Firebase Authentication Not working in signed APK

I'm using Firebase Google Sign in. It works perfectly via USB debugging. But when I generate signed APK, it stops working. Its not able to sign in. Using it on Android 5.1 & Android 6.0.1. Also, if the Google play services is not updated, it gives user prompt to update it because of which user may leave the app. How can I turn off the prompt and solve the error?

public class MainActivity extends AppCompatActivity implements  GoogleApiClient.OnConnectionFailedListener,
        View.OnClickListener {
private Button skip;
    private static final String TAG = "GoogleActivity";
    private static final int RC_SIGN_IN = 9001;
    private ProgressBar pb;
    // [START declare_auth]
    private FirebaseAuth mAuth;
    // [END declare_auth]

    // [START declare_auth_listener]
    private FirebaseAuth.AuthStateListener mAuthListener;
    // [END declare_auth_listener]

    private GoogleApiClient mGoogleApiClient;
    private TextView mStatusTextView;
    private TextView mDetailTextView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        pb=(ProgressBar)findViewById(R.id.signpro);
        pb.setVisibility(View.GONE);
        skip=(Button)findViewById(R.id.btnskip);
        skip.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                setContentView(R.layout.activity_home);
            }
        });
        // Views


        // Button listeners
        findViewById(R.id.sign_in_button).setOnClickListener(this);

        // [START config_signin]
        // Configure Google Sign In
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken(getString(R.string.default_web_client_id))
                .requestEmail()
                .build();
        // [END config_signin]

        mGoogleApiClient = new GoogleApiClient.Builder(this)
                .enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */)
                .addApi(Auth.GOOGLE_SIGN_IN_API, gso)
                .build();

        // [START initialize_auth]
        mAuth = FirebaseAuth.getInstance();
        // [END initialize_auth]

        // [START auth_state_listener]
        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());
                    setContentView(R.layout.activity_home);

                } else {
                    // User is signed out
                    Log.d(TAG, "onAuthStateChanged:signed_out");
                }
                // [START_EXCLUDE]

                // [END_EXCLUDE]
            }
        };
        // [END auth_state_listener]
    }

    // [START on_start_add_listener]
    @Override
    public void onStart() {
        super.onStart();
        mAuth.addAuthStateListener(mAuthListener);

    }
    // [END on_start_add_listener]

    // [START on_stop_remove_listener]
    @Override
    public void onStop() {
        super.onStop();
        if (mAuthListener != null) {
            mAuth.removeAuthStateListener(mAuthListener);
        }
    }
    // [END on_stop_remove_listener]

    // [START onactivityresult]
    @Override
    public void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        // Result returned from launching the Intent from GoogleSignInApi.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
            if (result.isSuccess()) {
                Toast.makeText(this, "Signing you in. Please Wait...", Toast.LENGTH_LONG).show();
                // Google Sign In was successful, authenticate with Firebase
                GoogleSignInAccount account = result.getSignInAccount();
                firebaseAuthWithGoogle(account);
                Toast.makeText(this, "Sign In Successful!", Toast.LENGTH_SHORT).show();
            } else {
                // Google Sign In failed, update UI appropriately
                // [START_EXCLUDE]

                Toast.makeText(this, "Google Sign In failed. Please Skip.", Toast.LENGTH_SHORT).show();
                pb.setVisibility(View.GONE);
                // [END_EXCLUDE]
            }
        }
    }
    // [END onactivityresult]

    // [START auth_with_google]
    private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
        Log.d(TAG, "firebaseAuthWithGoogle:" + acct.getId());
        // [START_EXCLUDE silent]

        // [END_EXCLUDE]

        AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
        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(MainActivity.this, "Authentication failed.",
                                    Toast.LENGTH_SHORT).show();
                        }
                        // [START_EXCLUDE]

                        // [END_EXCLUDE]
                    }
                });
    }
    // [END auth_with_google]

    // [START signin]
    private void signIn() {
        pb.setVisibility(View.VISIBLE);
        Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }
    // [END signin]



    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
        // An unresolvable error has occurred and Google APIs (including Sign-In) will not
        // be available.
        Log.d(TAG, "onConnectionFailed:" + connectionResult);
        Toast.makeText(this, "Google Play Services error.", Toast.LENGTH_SHORT).show();
    }

    @Override
    public void onClick(View v) {
        int i = v.getId();
        if (i == R.id.sign_in_button) {
            signIn();

        }
    }
}

Solution 1:

I had the same problem and I fixed the problem using these methods.

  1. Complete app signing on your Play store console using these instructions How to enable Google Play App Signing

  2. Go to your Firebase console Settings > General > Your apps > (Select your project) then add the SHA-1 from App signing certificate from your Play store. You can get SHA-1 by going to Release management -> App signing as show in this image.

enter image description here

Solution 2:

You are having fingerprint certificate in console, but its only for debugging purposes, for signed apk you need a production fingerprint certificate, and you can get one by

 c:\Program Files\Java\jdk1.6.25\bin>keytool -list -v -keystore c:\you_key_here.key