Flutter Firebase Authentication

Flutter Firebase Authentication is a Flutter development framework feature that allows developers to add user authentication functionalities to their Flutter applications by integrating Firebase Authentication. Firebase Authentication is a simple and secure authentication service provided by Google Firebase. With Flutter Firebase Authentication, app users can register and sign in to access authenticated features and services.

Getting Started

To use Flutter Firebase Authentication, developers must first integrate Firebase with their Flutter application. This can be done by adding the following dependency to the Flutter project in the pubspec.yaml file: ```yaml firebase_core: ^0.7.0 firebase_auth: ^0.20.1} After the successful integration of Firebase, developers can add Firebase Authentication functionalities to their Flutter application by following the below steps:

Signing Up New Users

In Flutter Firebase Authentication, signing up new users is achieved by using the signInWithCredential() method. The method takes the user's credentials as the parameter during sign-up. An example of signing up new users is illustrated in the code snippet below:

try {
  UserCredential result = await FirebaseAuth.instance.createUserWithEmailAndPassword(
    email: email,
    password: password
  );
  User newUser = result.user;
} on FirebaseAuthException catch (e){
  if (e.code == 'weak-password') {
    print('The password provided is too weak.');
  } else if (e.code == 'email-already-in-use') {
    print('The account already exists for that email.');
  }
} catch (e) {
  print(e);
}

Signing In Users

Signing in users is done using the signInWithEmailAndPassword() method. The method takes the already registered user's email and password as the parameter. An example of how to sign-in users is illustrated in the code snippet below:

try {
  UserCredential result = await FirebaseAuth.instance.signInWithEmailAndPassword(
      email: email,
      password: password
  );
  User user = result.user;
} on FirebaseAuthException catch (e) {
  if (e.code == 'user-not-found') {
    print('No user found for that email.');
  } else if (e.code == 'wrong-password') {
    print('Wrong password provided for that user.');
  }
} catch (e) {
  print(e);
}

Signing Out Users

To sign-out a user from the Flutter application, the currentUser() method is called to retrieve the current user's instance from the FirebaseAuth service. The user instance retrieved is then used to call the signOut() method, which signs out the user from the application. Below is an example of how to sign-out a user:

await FirebaseAuth.instance.signOut();}

Conclusion

Flutter Firebase Authentication is an excellent framework feature to add user authentication functionalities to your Flutter application with ease. By following the above steps, developers can easily enable their users to sign up, sign in, and sign out of the application using Firebase Authentication.