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FirebaseAuth.getInstance() throwing exception java.lang.NoSuchMethodError

I'm implementing google sign-in using firebase, when I'm getting instance of firebaseauth class then its throws an exception,
java.lang.NoSuchMethodError
but my code is copied as it is from documentation(https://firebase.google.com/docs/auth/android/google-signin). Please help.
code:
public class LoginActivity extends AppCompatActivity {
private static final String TAG = "LoginActivity_Firebase";
private static final int RC_SIGN_IN = 9001;
private FirebaseAuth mAuth;
private GoogleSignInClient mGoogleSignInClient;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
mAuth = FirebaseAuth.getInstance(); //this line is shown as error
//finding button and setting click listener
findViewById(R.id.signInButton).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
signIn();
}
});
}
void setupGoogleSignIn(){
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
}
private void signIn() {
setupGoogleSignIn();
Intent signInIntent = mGoogleSignInClient.getSignInIntent(); //getting signIn intent from googleclient
startActivityForResult(signInIntent, RC_SIGN_IN);
}
#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) {
Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
try {
// Google Sign In was successful, authenticate with Firebase
GoogleSignInAccount account = task.getResult(ApiException.class);
Log.d(TAG, "firebaseAuthWithGoogle: " + account.getIdToken());
firebaseAuthWithGoogle(account.getIdToken());
} catch (ApiException e) {
// Google Sign In failed, update UI appropriately
Log.w(TAG, "Google sign in failed", e);
}
}
}
private void firebaseAuthWithGoogle(String idToken) {
Log.d(TAG, "firebaseAuthWithGoogle: called");
AuthCredential credential = GoogleAuthProvider.getCredential(idToken, null);
mAuth.signInWithCredential(credential)
.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, "signInWithCredential:success");
FirebaseUser user = mAuth.getCurrentUser();
} else {
// If sign in fails, display a message to the user.
Log.w(TAG, "signInWithCredential:failure", task.getException());
}
}
});
}
}
The complete Logcat
Process: com.recipeapp.marathi, PID: 13369
java.lang.NoSuchMethodError: No virtual method setTokenProvider(Lcom/google/firebase/internal/InternalTokenProvider;)V in class Lcom/google/firebase/FirebaseApp; or its super classes (declaration of 'com.google.firebase.FirebaseApp' appears in /data/app/com.recipeapp.marathi-3W2YRoeaSMJdnEELQ9KFbw==/base.apk)
at com.google.firebase.auth.FirebaseAuth.zza(Unknown Source:22)
at com.google.firebase.auth.FirebaseAuth.getInstance(Unknown Source:4)
at com.recipeapp.marathi.activities.LoginActivity.onCreate(LoginActivity.java:37)
at android.app.Activity.performCreate(Activity.java:7964)
at android.app.Activity.performCreate(Activity.java:7953)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1307)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3472)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3636)
at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:83)
at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:140)
at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:100)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2222)
at android.os.Handler.dispatchMessage(Handler.java:107)
at android.os.Looper.loop(Looper.java:228)
at android.app.ActivityThread.main(ActivityThread.java:7782)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:492)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:981)
dependencies:
//auth firebase
implementation platform('com.google.firebase:firebase-bom:26.7.0')
implementation "com.google.firebase:firebase-database:$firebase_google_version"
implementation "com.google.firebase:firebase-auth:$firebase_google_version"
implementation "com.google.android.gms:play-services-auth:$firebase_google_version"
implementation "com.google.firebase:firebase-ads:$firebase_google_version"
implementation 'com.firebaseui:firebase-ui-database:7.1.1'
pls help me fix this.

Multiple Auth Providers Android Firebase

I have LoginActivity with Email/password login, facebook, google authentication. It works separately but if I create account with google, I can't login with facebook.
Login activity code:
public class LoginActivity extends AppCompatActivity {
private Button mLogin,mRegister;
private int RC_SIGN_IN =0;
private EditText mEmail, mPassword;
public FirebaseAuth mAuth;
private FirebaseAuth.AuthStateListener firebaseAuthStateListener;
CallbackManager callbackManager;
private LoginButton loginButton;
private static final String EMAIL = "email";
private TextView facebookRegister;
private SignInButton googleSignIn;
GoogleSignInClient mGoogleSignInClient;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
Intent intent = new Intent(LoginActivity.this, LoginTest.class);
startActivity(intent);
//FACEBOOK
mAuth = FirebaseAuth.getInstance();
FacebookSdk.sdkInitialize(getApplicationContext());
AppEventsLogger.activateApp(getApplication());
callbackManager = CallbackManager.Factory.create();
// Configure sign-in to request the user's ID, email address, and basic
// profile. ID and basic profile are included in DEFAULT_SIGN_IN.
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
// Build a GoogleSignInClient with the options specified by gso.
mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
googleSignIn = findViewById(R.id.sign_in_button);
googleSignIn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.sign_in_button:
signIn();
break;
// ...
}
}
});
firebaseAuthStateListener= new FirebaseAuth.AuthStateListener() {
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth firebaseAuth) {
final FirebaseUser user = FirebaseAuth.getInstance().getCurrentUser();
if(user !=null){
Intent intent = new Intent(LoginActivity.this, MainActivity.class);
startActivity(intent);
finish();
return;
}
}
};
loginButton = findViewById(R.id.login_button);
loginButton.setReadPermissions(Arrays.asList(EMAIL));
mLogin = (Button) findViewById(R.id.login);
mEmail = (EditText) findViewById(R.id.email);
mPassword=(EditText) findViewById(R.id.password);
mRegister=(Button)findViewById(R.id.register);
// Callback registration
loginButton.registerCallback(callbackManager, new FacebookCallback<LoginResult>() {
#Override
public void onSuccess(LoginResult loginResult) {
// App code
handleFacebookToken(loginResult.getAccessToken());
//fill database
}
#Override
public void onCancel() {
// App code
}
#Override
public void onError(FacebookException exception) {
// App code
}
});
mLogin.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
logInEmailPassword();
}
});
mRegister.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(LoginActivity.this, RegistrationActivity.class);
startActivity(intent);
finish();
return;
}
});
}
#Override
protected void onStart() {
super.onStart();
GoogleSignInAccount account = GoogleSignIn.getLastSignedInAccount(this);
mAuth.addAuthStateListener(firebaseAuthStateListener);
}
#Override
protected void onStop() {
super.onStop();
mAuth.removeAuthStateListener(firebaseAuthStateListener);
}
private void logInEmailPassword() {
String email = mEmail.getText().toString();
String password = mPassword.getText().toString();
if(email.isEmpty()){
Toast.makeText(LoginActivity.this, "Wrong email", Toast.LENGTH_SHORT).show();
mEmail.setError("Enter email!");
};
if(password.isEmpty()){
mPassword.setError("Enter password!");
Toast.makeText(LoginActivity.this, "Wrong password", Toast.LENGTH_SHORT).show();
}
if(!email.isEmpty() && !password.isEmpty()){
AuthCredential credential = EmailAuthProvider.getCredential(email, password);
linkWithCredential(credential);
}
}
private void handleFacebookToken(AccessToken token) {
AuthCredential credential = FacebookAuthProvider.getCredential(token.getToken());
linkWithCredential(credential);
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
callbackManager.onActivityResult(requestCode, resultCode, data);
// Result returned from launching the Intent from GoogleSignInClient.getSignInIntent(...);
if (requestCode == RC_SIGN_IN) {
// The Task returned from this call is always completed, no need to attach
// a listener.
Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
handleSignInResult(task);
}
}
private void signIn() {
Intent signInIntent = mGoogleSignInClient.getSignInIntent();
startActivityForResult(signInIntent, RC_SIGN_IN);
}
private void handleSignInResult(Task<GoogleSignInAccount> completedTask) {
try {
GoogleSignInAccount account = completedTask.getResult(ApiException.class);
FirebaseGoogleAuth(account);
// Signed in successfully, show authenticated UI.
} catch (ApiException e) {
// The ApiException status code indicates the detailed failure reason.
// Please refer to the GoogleSignInStatusCodes class reference for more information.
Log.w("myLog", "signInResult:failed code=" + e.getStatusCode());;
}
}
private void FirebaseGoogleAuth(GoogleSignInAccount account) {
AuthCredential authCredential = GoogleAuthProvider.getCredential(account.getIdToken(),null);
linkWithCredential(authCredential);
}
private void linkWithCredential(AuthCredential credential){
mAuth = FirebaseAuth.getInstance()
//mAuth.getCurrentUser().linkWithCredential(credential)
mAuth.signInWithCredential(credential)
.addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
#Override
public void onComplete(#NonNull Task<AuthResult> task) {
if (task.isSuccessful()) {
Log.d("myLog", "linkWithCredential:success");
FirebaseUser user = task.getResult().getUser();
updateUI(user);
} else {
Log.w("myLog", "linkWithCredential:failure", task.getException());
Toast.makeText(LoginActivity.this, "Authentication failed.",
Toast.LENGTH_SHORT).show();
LoginManager.getInstance().logOut();
updateUI(null);
}
// ...
}
});
}
}
I've followed https://firebase.google.com/docs/auth/android/account-linking?authuser=0 tutorial but I stuck at linkWithCredential.
Can you help me fix that issue? Thanks

The problem if that user exists in Firebase Authentication already and is assigned to GoogleAuth i cant login with Facebook.
It works vice versa, if facebook user exists in firebase and i login with google it overrides that user.
Register ---- logout ---- login
Google --->>>>>>>>>>>>>>>>Facebook >>>>dont work
Facebook--->>>>>>>>>>>>>>>Google >>>>> works

android - Firebase Google Authentication user not logging out

My MainActivity contains a GoogleSignIn button which pops up a menu with all the google accounts on the device. All works fine. The user is able to log in successfully, and directed to a new Activity.
Now, the new Activity (Main2Activity) contains a log-out button, which redirects the user to MainActivity again. But when I click on GoogleSignIn button again, the same user is again logged in. I want the account selection menu to pop up once again. What if the user wants to signin with other account?
Here's the signout code I'm using in Main2Activity:
HomeActivity/Main2Activity
findViewById(R.id.logoutButton).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v)
{
firebaseAuth.signOut();
startActivity(new Intent(getApplicationContext(), LoginActivity.class));
finish();
}
});
}
LoginActivity/MainActivity
package com.dell.nfclib;
public class LoginActivity extends Activity
{
private static final int RC_SIGN_IN = 101;
GoogleSignInClient mGoogleSignInClient;
private FirebaseAuth mAuth;
SignInButton signInButton;
#Override
protected void onStart()
{
super.onStart();
}
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
// Configure Google Sign In
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
// Build a GoogleSignInClient with the options specified by gso.
mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
// Initialize Firebase Auth
mAuth = FirebaseAuth.getInstance();
signInButton = (SignInButton) findViewById(R.id.googleSignInButton);
signInButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
signIn();
}
});
}
private void signIn()
{
Intent signInIntent = mGoogleSignInClient.getSignInIntent();
startActivityForResult(signInIntent, RC_SIGN_IN);
}
#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()) {
GoogleSignInAccount account = result.getSignInAccount();
firebaseAuthWithGoogle(account);
}
}
}
private void firebaseAuthWithGoogle(GoogleSignInAccount acct)
{
AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
mAuth.signInWithCredential(credential)
.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
// Get user details from the 'user' object..
startActivity(new Intent(getApplicationContext(), HomeActivity.class));
finish();
}
else
{
// If sign in fails, display a message to the user.
Toast.makeText(getApplicationContext(), "Error", Toast.LENGTH_LONG).show();
}
// ...
}
});
}
}

But when I click on GoogleSignIn button again, the same user is again logged in.
This is happening because you haven't signed out completely.
I want the account selection menu to pop up once again.
To solve this, you need to sign-out from both, Firebase and Google accounts. A method like the following can help you solve your problem:
private void signOut() {
FirebaseFirestore.getInstance().signOut(); //Sign-out Firebase
if (googleApiClient.isConnected()) {
Auth.GoogleSignInApi.signOut(googleApiClient); //Sign-out Google
}
}

Android FireBase - Connect to Game Service Leaderboard

I have made a login activity using firebase to connect with google. The user can login without problems Now I want to show a leaderboard on another activity however, when I check if the user is logged in and I try to show the leaderboard I get the error:
E/UncaughtException: java.lang.IllegalStateException: GoogleApiClient
must be connected.
How can I connect GoogleApiClient using firebase? I have tried using mGoogleApiClient.connect(GoogleApiClient.SIGN_IN_MODE_OPTIONAL); but this also does not work.
here my code:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_achievements);
// Configure Google Sign In
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.enableAutoManage(this, new GoogleApiClient.OnConnectionFailedListener() {
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
// connection failed, should be handled
}
})
.addApi(Auth.GOOGLE_SIGN_IN_API, gso)
.build();
mAuth = FirebaseAuth.getInstance();
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());
////// is crashing googleapiclient not connected
startActivityForResult(Games.Leaderboards.getLeaderboardIntent(mGoogleApiClient,
getString(R.string.leaderboard_la_classifica)), REQUEST_LEADERBOARD);
} else {
// User is signed out
}
// ...
}
};
}

See https://firebase.google.com/docs/auth/android/google-signin for more details.
When building the client, you need to use GoogleSignInOptions.DEFAULT_GAMES_SIGN_IN.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.fragment_firebase_games_signin);
String webclientId = getString(R.string.web_client_id);
GoogleSignInOptions options =
new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_GAMES_SIGN_IN)
.requestServerAuthCode(webclientId)
.requestEmail()
.requestIdToken()
.build();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addApi(Games.API).addScope(Games.SCOPE_GAMES)
.addApi(Auth.GOOGLE_SIGN_IN_API, options)
.addConnectionCallbacks(this)
.build();
}
Then to start the explicit sign-in start the signIn Intent:
private void signIn() {
Intent signInIntent =
Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
startActivityForResult(signInIntent, RC_SIGN_IN);
}
You should also use an automanaged client, or simply call mGoogleApiClient.connect(GoogleApiClient.SIGN_IN_MODE_OPTIONAL); in onStart() and disconnect in onStop().
In onActivityResult, handle the result of the explicit sign-in intent:
#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()) {
// Google Sign In was successful, authenticate with Firebase
GoogleSignInAccount acct = result.getSignInAccount();
completeFirebaseAuth(acct);
// At this point, the Games API can be called.
} else {
// Google Sign In failed, update UI appropriately
// ...
}
}
}
Completing the Firebase authentication:
private void completeFirebaseAuth(GoogleSignInAccount acct) {
AuthCredential credential = GoogleAuthProvider.getCredential(acct.getIdToken(), null);
FirebaseAuth mAuth = FirebaseAuth.getInstance();
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());
}
// ...
}
});
}
The other situation you need to handle is the silent sign-in, which happens when resuming an app:
#Override
public void onConnected(#Nullable Bundle bundle) {
// Handle the silent sign-in case.
if (mGoogleApiClient.hasConnectedApi(Games.API)) {
Auth.GoogleSignInApi.silentSignIn(mGoogleApiClient).setResultCallback(
new ResultCallback<GoogleSignInResult>() {
#Override
public void onResult(
#NonNull GoogleSignInResult googleSignInResult) {
if (googleSignInResult.isSuccess()) {
completePlayGamesAuth(
googleSignInResult.getSignInAccount());
} else {
Log.e(TAG, "Error with silentSignIn: " +
googleSignInResult.getStatus());
}
}
}
);
}
}

Android application takes too much time to start?

I'm finished with android app. Used firebase, admob. Has 31 activities. But when user installs the app for first time, the launch time is approximately 18 seconds which is too high. After first time launching, signup activity is there. But if we relaunch the app then it launches in 2 seconds. Why there is very high launch time? How can I reduce it? Below is my Sign up activity code. Using android studio 2.2
public class MainActivity extends AppCompatActivity {
private AdView mAdView;
private SignInButton mGoogleBtn;
private static final int RC_SIGN_IN=1;
private GoogleApiClient mGoogleApiClient;
private FirebaseAuth mAuth;
private static final String TAG="MAIN_ACTIVITY";
private FirebaseAuth.AuthStateListener mAuthListener;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mAuth=FirebaseAuth.getInstance();
mAuthListener=new FirebaseAuth.AuthStateListener() {
#Override
public void onAuthStateChanged(#NonNull FirebaseAuth firebaseAuth) {
if(firebaseAuth.getCurrentUser()!=null){
startActivity(new Intent(MainActivity.this,Home.class));
}
}
};
mGoogleBtn=(SignInButton)findViewById(R.id.view);
// Configure Google Sign In
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestIdToken(getString(R.string.default_web_client_id))
.requestEmail()
.build();
mGoogleApiClient=new GoogleApiClient.Builder(getApplicationContext())
.enableAutoManage(this, new GoogleApiClient.OnConnectionFailedListener() {
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
Toast.makeText(MainActivity.this,"Login via Google Failed! Press Skip",Toast.LENGTH_LONG).show();
}
})
.addApi(Auth.GOOGLE_SIGN_IN_API,gso)
.build();
mGoogleBtn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
signIn();
}
});
}
#Override
protected void onStart() {
super.onStart();
mAuth.addAuthStateListener(mAuthListener);
}
#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()) {
// Google Sign In was successful, authenticate with Firebase
GoogleSignInAccount account = result.getSignInAccount();
firebaseAuthWithGoogle(account);
} else {
// Google Sign In failed, update UI appropriately
// ...
}
}
}
private void firebaseAuthWithGoogle(GoogleSignInAccount account) {
Log.d(TAG, "firebaseAuthWithGoogle:" + account.getId());
AuthCredential credential = GoogleAuthProvider.getCredential(account.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. Press Skip.",
Toast.LENGTH_SHORT).show();
}
else {
Toast.makeText(MainActivity.this,"Login Successful! Welcome to Unipune Buddy!",Toast.LENGTH_LONG).show();
}
// ...
}
});
}
private void signIn() {
Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
startActivityForResult(signInIntent, RC_SIGN_IN);
}
public void mainscreen(View view){
Intent intent0=new Intent(this,Home.class);
Toast.makeText(MainActivity.this,"Signed in Successfully!",Toast.LENGTH_LONG).show();
startActivity(intent0);
}
}

I too had this issue, what i had done was disabling instant run in the project settings, and rebuilding the project, You can also use Cold start for engaging the user for the first time.