我使用我的应用程序jwt认证。我有带有块模式的主页,该页面选择页面以将其加载到屏幕上(LoginScreen或AppScreen)。 LoginScreen有自己的块模式,也有AppScreen。 当我输入登录名和密码并单击登录时,将调度LoginEvent,该请求将请求发送到Web服务并获得带有jwt令牌的响应,该令牌将存储在共享首选项中,但与此同时,AppScreen会用其bloc呈现。 AppScreen的时间块正在发送数据请求(需要jwt令牌),但会为null,因为尚未存储jwt令牌。我发现一种解决方法不是一种优雅的方法,也可以使用延迟,但这不是正确的方法...
为AppScreen解决:
@override
void initState() {
super.initState();
_bloc = BottomNavigationBloc(workoutTypeRepository: WorkoutTypeRepository());
_bloc.add(AppScreenLunched());
_bloc.add(AppScreenLunched());
}
如果我离开_bloc.add(AppScreenLunched());
的数据无法加载到Homepage,因为它从Web服务接收到空值
如果我离开
_bloc.add(AppScreenLunched());
_bloc.add(AppScreenLunched());
第一个add
数据为空
add
秒之后,我最终获得了随bloc一起提供给首页的数据
有什么办法吗?
开始屏幕:
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
AuthBloc _authBloc;
LoginRepository _loginRepository;
@override
void initState() {
super.initState();
_loginRepository = LoginRepository();
_authBloc = AuthBloc(loginRepository: _loginRepository);
_authBloc.add(AppStarted());
}
@override
void dispose() {
super.dispose();
_authBloc.close();
}
@override
Widget build(BuildContext context) {
return BlocProvider<AuthBloc>(
create: (_) => _authBloc,
child: MaterialApp(
title: 'TEST',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: BlocBuilder(
bloc: _authBloc,
builder: (BuildContext context, AuthState state) {
if (state is AuthUninitialized) {
return LoginPage(loginRepository: _loginRepository);
} else if (state is AuthAuthenticated) {
return AppScreen();
} else if (state is AuthUnauthenticated) {
return LoginPage(loginRepository: _loginRepository);
} else if (state is AuthLoading) {
return LoadingIndicator();
}
return LoginPage(loginRepository: _loginRepository);
}
)
)
);
}
}
LoginScreen(部分):
class LoginForm extends StatefulWidget {
@override
_LoginFormState createState() => _LoginFormState();
}
class _LoginFormState extends State<LoginForm> {
final _emailController = TextEditingController();
final _passwordController = TextEditingController();
final registerRepository = RegisterRepository();
LoginBloc _loginBloc;
@override
void initState() {
super.initState();
_loginBloc = BlocProvider.of<LoginBloc>(context);
}
@override
void dispose() {
super.dispose();
_loginBloc.close();
}
@override
Widget build(BuildContext context) {
_onLoginButtonPressed() {
_loginBloc.add(LoginButtonPressed(
email: _emailController.text,
password: _passwordController.text,
));
}
AppScreen:
class AppScreen extends StatefulWidget {
@override
_AppScreenState createState() => _AppScreenState();
}
class _AppScreenState extends State<AppScreen> {
BottomNavigationBloc _bloc;
@override
void initState() {
super.initState();
_bloc = BottomNavigationBloc(workoutTypeRepository: WorkoutTypeRepository());
_bloc.add(AppScreenLunched());
_bloc.add(AppScreenLunched());
}
@override
void dispose() {
super.dispose();
_bloc.close();
}
@override
Widget build(BuildContext context) {
return BlocProvider<BottomNavigationBloc>(
create: (_) => _bloc,
child: BlocBuilder(
bloc: _bloc,
builder: (BuildContext context, BottomNavigationState state) {
return Scaffold(
appBar: AppBar(
title: Text('TEST'),
),
body: _blocBuilder(context, state),
bottomNavigationBar: BottomActionBar(),
);
},
),
);
}
Widget _blocBuilder(BuildContext context, BottomNavigationState state) {
if (state is PageLoading) {
return Center(child: CircularProgressIndicator());
} else if (state is HomePageLoaded) {
return HomePage(workoutTypes: state.workoutTypes);
} else if (state is SearchPageLoaded) {
return Center(child: Text("SearchPage"));
// return SearchPage();
} else if (state is WorkoutPageLoaded) {
// return Center(child: Text("WorkoutPage"));
return WorkoutPage();
} else if (state is FavoritePageLoaded) {
return Center(child: Text("FavoritePage"));
// return SearchPage();
} else if (state is ProfilePageLoaded) {
return Center(child: Text("ProfilePage"));
// return ProfilePage();
}
return Container();
}
}
AuthBloc:
class AuthBloc extends Bloc<AuthEvent, AuthState> {
final LoginRepository loginRepository;
AuthBloc({@required this.loginRepository}) : assert(loginRepository != null);
@override
AuthState get initialState => AuthUninitialized();
@override
Stream<AuthState> mapEventToState(
AuthEvent event,
) async* {
if (event is AppStarted) {
final bool hasToken = await loginRepository.hasToken();
if (hasToken) {
yield AuthAuthenticated();
} else {
yield AuthUnauthenticated();
}
}
if (event is LoggedIn) {
final bool hasToken = await loginRepository.hasToken();
if (hasToken) {
yield AuthAuthenticated();
} else {
yield AuthUnauthenticated();
}
}
if (event is LoggedOut) {
yield AuthLoading();
await loginRepository.deleteToken();
yield AuthUnauthenticated();
}
}
}
LoginBloc:
class LoginBloc extends Bloc<LoginEvent, LoginState> {
final LoginRepository loginRepository;
final AuthBloc authBloc;
LoginBloc({
@required this.loginRepository,
@required this.authBloc,
}) : assert(loginRepository != null),
assert(authBloc != null);
LoginState get initialState => LoginInitial();
@override
Stream<LoginState> mapEventToState(LoginEvent event) async* {
if (event is LoginButtonPressed) {
yield LoginLoading();
try {
await loginRepository.authenticate(
email: event.email,
password: event.password,
);
authBloc.add(LoggedIn());
yield LoginInitial();
} catch (error) {
yield LoginFailure(error: error.toString());
}
}
}
}
BottomNavigationBarBloc:
class BottomNavigationBloc extends Bloc<BottomNavigationEvent, BottomNavigationState> {
int currentIndex = 0;
final WorkoutTypeRepository workoutTypeRepository;
BottomNavigationBloc({this.workoutTypeRepository}) : assert(workoutTypeRepository != null);
@override
BottomNavigationState get initialState => PageLoading();
@override
Stream<BottomNavigationState> mapEventToState(BottomNavigationEvent event) async* {
if (event is AppScreenLunched) {
this.add(PageTapped(index: this.currentIndex));
}
if (event is PageTapped) {
this.currentIndex = event.index;
yield CurrentIndexChanged(currentIndex: this.currentIndex);
yield PageLoading();
if (this.currentIndex == 0) {
final workoutTypes = await getWorkoutType();
yield HomePageLoaded(workoutTypes: workoutTypes);
}
if (this.currentIndex == 1) {
yield SearchPageLoaded();
}
if (this.currentIndex == 2) {
yield WorkoutPageLoaded();
}
if (this.currentIndex == 3) {
yield FavoritePageLoaded();
}
if (this.currentIndex == 4) {
yield ProfilePageLoaded();
}
}
}
Future<List<WorkoutType>> getWorkoutType() async {
List<WorkoutType> workoutType = await workoutTypeRepository.getWorkoutType();
return workoutType;
}
}
答案 0 :(得分:0)
主页:
class MyApp extends StatefulWidget {
@override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
AuthBloc _authBloc;
LoginRepository _loginRepository;
@override
void initState() {
super.initState();
_loginRepository = LoginRepository();
_authBloc = AuthBloc(loginRepository: _loginRepository);
_authBloc.add(AppStarted());
}
@override
void dispose() {
super.dispose();
_authBloc.close();
}
@override
Widget build(BuildContext context) {
return BlocProvider<AuthBloc>(
create: (context) => _authBloc,
child: MaterialApp(
title: 'TEST',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: BlocBuilder(
bloc: _authBloc,
builder: (BuildContext context, AuthState state) {
if (state is AuthUninitialized) {
return LoadingIndicator();
// return LoginPage(loginRepository: _loginRepository);
} else if (state is AuthAuthenticated) {
return AppScreen();
} else if (state is AuthUnauthenticated) {
return LoginPage(loginRepository: _loginRepository);
} else if (state is AuthLoading) {
return LoadingIndicator();
}
return LoginPage(loginRepository: _loginRepository);
}
)
)
);
}
}
登录页面:
class LoginPage extends StatelessWidget {
final LoginRepository loginRepository;
LoginPage({
Key key,
@required this.loginRepository
}) : assert(loginRepository != null), super(key: key);
@override
Widget build(BuildContext context) {
return Scaffold(
body: BlocProvider(
create: (context) {
return LoginBloc(
loginRepository: loginRepository,
authBloc: BlocProvider.of<AuthBloc>(context)
);
},
child: Stack(
children: <Widget>[
new Container(
decoration: BoxDecoration(
image: backgroundImage
)
),
new Center(
child: SingleChildScrollView(
child: Column(
children: <Widget>[
LoginForm()
]
),
),
)
],
),
)
);
}
}
AuthBloc:
class AuthBloc extends Bloc<AuthEvent, AuthState> {
final LoginRepository loginRepository;
AuthBloc({@required this.loginRepository}) : assert(loginRepository != null);
@override
AuthState get initialState => AuthUninitialized();
@override
Stream<AuthState> mapEventToState(
AuthEvent event,
) async* {
if (event is AppStarted) {
final bool hasToken = await loginRepository.hasToken();
if (hasToken) {
yield AuthAuthenticated();
} else {
yield AuthUnauthenticated();
}
}
if (event is LoggedIn) {
final bool hasToken = await loginRepository.hasToken();
if (hasToken) {
yield AuthAuthenticated();
} else {
yield AuthUnauthenticated();
}
}
if (event is LoggedOut) {
yield AuthLoading();
await loginRepository.deleteToken();
yield AuthUnauthenticated();
}
}
}
LoginBloc:
class LoginBloc extends Bloc<LoginEvent, LoginState> {
final LoginRepository loginRepository;
final AuthBloc authBloc;
LoginBloc({
@required this.loginRepository,
@required this.authBloc,
}) : assert(loginRepository != null),
assert(authBloc != null);
LoginState get initialState => LoginInitial();
@override
Stream<LoginState> mapEventToState(LoginEvent event) async* {
if (event is LoginButtonPressed) {
yield LoginLoading();
try {
await loginRepository.authenticate(
email: event.email,
password: event.password,
);
authBloc.add(LoggedIn());
yield LoginInitial();
} catch (error) {
yield LoginFailure(error: error.toString());
}
}
}
}
登录存储库:
class LoginRepository {
LoginProvider _loginProvider;
LoginRepository({LoginProvider loginProvider}) {
_loginProvider = loginProvider ?? LoginProvider();
}
Future<String> authenticate({String email, String password}) async {
if (email == null || password == null) {
return "Nie podanu loginu lub hasła";
}
var loginData =
await _loginProvider.login(email: email, password: password);
var token = AuthToken.fromJson(loginData);
return token.accessToken;
}
Future<bool> hasToken() async {
String token = await LocalStorage.get(Constant.ACCESS_TOKEN);
if (token != null) {
return true;
}
return false;
}
Future<void> persistToken(String token) async {
if (token != null) {
await LocalStorage.save(Constant.ACCESS_TOKEN, "${Constant.TOKEN_TYPE_BEARER} $token");
}
}
Future<void> deleteToken() async {
await LocalStorage.remove(Constant.ACCESS_TOKEN);
}
}
LocalStorage:
class LocalStorage {
static save(String key, String value) async {
SharedPreferences prefs = await SharedPreferences.getInstance();
prefs.setString(key, value);
}
static Future<String> get(String key) async {
SharedPreferences prefs = await SharedPreferences.getInstance();
return prefs.get(key);
}
static remove(String key) async {
SharedPreferences prefs = await SharedPreferences.getInstance();
prefs.remove(key);
}
static removeAll() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
var keys = prefs.getKeys();
keys.map((key) {
remove(key);
});
}
}