Argthtjtr

I am just starting to work with FirebaseUI email/password authentication.

My app is very simple, so far it's made of 1 activity that holds 3 fragments using a TabLayout and looks like this:

public class MainActivity extends AppCompatActivity {



    @Override

    protected void onCreate(Bundle savedInstanceState) {



        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);



        ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);

        TabsAdapter adapter = new TabsAdapter(this, getSupportFragmentManager());   

        viewPager.setAdapter(adapter);     

        TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);

        tabLayout.setupWithViewPager(viewPager);



        }

    }

On the Firebase assistant, it shows that I need to check if the user is signed in, in the onStart:

@Override

public void onStart() {

    super.onStart();

    // Check if user is signed in (non-null) and update UI accordingly.

    FirebaseUser currentUser = mAuth.getCurrentUser();

    updateUI(currentUser);

}

Then, the assistant shows how to sign up and sign in a user, but it doesn't show in which part of the activity it should go: onCreate? onStart?

*This is the signing up code:

mAuth.createUserWithEmailAndPassword(email, password)

        .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {

            @Override

            public void onComplete(@NonNull Task<AuthResult> task) {

                if (task.isSuccessful()) {

                    // Sign in success, update UI with the signed-in user's information

                    Log.d(TAG, "createUserWithEmail:success");

                    FirebaseUser user = mAuth.getCurrentUser();

                    updateUI(user);

                } else {

                    // If sign in fails, display a message to the user.

                    Log.w(TAG, "createUserWithEmail:failure", task.getException());

                    Toast.makeText(EmailPasswordActivity.this, "Authentication failed.",

                            Toast.LENGTH_SHORT).show();

                    updateUI(null);

                }



                // ...

            }

        });

*This is the sign-in code

mAuth.signInWithEmailAndPassword(email, password)

        .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {

            @Override

            public void onComplete(@NonNull Task<AuthResult> task) {

                if (task.isSuccessful()) {

                    // Sign in success, update UI with the signed-in user's information

                    Log.d(TAG, "signInWithEmail:success");

                    FirebaseUser user = mAuth.getCurrentUser();

                    updateUI(user);

                } else {

                    // If sign in fails, display a message to the user.

                    Log.w(TAG, "signInWithEmail:failure", task.getException());

                    Toast.makeText(EmailPasswordActivity.this, "Authentication failed.",

                            Toast.LENGTH_SHORT).show();

                    updateUI(null);

                }



                // ...

            }

        });

I am confused, assuming I currently have the working app, with the code provided above, what is the work flow now? Do I need to make this signup / signin code in the Mainactivity, and then, instead of the updateUI(null); pseudo-code provided by the Firebase assistant, I should make a new "main activity" with only the firebase auth code, and then use intents to send user to what's currently the main activity, which will be renamed to something like "SignedInActivity", or everything is done in the same current activity?

**Edit: To clarify what I mean:
I currently have MainActivity.
Do I need to:

1) change this current MainActivity to SignedInActivity, and then replace the current MainActivity with the Firebase activity, and then send intent to SignedInActivity upon successfull login

Or

2) Modify current MainActivity with the Firebase code so that I still have the current MainActivity with extra code of the Firebase?

I am confused as well, so hopefully my post is understandable

You really should look up the Android Lifecycle. It is important to know when the callbacks(onCreate, onStart, onResume, etc...) are called and then you can decide on your own where to implement the code.

In your case I would make a LoginActivity where you also can register a new profile with "createUserWithEmailAndPassword()" and Login with an already created Account. If it is successfull you can start the MainActivity.

mAuth.signInWithEmailAndPassword(email, password)

    .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {

        @Override

        public void onComplete(@NonNull Task<AuthResult> task) {

            if (task.isSuccessful()) {

                // Sign in success, update UI with the signed-in user's information

               Log.d(TAG, "signInWithEmail:success");



               Intent intent = new Intent(this, MainActivity.class);

               startActivity(intent);



            } else {

                // If sign in fails, display a message to the user.

                Log.w(TAG, "signInWithEmail:failure", task.getException());

                Toast.makeText(EmailPasswordActivity.this, "Authentication failed.",

                        Toast.LENGTH_SHORT).show();

            }



            // ...

        }

    });

Then in the onCreate callback of the MainActivity you can double check if the user is logged in with:

@Override

public void onCreate() {

    super.onCreate();

    // Check if user is signed in (non-null) and update UI accordingly.

    FirebaseUser currentUser = mAuth.getCurrentUser();

    if(currentUser != null) {

        updateUI(currentUser);

    } else {

        //intent back to login screen

    }

}