0;
    }
  }
}

// 使用示例
class ResponsiveScreen extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Padding(
        padding: EdgeInsets.all(ResponsiveUtil.getResponsivePadding(context)),
        child: LayoutBuilder(
          builder: (context, constraints) {
            if (constraints.maxWidth < 600) {
              // 移动端布局
              return MobileLayout();
            } else if (constraints.maxWidth < 900) {
              // 平板布局
              return TabletLayout();
            } else {
              // 桌面布局
              return DesktopLayout();
            }
          },
        ),
      ),
    );
  }
}

class MobileLayout extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        Container(height: 200, color: Colors.blue),
        Expanded(child: Container(color: Colors.grey[200])),
      ],
    );
  }
}

class DesktopLayout extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return Row(
      children: [
        Container(width: 250, color: Colors.grey[300]),
        Expanded(
          child: Column(
            children: [
              Container(height: 200, color: Colors.blue),
              Expanded(child: Container(color: Colors.grey[200])),
            ],
          ),
        ),
      ],
    );
  }
}

// shared/constants/app_constants.dart
class AppConstants {
  // API相关
  static const String baseUrl = String.fromEnvironment('BASE_URL', defaultValue: 'https://api.example.com');
  static const Duration apiTimeout = Duration(seconds: 30);
  
  // 存储键名
  static const String tokenKey = 'auth_token';
  static const String userPreferencesKey = 'user_preferences';
  static const String themeModeKey = 'theme_mode';
  
  // 尺寸相关
  static const double smallPadding = 8.0;
  static const double mediumPadding = 16.0;
  static const double largePadding = 24.0;
  
  static const double smallRadius = 4.0;
  static const double mediumRadius = 8.0;
  static const double largeRadius = 16.0;
  
  // 字体大小
  static const double smallFontSize = 12.0;
  static const double mediumFontSize = 16.0;
  static const double largeFontSize = 20.0;
  
  // 动画时长
  static const Duration shortAnimation = Duration(milliseconds: 200);
  static const Duration mediumAnimation = Duration(milliseconds: 300);
  static const Duration longAnimation = Duration(milliseconds: 500);
}

// shared/constants/assets_constants.dart
class AssetConstants {
  // 图片资源
  static const String logo = 'assets/images/logo.png';
  static const String splashBg = 'assets/images/splash_bg.png';
  
  // 图标资源
  static const String icHome = 'assets/icons/home.svg';
  static const String icProfile = 'assets/icons/profile.svg';
  static const String icSettings = 'assets/icons/settings.svg';
  
  // JSON资源
  static const String sampleData = 'assets/data/sample.json';
}

// shared/constants/validation_constants.dart
class ValidationConstants {
  static const String emailRegex = r'^[\w-\.]+@([\w-]+\.)+[\w-]{2,4}$';
  static const int minPasswordLength = 8;
  static const int maxPasswordLength = 128;
  static const String passwordPattern = r'^(?=.*[a-z])(?=.*[A-Z])(?=.*\d)[a-zA-Z\d@$!%*?&]{8,}$';
}

// shared/extensions/string_extensions.dart
extension StringExtensions on String {
  bool isValidEmail() {
    final RegExp emailExp = RegExp(ValidationConstants.emailRegex);
    return emailExp.hasMatch(this);
  }

  bool isValidPassword() {
    if (length < ValidationConstants.minPasswordLength) return false;
    if (length > ValidationConstants.maxPasswordLength) return false;
    
    final RegExp pwdExp = RegExp(ValidationConstants.passwordPattern);
    return pwdExp.hasMatch(this);
  }

  String capitalize() {
    if (isEmpty) return this;
    return this[0].toUpperCase() + substring(1).toLowerCase();
  }

  String truncate(int maxLength) {
    if (length <= maxLength) return this;
    return substring(0, maxLength) + '...';
  }
}

// shared/extensions/context_extensions.dart
import 'package:flutter/material.dart';

extension ContextExtensions on BuildContext {
  // 尺寸相关
  double get screenWidth => MediaQuery.sizeOf(this).width;
  double get screenHeight => MediaQuery.sizeOf(this).height;
  double get statusBarHeight => MediaQuery.paddingOf(this).top;
  double get bottomPadding => MediaQuery.paddingOf(this).bottom;

  // 主题相关
  ThemeData get theme => Theme.of(this);
  TextTheme get textTheme => Theme.of(this).textTheme;
  ColorScheme get colorScheme => Theme.of(this).colorScheme;

  // 导航相关
  void pop<T extends Object>({T? result}) => Navigator.pop(this, result);
  Future<T?> pushNamed<T extends Object>(String routeName, {Object? arguments}) =>
      Navigator.pushNamed<T>(this, routeName, arguments: arguments);
  void pushReplacementNamed(String routeName, {Object? arguments}) =>
      Navigator.pushReplacementNamed(this, routeName, arguments: arguments);

  // 便捷方法
  void showSnackBar(String message, {Color? backgroundColor}) {
    ScaffoldMessenger.of(this).showSnackBar(
      SnackBar(
        content: Text(message),
        backgroundColor: backgroundColor,
      ),
    );
  }
}

// shared/utils/date_time_utils.dart
class DateTimeUtils {
  static String formatToDisplay(DateTime dateTime) {
    return "${dateTime.day}/${dateTime.month}/${dateTime.year}";
  }

  static String formatToTime(DateTime dateTime) {
    return "${dateTime.hour}:${dateTime.minute.toString().padLeft(2, '0')}";
  }

  static String formatToDateTime(DateTime dateTime) {
    return "${formatToDisplay(dateTime)} ${formatToTime(dateTime)}";
  }

  static String getTimeAgo(DateTime dateTime) {
    final now = DateTime.now();
    final difference = now.difference(dateTime);

    if (difference.inDays > 0) {
      return '${difference.inDays}天前';
    } else if (difference.inHours > 0) {
      return '${difference.inHours}小时前';
    } else if (difference.inMinutes > 0) {
      return '${difference.inMinutes}分钟前';
    } else {
      return '刚刚';
    }
  }

  static bool isToday(DateTime dateTime) {
    final today = DateTime.now();
    return dateTime.year == today.year &&
           dateTime.month == today.month &&
           dateTime.day == today.day;
  }
}

// shared/utils/validator_utils.dart
class ValidatorUtils {
  static String? validateEmail(String? value) {
    if (value == null || value.isEmpty) {
      return '请输入邮箱地址';
    }
    if (!value.isValidEmail()) {
      return '请输入有效的邮箱地址';
    }
    return null;
  }

  static String? validatePassword(String? value) {
    if (value == null || value.isEmpty) {
      return '请输入密码';
    }
    if (!value.isValidPassword()) {
      return '密码必须至少8位，包含大小写字母和数字';
    }
    return null;
  }

  static String? validateRequired(String? value, {String fieldName = '此字段'}) {
    if (value == null || value.trim().isEmpty) {
      return '$fieldName不能为空';
    }
    return null;
  }

  static String? validateMinLength(String? value, int minLength, {String fieldName = '此字段'}) {
    if (value == null || value.length < minLength) {
      return '$fieldName至少需要$minLength个字符';
    }
    return null;
  }
}

// core/error/failure.dart
abstract class Failure {
  final String message;

  const Failure(this.message);
}

class ServerFailure extends Failure {
  const ServerFailure(super.message);
}

class CacheFailure extends Failure {
  const CacheFailure(super.message);
}

class NetworkFailure extends Failure {
  const NetworkFailure(super.message);
}

// core/error/exceptions.dart
class ServerException implements Exception {
  final String message;

  ServerException(this.message);
}

class CacheException implements Exception {
  final String message;

  CacheException(this.message);
}

// core/error/error_handler.dart
import 'package:dio/dio.dart';

class ErrorHandler {
  static Failure handle(Object error) {
    if (error is DioException) {
      switch (error.type) {
        case DioExceptionType.connectionTimeout:
        case DioExceptionType.sendTimeout:
        case DioExceptionType.receiveTimeout:
          return const NetworkFailure('网络连接超时');
        case DioExceptionType.badResponse:
          switch (error.response?.statusCode) {
            case 400:
              return const ServerFailure('请求参数错误');
            case 401:
              return const ServerFailure('未授权访问');
            case 403:
              return const ServerFailure('禁止访问');
            case 404:
              return const ServerFailure('请求资源不存在');
            case 500:
            default:
              return const ServerFailure('服务器内部错误');
          }
        case DioExceptionType.cancel:
          return const NetworkFailure('请求被取消');
        case DioExceptionType.connectionError:
        case DioExceptionType.badCertificate:
        case DioExceptionType.unknown:
        default:
          return const NetworkFailure('网络连接错误');
      }
    } else if (error is ServerException) {
      return ServerFailure(error.message);
    } else if (error is CacheException) {
      return CacheFailure(error.message);
    } else {
      return const ServerFailure('未知错误');
    }
  }
}

// main.dart
import 'package:flutter/foundation.dart';

void main() {
  // 设置全局错误处理
  FlutterError.onError = (FlutterErrorDetails details) {
    // 记录错误
    if (kDebugMode) {
      print(details.exceptionAsString());
      print(details.stack);
    }
    
    // 发送错误报告
    // ErrorReportingService.reportError(details);
  };

  // 设置未捕获异常处理
  PlatformDispatcher.instance.onError = (Object error, StackTrace stack) {
    if (kDebugMode) {
      print(error);
      print(stack);
    }
    
    // 发送错误报告
    // ErrorReportingService.reportError(error, stack);
    return true;
  };

  runApp(MyApp());
}

// services/error_reporting_service.dart
class ErrorReportingService {
  static void reportError(Object error, [StackTrace? stack]) {
    // 发送到错误监控服务（如Firebase Crashlytics）
    // FirebaseCrashlytics.instance.recordError(error, stack);
  }
}

// 遵循TDD流程：先写测试再写实现

// 1. 首先写测试
// features/calculator/domain/usecases/add_numbers_test.dart
import 'package:flutter_test/flutter_test.dart';
import 'add_numbers.dart';

void main() {
  late AddNumbers usecase;

  setUp(() {
    usecase = AddNumbers();
  });

  test('should return sum of two positive numbers', () async {
    // arrange
    const tA = 5;
    const tB = 3;
    const tExpected = 8;

    // act
    final result = usecase(tA, tB);

    // assert
    expect(result, equals(tExpected));
  });

  test('should return correct sum when one number is negative', () async {
    // arrange
    const tA = 5;
    const tB = -3;
    const tExpected = 2;

    // act
    final result = usecase(tA, tB);

    // assert
    expect(result, equals(tExpected));
  });
}

// 2. 然后实现功能
// features/calculator/domain/usecases/add_numbers.dart
class AddNumbers {
  int call(int a, int b) {
    return a + b;
  }
}

// 使用Mockito进行依赖模拟
// features/user/data/repositories/user_repository_impl_test.dart
import 'package:flutter_test/flutter_test.dart';
import 'package:mockito/mockito.dart';
import 'package:fpdart/fpdart.dart';
import '../../../../../core/error/failure.dart';
import '../../../domain/entities/user.dart';
import '../../datasources/local/user_local_data_source.dart';
import '../../datasources/remote/user_remote_data_source.dart';
import '../models/user_model.dart';
import '../repositories/user_repository_impl.dart';

class MockRemoteDataSource extends Mock implements UserRemoteDataSource {}
class MockLocalDataSource extends Mock implements UserLocalDataSource {}

void main() {
  late UserRepositoryImpl repository;
  late MockRemoteDataSource mockRemoteDataSource;
  late MockLocalDataSource mockLocalDataSource;

  setUp(() {
    mockRemoteDataSource = MockRemoteDataSource();
    mockLocalDataSource = MockLocalDataSource();
    repository = UserRepositoryImpl(
      remoteDataSource: mockRemoteDataSource,
      localDataSource: mockLocalDataSource,
    );
  });

  group('getUser', () {
    const tUserId = '123';
    final tUserModel = UserModel(
      id: tUserId,
      name: 'Test User',
      email: 'test@example.com',
    );
    final tUser = tUserModel.toEntity();

    test('should return user when call to remote data source is successful', () async {
      // arrange
      when(mockRemoteDataSource.getUser(any))
          .thenAnswer((_) async => tUserModel);

      // act
      final result = await repository.getUser(tUserId);

      // assert
      verify(mockRemoteDataSource.getUser(tUserId));
      expect(result, equals(Right(tUser)));
    });

    test('should cache user locally when get user successfully', () async {
      // arrange
      when(mockRemoteDataSource.getUser(any))
          .thenAnswer((_) async => tUserModel);
      when(mockLocalDataSource.cacheUser(any))
          .thenAnswer((_) async => Future.value());

      // act
      await repository.getUser(tUserId);

      // assert
      verify(mockLocalDataSource.cacheUser(tUserModel));
    });

    test('should return cached user when remote data source fails', () async {
      // arrange
      when(mockRemoteDataSource.getUser(any))
          .thenThrow(ServerException('Server error'));
      when(mockLocalDataSource.getCachedUser(any))
          .thenAnswer((_) async => tUserModel);

      // act
      final result = await repository.getUser(tUserId);

      // assert
      expect(result, equals(Right(tUser)));
    });
  });
}

// 使用const构造函数
class OptimizedWidget extends StatelessWidget {
  const OptimizedWidget({Key? key}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        // 使用const
        title: const Text('Optimized App'),
        // 使用const
        backgroundColor: Colors.blue,
      ),
      body: Column(
        children: const [
          // 使用const列表
          Padding(
            padding: EdgeInsets.all(16.0),
            child: Text('This is an optimized widget tree'),
          ),
          // 其他const子组件
        ],
      ),
    );
  }
}

// 使用Key优化列表
class OptimizedList extends StatelessWidget {
  final List<Item> items;

  const OptimizedList({Key? key, required this.items}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      itemCount: items.length,
      itemBuilder: (context, index) {
        final item = items[index];
        // 使用ValueKey确保每个项目有唯一标识
        return KeyedSubtree(
          key: ValueKey(item.id),
          child: ListTile(
            title: Text(item.title),
            subtitle: Text(item.description),
          ),
        );
      },
    );
  }
}

// 使用RepaintBoundary隔离重绘
class IsolatedRepaintWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return RepaintBoundary(
      child: CustomPaint(
        painter: _CustomPainter(),
        child: Container(
          width: 200,
          height: 200,
          color: Colors.transparent,
        ),
      ),
    );
  }
}

class _CustomPainter extends CustomPainter {
  @override
  void paint(Canvas canvas, Size size) {
    // 绘制逻辑
  }

  @override
  bool shouldRepaint(covariant CustomPainter oldDelegate) => false;
}

// 正确管理资源释放
class ResourceManagementWidget extends StatefulWidget {
  @override
  _ResourceManagementWidgetState createState() => _ResourceManagementWidgetState();
}

class _ResourceManagementWidgetState extends State<ResourceManagementWidget> {
  Timer? _timer;
  StreamSubscription? _subscription;
  AnimationController? _animationController;

  @override
  void initState() {
    super.initState();
    
    // 初始化资源
    _timer = Timer.periodic(Duration(seconds: 1), (timer) {
      setState(() {});
    });
    
    _subscription = Stream.periodic(Duration(seconds: 2)).listen((event) {
      print('Event: $event');
    });
    
    _animationController = AnimationController(
      duration: Duration(seconds: 1),
      vsync: this,
    );
  }

  @override
  void dispose() {
    // 正确释放所有资源
    _timer?.cancel();
    _subscription?.cancel();
    _animationController?.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Container();
  }
}

// injection_container.dart
import 'package:get_it/get_it.dart';
import 'package:injectable/injectable.dart';
import 'package:http/http.dart' as http;
import 'core/service_locator.config.dart';

final getIt = GetIt.instance;

@InjectableInit(
  initializerName: r'$initGetIt', 
  preferRelativeImports: true,
  asExtension: false,
)
void configureDependencies() => $initGetIt(getIt);

// 配置类
@module
abstract class RegisterModule {
  @lazySingleton
  http.Client get httpClient => http.Client();

  @lazySingleton
  NetworkInfo get networkInfo => NetworkInfoImpl();
}

// services/secure_storage_service.dart
import 'package:flutter_secure_storage/flutter_secure_storage.dart';

class SecureStorageService {
  static final _storage = FlutterSecureStorage();

  static Future<void> writeSecureData(String key, String value) async {
    await _storage.write(key: key, value: value);
  }

  static Future<String?> readSecureData(String key) async {
    return await _storage.read(key: key);
  }

  static Future<void> deleteSecureData(String key) async {
    await _storage.delete(key: key);
  }

  static Future<void> clearAllSecureData() async {
    await _storage.deleteAll();
  }
}

// services/api_service.dart
import 'package:dio/dio.dart';

class ApiService {
  final Dio _dio;

  ApiService(this._dio) {
    // 配置安全相关的拦截器
    _dio.interceptors.add(
      InterceptorsWrapper(
        onRequest: (options, handler) async {
          // 添加认证头
          final token = await SecureStorageService.readSecureData('auth_token');
          if (token != null) {
            options.headers['Authorization'] = 'Bearer $token';
          }
          
          // 添加安全头
          options.headers['X-Requested-With'] = 'XMLHttpRequest';
          
          handler.next(options);
        },
        onResponse: (response, handler) {
          // 检查响应安全
          if (response.statusCode == 401) {
            // 处理认证失败
            SecureStorageService.deleteSecureData('auth_token');
          }
          handler.next(response);
        },
        onError: (DioException err, handler) {
          // 统一错误处理
          handler.next(err);
        },
      ),
    );
  }
}

// l10n/app_localizations.dart (Generated)
import 'package:flutter/material.dart';
import 'package:flutter_gen/gen_l10n/app_localizations.dart';

// 使用示例
class LocalizedWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context)!;
    
    return Scaffold(
      appBar: AppBar(
        title: Text(l10n.appTitle),
      ),
      body: Center(
        child: Text(l10n.helloWorld),
      ),
    );
  }
}