Авто логин в приложении android

Нужно сделать авто логин в приложении. Создано оно на Android Studio и авторизация на Firebase.

Вот код MainActivity:

public class MainActivity extends AppCompatActivity implements View.OnClickListener {
    private FirebaseAuth mAuth;
    private FirebaseAuth.AuthStateListener mAuthListener;
    private EditText et_email;
    private EditText et_password;
    private AdView mAdView;
    private TextView tname;
    private TextView temail;
    private static final String TAG = "MainActivity";
    //GoogleApiClient mGoogleSignInClient;
    //private static final String TAG = "SignInActivity";
    //private static final int RC_SIGN_IN = 9001;
    //private TextView mDetailTextView;
    //private TextView mStatusTextView;
    //private GoogleSignInOptions gso;
    //private GoogleSignInClient mGoogleSignInClient;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mAuth = FirebaseAuth.getInstance();
        super.onStart();

        // Check if user is signed in (non-null) and update UI accordingly.
        FirebaseUser currentUser = mAuth.getCurrentUser();

        mAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
                if (user != null) {
                    String name = user.getDisplayName();
                    String email = user.getEmail();
                    boolean emailVerified = user.isEmailVerified();
                    // The user's ID, unique to the Firebase project. Do NOT use this value to
                    // authenticate with your backend server, if you have one. Use
                    // FirebaseUser.getIdToken() instead.
                    String uid = user.getUid();
                } else {
                }
            }
        };

        et_email = (EditText) findViewById(R.id.et_email);
        et_password = (EditText) findViewById(R.id.et_password);
        tname = (TextView) findViewById(R.id.tname);
        temail = (TextView) findViewById(R.id.temail);
        findViewById(R.id.BVoiti).setOnClickListener(this);
        findViewById(R.id.change_email).setOnClickListener(this);
        findViewById(R.id.change_password).setOnClickListener(this);
        findViewById(R.id.btn_vk).setOnClickListener(this);
        findViewById(R.id.BReg).setOnClickListener(this);
    }

    @Override
    public void onClick(View view) {
        if (view.getId() == R.id.change_password) {
            changePasswoord();
        }else if(view.getId() == R.id.BVoiti){
            signing(et_email.getText().toString(),et_password.getText().toString());
            et_password.getText().clear();
            et_email.getText().clear();
        }else if (view.getId() == R.id.BReg){
            Intent intent1 = new Intent(MainActivity.this, RegActivity.class);
            startActivity(intent1);
        }

    }

    public void changePasswoord(){
        Intent intent = new Intent(MainActivity.this, ChangePassword.class);
        startActivity(intent);
    }

    public void signing(String email, String password){
        mAuth.signInWithEmailAndPassword(email,password).addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
            @Override
            public void onComplete(@NonNull Task<AuthResult> task) {
                if(task.isSuccessful()) {
                    if(mAuth.getCurrentUser().isEmailVerified()){
                        Toast.makeText(MainActivity.this, "Успешный вход",Toast.LENGTH_LONG).show();
                        Intent intent = new Intent(MainActivity.this,MainScreenActivity.class);
                        startActivity(intent);
                    }else{
                        Toast.makeText(MainActivity.this, "Верифицируйте ваш аккаунт",Toast.LENGTH_LONG).show();
                    }
                }else{
                    Toast.makeText(MainActivity.this, "Авторизация провалена", Toast.LENGTH_SHORT).show();
                }
            }
        });
    }



}

Если это не тот код который нужен для решения задачи пишите. Я новичёк в Android Разработке)