In Firebase Flutter how do I access details of the logged in user using my custom class

Issue

The code for the model class is as shown below:

class UserAuthModel {

  String? uid;
  String? email;
  String? displayName;
  String? profilePic;

  UserAuthModel(this.uid, this.email, this.displayName, this.profilePic);

  UserAuthModel.fromFirebaseUser({User? user}) {
    this.uid = user!.uid;
    this.email = user.email;
    this.displayName = user.displayName;
    this.profilePic = user.photoURL;
  }
}

The code for the service class is shown below:

class AuthService {
  final FirebaseAuth authInstance = FirebaseAuth.instance;
  final FirebaseFirestore firestoreInstance = FirebaseFirestore.instance;

  Stream<UserAuthModel?> get currentUser => authInstance.authStateChanges().map(
        (User? firebaseUser) => (firebaseUser != null) ? UserAuthModel.fromFirebaseUser(user: firebaseUser) : null,
      );
}

The provider is defined as shown below:

return MultiProvider(
      providers: [
        Provider<AuthService>(
          create: (_) => AuthService(),
        ),
      ],

This is how I’m trying to consume the provider within the code:

    final authService = Provider.of<AuthService>(context);
    final loggedInUser = authService.currentUser;

But when I try to access the user details using the currentUser as shown below, I’m unable to do so, not sure why?

   print(loggedInUser.uid);
   print(loggedInUser.email);
   print(loggedInUser.displayName);
   print(loggedInUser.profilePic);

How can I access these details?

I don’t see either the uid, email, displayName or profilePic to select as shown in the pic below:

Solution

The properties you are looking for are defined on UserAuthModel. But your loggedInUser is declared as this as far as I can see:

Stream<UserAuthModel?> get currentUser

So the properties you can read from loggedInUser are properties of Stream and not of UserAuthModel.

Reading the user model once

To get the properties of the actual UserAuthModel, you can use the methods of the Stream. For example you can await the first UserAuthModel with:

var user = await loggedInUser.first
print(user.uid);

Listening/observing the user model

You can also listen for changes to the logged in user, so that you don’t just get their initial state, but also any changes with:

loggedInUser.listen((user) {
  print(user.uid);
}

Showing the user model in your UI

And if you want to use the user in your UI, you’ll typically wrap it in a StreamBuilder, which then handles the asynchronous behavior of the stream for you and gives you a UserAuthModel to work with.

I highly recommend reading the Flutter documentation on asynchronous programming and on StreamBuilder to learn more about these concepts, as they’re fundamental to working with cloud-hosted data in Flutter.

Answered By – Frank van Puffelen

This Answer collected from stackoverflow, is licensed under cc by-sa 2.5 , cc by-sa 3.0 and cc by-sa 4.0

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