我刚刚按照迁移指南将 FireBase 插件升级到最新版本https://firebase.flutter.dev/docs/migration https://firebase.flutter.dev/docs/migration并开始注意到，每当我进行热重载时，我的应用程序都会进行热重启并返回到初始路线。首先我认为这可能是 Android Studio 问题，所以我也尝试通过命令提示符和 VS code，但结果相同。我搜索了与该主题相关的旧 Stackoverflow 问题，但找不到任何可以解决该问题的内容。
我正在复制下面的代码。
PS：我对 Flutter 还很陌生，这是我在 stackoverflow 上遇到的第一个问题。
非常感谢任何帮助。
编辑：刚刚调试它，发现执行热重载时它会返回到 runApp(...) 。
main.dart
void main() async {
String authMethod;
WidgetsFlutterBinding.ensureInitialized();
SharedPreferenceService localStorage = SharedPreferenceService();
authMethod = await localStorage.getAuthMode();
print("Authentication Mode $authMethod");
setupLocator();
runApp(
DevicePreview(
enabled: false,//kReleaseMode,
builder: (context)=>AppInitialization())
);
}
应用程序初始化.dart
class AppInitialization extends StatelessWidget {
final Future<FirebaseApp> _initialization = Firebase.initializeApp();
@override
Widget build(BuildContext context) {
return FutureBuilder(
future: _initialization,
builder: (context, snapshot) {
if (snapshot.hasError) {
return Center(
child: Container(
child: Text('Unable to Initialize FireBase'),
),
);
}
if (snapshot.connectionState == ConnectionState.done) {
print("======= F I R E B A S E A P P ========");
return LocalGroceryOnline();
}
return Center(
child: SizedBox(
height: 40,
width: 40,
child: CircularProgressIndicator(
strokeWidth: 2.0,
valueColor: AlwaysStoppedAnimation<Color>(Colors.redAccent, )),
),
);
});
}
}
本地杂货在线.dart
class LocalGroceryOnline extends StatelessWidget {
final GlobalKey<NavigatorState> navigatorKey = new GlobalKey<NavigatorState>();
@override
Widget build(BuildContext context) {
return MultiProvider (
providers: [
Provider<FirebaseAuthService>(create: (_) => FirebaseAuthService()),
Provider<SignInHelperService>(create: (_) => SignInHelperService()),
Provider<SharedPreferenceService>(create: (_) => SharedPreferenceService()),
ChangeNotifierProvider<CartModel>(create: (_) => CartModel()),
ChangeNotifierProvider<UserModel>(create: (_) => UserModel()),
ChangeNotifierProvider<ProductModel>(create: (_) => ProductModel()),
ChangeNotifierProvider<cat.Category>(create: (_) => cat.Category()),
ChangeNotifierProvider<AppSetting>(create: (_) => AppSetting()),
ChangeNotifierProvider<ValueNotifier<bool>>(create: (_) => ValueNotifier<bool>(false),),
ChangeNotifierProvider<ValueNotifier<int>>(create: (_) => ValueNotifier<int>(0),)
],
child: MaterialApp(
debugShowCheckedModeBanner: false,
title: 'Online Local Grocery',
locale: DevicePreview.of(context).locale,
builder: DevicePreview.appBuilder,
theme: ThemeData(
primaryColor: Colors.white,
fontFamily: 'Montserrat',
appBarTheme: AppBarTheme(elevation: 0.0), //This is important
),
initialRoute: AuthWidget.id,
navigatorKey: navigatorKey,
onGenerateRoute: RouteGenerator.generateRoute,
//onGenerateInitialRoutes: InitialRouteGenerator.generateRoute(),
)
,
);
}
}
路线生成器.dart
class RouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
final args = settings.arguments;
switch (settings.name) {
case AuthWidget.id:
return MaterialPageRoute(builder: (_) => AuthWidget());
case SignUpSelectionScreen.id:
return MaterialPageRoute(builder: (_) => SignUpSelectionScreen());
case SignupForm.id:
return MaterialPageRoute(builder: (_) => SignupForm());
case LoginView.id:
return MaterialPageRoute(builder: (_) => LoginView());
case HomePage.id:
return MaterialPageRoute(builder: (_) => HomePage());
case MainPage.id:
if (args.runtimeType == MainCategory) {
return MaterialPageRoute(
builder: (_) => MainPage(
mainCategory: args,
));
}
return _errorRoute();
case ProductDetail.id:
if (args.runtimeType == SelectedProductArguments) {
return MaterialPageRoute(
builder: (_) => ProductDetail(
selectedProductArguments: args,
));
}
return _errorRoute();
case CheckOutScreen.id:
return MaterialPageRoute(builder: (_) => CheckOutScreen());
case Admin.id:
return MaterialPageRoute(builder: (_) => Admin());
case ScrapBoard.id:
return MaterialPageRoute(builder: (_) => ScrapBoard());
case ProductAdminView.id:
return MaterialPageRoute(builder: (_) => ProductAdminView());
case DeliveryAddressView.id:
return MaterialPageRoute(builder: (_) => DeliveryAddressView());
case PaymentView.id:
return MaterialPageRoute(builder: (_) => PaymentView());
case OrderProcessingView.id:
return MaterialPageRoute(builder: (_) => OrderProcessingView());
case MyOrdersView.id:
return MaterialPageRoute(builder: (_) => MyOrdersView());
case MyOrderDetails.id:
if (args.runtimeType == Order) {
return MaterialPageRoute(builder: (_) => MyOrderDetails(
order: args,
)
);
}
return _errorRoute();
default:
// If there is no such named route in the switch statement, e.g. /third
return _errorRoute();
}
}
static Route<dynamic> _errorRoute() {
return MaterialPageRoute(builder: (_) {
return Scaffold(
appBar: AppBar(
title: Text('Error'),
),
body: Center(
child: Text('ERROR'),
),
);
});
}
}
class InitialRouteGenerator {
static Route<dynamic> generateRoute(RouteSettings settings) {
bool _firstTimeAppUsed;
final localStorage = new SharedPreferenceService();
localStorage.isFirstTimeAppUsed().then((bool value) {
if (value == true) {
_firstTimeAppUsed = true;
}
});
if (_firstTimeAppUsed) {
return MaterialPageRoute(builder: (_) => SignUpSelectionScreen());
}
return MaterialPageRoute(builder: (_) => HomePage());
}
}
AuthWidget.dart
class AuthWidget extends StatelessWidget {
static const id = "auth_widget";
@override
Widget build(BuildContext context) {
print("Auth Widget...");
final authService =
Provider.of<FirebaseAuthService>(context, listen: false);
final userModel = Provider.of<UserModel>(context, listen: false);
final signInHelperService = Provider.of<SignInHelperService>(context, listen: false);
return StreamBuilder(
stream: authService.onAuthStateChanged,
builder: (context, snapshot) {
if (snapshot.connectionState == ConnectionState.active) {
print ("INSIDE AUTH WIDGET");
final user = snapshot.data;
if (user != null) {
print("${user.uid} ${user.userName} ${user.photoUrl}");
userModel.user = user;
return StreamBuilder(
stream: FirebaseFirestore.instance
.collection('users')
.doc(user.uid)
.get().asStream(),
builder: (context, userSnapshot) {
if (userSnapshot.hasData && snapshot.connectionState == ConnectionState.active) {
final userDocument = userSnapshot.data;
if (userDocument != null) {
print("------ Data Found -------");
AppUser user = AppUser.fromMap(userDocument);
//bool signUpComplete = userDocument["signUpComplete"];
bool signUpComplete = user.signUpComplete;
if (signUpComplete == null) signUpComplete = false;
if (!signUpComplete) {
print("userModel.user UID ${userModel.user.uid}");
return SignupForm();
} else {
AppUser user2 = AppUser.fromMap(userDocument);
userModel.user = user2;
print('User Level ..... ${userModel.user.userLevel}');
signInHelperService.getAndUpdateDeviceToken(user2);
return HomePage(); //MainPage();
}
}
}
return emptyScaffoldWithProgress();
});
}
return SignUpSelectionScreen();
}
return emptyScaffoldWithProgress();
});
}
Scaffold emptyScaffoldWithProgress() {
return Scaffold(
body: Center(
child: SizedBox(
height: 90,
width: 90,
child: CircularProgressIndicator(
strokeWidth: 5.0,
valueColor: AlwaysStoppedAnimation<Color>(Colors.redAccent)),
),
),
);
}
}
扑动医生-v
[√] Flutter (Channel stable, 1.22.4, on Microsoft Windows [Version 10.0.19041.630], locale en-US)
• Flutter version 1.22.4 at C:\src\flutter
• Framework revision 1aafb3a8b9 (3 weeks ago), 2020-11-13 09:59:28 -0800
• Engine revision 2c956a31c0
• Dart version 2.10.4
[√] Android toolchain - develop for Android devices (Android SDK version 29.0.3)
• Android SDK at C:\Users\Jamal\AppData\Local\Android\sdk
• Platform android-29, build-tools 29.0.3
• Java binary at: C:\Android\Android Studio\jre\bin\java
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)
• All Android licenses accepted.
[√] Android Studio (version 4.0)
• Android Studio at C:\Android\Android Studio
• Flutter plugin version 47.1.2
• Dart plugin version 193.7361
• Java version OpenJDK Runtime Environment (build 1.8.0_242-release-1644-b01)
[√] VS Code (version 1.51.1)
• VS Code at C:\Users\Jamal\AppData\Local\Programs\Microsoft VS Code
• Flutter extension version 3.17.0
[√] Connected device (1 available)
• Android SDK built for x86 (mobile) • emulator-5554 • android-x86 • Android 10 (API 29) (emulator)
• No issues found!
