How do I sign out form Google Auth from Flutter? - firebase

Question

I am able to successfully - sign in a user using firebase using both Google and Facebook:
firebase_auth.dart, flutter_facebook_login.dart, google_sign_in.dart
I am able to sign out the firebase user using this function from a different widget:
Future<void>_signOut() async {
final FirebaseAuth _firebaseAuth = FirebaseAuth.instance;
return _firebaseAuth.signOut();
}
Now this is a catch-all for both types of logins, Google and Facebook, how can I determine if the user is a Google auth user in which case I can execute
final GoogleSignIn _googleSignIn = new GoogleSignIn();
...
_googleSignIn.signOut();
Additionally, if my sign out function is in a different widget and file how can I pass the GoogleSignIn object to be referenced to sign out?

Answer 1

There is bool Future type of method for GoogleSignIn and FacebookSignIn.
final facebookLogin = FacebookLogin();
final GoogleSignIn googleSignIn = new GoogleSignIn();
googleSignIn.isSignedIn().then((s) {});
facebookLogin.isLoggedIn.then((b) {});
you will get true or false using this you can use sign out method.
and for your 2nd problem of the solution is to create a global object for GoogleSignIn and facebook as well.
import 'dart:async';
import 'package:firebase_auth/firebase_auth.dart';
import 'package:google_sign_in/google_sign_in.dart';
import 'package:flutter_facebook_login/flutter_facebook_login.dart';
final facebookLogin = FacebookLogin();
final FirebaseAuth firebaseAuth = FirebaseAuth.instance;
final GoogleSignIn googleSignIn = new GoogleSignIn();
Future<FirebaseUser> signInWithGoogle() async {
// Attempt to get the currently authenticated user
GoogleSignInAccount currentUser = _googleSignIn.currentUser;
if (currentUser == null) {
// Attempt to sign in without user interaction
currentUser = await _googleSignIn.signInSilently();
}
if (currentUser == null) {
// Force the user to interactively sign in
currentUser = await _googleSignIn.signIn();
}
final GoogleSignInAuthentication googleAuth =
await currentUser.authentication;
// Authenticate with firebase
final FirebaseUser user = await firebaseAuth.signInWithGoogle(
idToken: googleAuth.idToken,
accessToken: googleAuth.accessToken,
);
assert(user != null);
assert(!user.isAnonymous);
return user;
}
Future<Null> signOutWithGoogle() async {
// Sign out with firebase
await firebaseAuth.signOut();
// Sign out with google
await googleSignIn.signOut();
}