Firebase getCurrentUser is returning null in new android activity

Question

LoginActivity:

private FirebaseAuth firebaseAuth;
private FirebaseAuth.AuthStateListener mAuthListener;

@Override
protected void onCreate(Bundle savedInstan         


        

Answer 1

I had this same problem today. After going through your problem i again checked my code and i found my mistake.I was using signout() at the end of my 1st activity. After i removed that my code is working fine.

I am using the authStateListener given in the documentation.Set the listener in onCreate method. Funtion getCurrentUser() sets an background task to fetch current user so the listener is important.

onCreate()

mAuthListener = new FirebaseAuth.AuthStateListener() {
        @Override
        public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
            FirebaseUser user = firebaseAuth.getCurrentUser();
            if (user != null) {
                // User is signed in
                String UserId = mCurrentUser.getUid();
                mCurrentUser = user;
                Toast.makeText(ListActivity.this, "USER ID\n"+mUserId,Toast.LENGTH_SHORT).show();
            }
            else {
                Toast.makeText(ListActivity.this, "no id got", Toast.LENGTH_SHORT).show();
            }

        }
    };

In onStart or onResume method i am calling the getCurrentUser() method

onResume()

 mCurrentUser = mAuth.getCurrentUser();

in case of slow connection

mCurrentUser = user;

in onCreate() will take care of the problem. Personally i prefer to use getcurrentuser method in onStart() so that it gets some time to fetch the user if the app is running on a slow internet.

I hope this solves your problem. Thank You.