Implementing Syde An online Forum in Flutter (Update : Authenticate With Google)

in #utopian-io2 years ago



New Features

  • Authenticate User

    A platform such as this should be able to identify it's users. To achieve this, I implemented Google sign in.



Implementing the authentication was a bit straight forward with the flutter plug-in. To make things modular I used the bloc pattern to handle click events from the user and then respond to the click event by calling the sign in method on an abstract class I created. This abstract class handles everything concerning authentication.

  • The code block below is the auth bloc where we listen for data on the stream and react accordingly
class AuthBloc {
  final BaseAuth baseAuth;
  //stream controller to handle streams
  StreamController<ClickEvents> _controller = StreamController<ClickEvents>();

  AuthBloc(this.baseAuth) {
  //listen for data on the stream
    _inputStream().listen((event) {
      if (event is ClickEvents) {

//create a stream 
  Stream<ClickEvents> _inputStream() {

//create a sink- with a sink, data can be added unto the stream
  Sink<ClickEvents> get eventSink => _controller.sink;

//close the stream
  void dispose() {

abstract class ClickEvents {}

class LogInClick extends ClickEvents {}

//make a global instance of AuthBloc
final authBloc = AuthBloc(Auth());
  • The code snippet below shows abstract methods used for implementing the authentication. for full details check source code
abstract class BaseAuth {
  FirebaseAuth getFireBAseAuth();

  GoogleSignIn getGoogleLogin();

  Future<FacebookLoginResult> initFaceBookLogIn(
      FacebookLogin fbLogIn, List<String> permission);

  Future<GoogleSignInAuthentication> getGoogleSignInAuth();

  AuthCredential getAuthCredential(GoogleSignInAuthentication auth);

  Future<void> logUserOut(FirebaseAuth mAuth);

  Future<void> storeUser(FirebaseUser user);

  Future<FirebaseUser> signInWithCredentials(FirebaseAuth mAuth);
  • The code block stores user's details to fire-store if user details do not exist
Future<void> storeUser(FirebaseUser user) async {
    if (user != null) {
      // Check is already sign up
      final QuerySnapshot result = await Firestore.instance
          .where('id', isEqualTo: user.uid)
      final List<DocumentSnapshot> documents = result.documents;
      documents.forEach((val) {
        print("Data = ${}");
      if (documents.length == 0) {
        // Update data to server if new user
          'name': user.displayName,
          'photoUrl': user.photoUrl,
          'id': user.uid,

  • From the Login Screen, all we need is a line of code in the onTap function to begin authenticating a user
 onTap: () {

Technology Stack

  • Android Studio
  • Flutter: Flutter is google mobile framework for building beautiful cross-platform apps
  • FireBase: Firebase will provide us with online backend functionality such database, cloud functions, authentication, real-time functionalities etc
  • SQFlite : this is flutter version of SQLite. This will enable local storage on the phone
  • RxDart : RxDart is used for reactive programming
  • BLOc pattern is used as the architectural pattern for layering the app.


*Github *:


The screenshots above show the current state of the application. I will work towards implementing all the features as described above. More attention would be given to the layouts and presentation of the app, to improve the user's experience. Some of the updates to expect are:

  • Authenticate User
  • Persisting user post
  • Searching all posts
  • Providing different layouts
  • ToDo for users to track their daily progress
  • Push Notifications
  • Posts sharing
  • Users dashboard
  • Searching all users
  • Direct Messaging with Users
  • ChatGroup
  • Bookmarking post

Demo Video

Github -

How to contribute?

You can reach me by commenting on this post or send a message via [email protected] you want to make this application better, you can make a Pull Request. Github

  • The code contains too much dead code. You should remove all of the commented code before committing to the repo.
  • Your commits are too big, they should be broken down in smaller concerns.

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Thank you for your review, @helo! Keep up the good work!

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