Firebase Facebook authentication showing weird activity

Question

We are implementing Firebase Facebook authentication for one of our projects. We have followed the steps mentioned in the documentation as well.

Here is the oAuth URL:

https://<APP_NAME>.firebaseapp.com/__/auth/handler

I've added the rest of the credentials as well (i.e the APP_ID & APP_SECRET), moreover the app is in development stage and I've added the key hash as well to the Facebook portal and Firebase portal.

The Login initial flow works well, but when the user confirm the permission to grant access, the callback register doesn't respond at all, neither with negative nor positive acknowledgement.

Here's our piece of code:

     private static final String TAG = "FacebookLogin";

    private CallbackManager mCallbackManager;

    private FirebaseAuth mAuth;
    private FirebaseAuth.AuthStateListener mAuthListener;

 mAuth = FirebaseAuth.getInstance();
        mAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                FirebaseUser user = firebaseAuth.getCurrentUser();
                if (user != null) {
                    // User is signed in
                    Log.d(TAG, "onAuthStateChanged:signed_in:" + user.getUid());
                } else {
                    // User is signed out
                    Log.d(TAG, "onAuthStateChanged:signed_out");
                }
                // ...
            }
        };

        // Initialize Facebook Login button
        mCallbackManager = CallbackManager.Factory.create();
        LoginButton loginButton = (LoginButton) findViewById(R.id.button_facebook_login);
        loginButton.setReadPermissions("email", "public_profile");
        loginButton.registerCallback(mCallbackManager, new FacebookCallback<LoginResult>() {
            @Override
            public void onSuccess(LoginResult loginResult) {
                Log.d(TAG, "facebook:onSuccess:" + loginResult);
                handleFacebookAccessToken(loginResult.getAccessToken());
            }

            @Override
            public void onCancel() {
                Log.d(TAG, "facebook:onCancel");
                // ...
            }

            @Override
            public void onError(FacebookException error) {
                Log.d(TAG, "facebook:onError"+ error);
                // ...
            }
        });

@Override
    public void onStart() {
        super.onStart();
        mAuth.addAuthStateListener(mAuthListener);
    }

    @Override
    public void onStop() {
        super.onStop();
        if (mAuthListener != null) {
            mAuth.removeAuthStateListener(mAuthListener);
        }
    }

    private void handleFacebookAccessToken(AccessToken token) {
        Log.d(TAG, "handleFacebookAccessToken:" + token);

        AuthCredential credential = FacebookAuthProvider.getCredential(token.getToken());
        mAuth.signInWithCredential(credential)
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        Log.d(TAG, "signInWithCredential:onComplete:" + task.isSuccessful());

                        // If sign in fails, display a message to the user. If sign in succeeds
                        // the auth state listener will be notified and logic to handle the
                        // signed in user can be handled in the listener.
                        if (!task.isSuccessful()) {
                            Log.w(TAG, "signInWithCredential", task.getException());
                            Toast.makeText(FacebookLoginActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        }

                        // ...
                    }
                });
    }

Please let us know if we missed anything. I'm assuming there's something wrong about the callback URL, thus a bit more information on the same would be helpful as Firebase documentation doesn't clearly state about how to build up that URL. Thanks in advance.

Answer 1

Did you add

mCallbackManager.onActivityResult(requestCode, resultCode, data);

in your onActivityResult block?

Edit

Referring to the sample from Firebase https://github.com/firebase/quickstart-android/blob/master/auth/app/src/minSdkJellybean/java/com/google/firebase/quickstart/auth/FacebookLoginActivity.java,

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    mCallbackManager.onActivityResult(requestCode, resultCode, data);
}

If this is not added, there would be no callback.