How convert FirebaseUser to string in flutter?

Question

Here is my code of a stateful class:

String id = FirebaseAuth.instance.currentUser().toString();

my function :

readLocal() async {
  prefs = await SharedPreferences.getInstance();
  id = prefs.getString('id') ?? '';
  if (id.hashCode <= peerId.hashCode) {
    groupChatId = '$id-$peerId';
  } else {
    groupChatId = '$peerId-$id';
  }
  setState(() {});
}

It works fine in String id.

I want the ID to be the same as the current user UID.

Frank van Puffelen · Answer 1 · 2019-03-27T01:43:32.133

1

Calling FirebaseAuth.instance.currentUser() return a FirebaseUser, which is an object with all user data. If you only want the UID of the user:

FirebaseUser user = await FirebaseAuth.instance.currentUser();
String uid = user.uid;

Update: I just ran this and it prints the UID for me:

void _getUser() async {
  FirebaseUser user = await FirebaseAuth.instance.currentUser();
  print(user.uid);
}

Which printed:

flutter: P07IXLCrwEahYlDhzO1Iv0SKDat2

Things to notice:

In order to be able to use await in the code, the method must be marked as async.

edited Mar 27 '19 at 01:43

answered Mar 25 '19 at 14:25

Frank van Puffelen

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Error is : The getter 'uid' isn't defined for the class 'Future'.dart(undefined_getter) – Ashwani Kumar Mar 25 '19 at 14:42
Got it. `currentUser` is asynchronous, so you'll need to await the result. I updated my answer. – Frank van Puffelen Mar 25 '19 at 14:54
Again error : A value of type 'Future' can't be assigned to a variable of type 'FirebaseUser'.dart(invalid_assignment) – Ashwani Kumar Mar 25 '19 at 15:51
Are you sure you added the `await` keyword? That should unwrap the `Future` into `FirebaseUser`. – Frank van Puffelen Mar 25 '19 at 17:03
Yes, here is my code FirebaseUser user = await FirebaseAuth.instance.currentUser(); String uid = user.uid; – Ashwani Kumar Mar 25 '19 at 17:07
Hmmm.... as far as I know that should unwrap the `Future`. https://stackoverflow.com/questions/46579358/getting-values-from-future-instances – Frank van Puffelen Mar 25 '19 at 19:03

How convert FirebaseUser to string in flutter?

1 Answers1