谷歌登录 firebase

Question

I am new to firebase. I am trying to add google sign in to my app but i am facing an some problems with getting that done

signin.java

package com.example.app100;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Toast;

import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInClient;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.common.internal.SignInButtonImpl;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.firebase.auth.AuthCredential;
import com.google.firebase.auth.AuthResult;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.auth.FirebaseUser;
import com.google.firebase.auth.GoogleAuthProvider;

public class Signin extends AppCompatActivity {


    private static final int RC_SIGN_IN = 2 ;
    private static final String TAG ="sign in" ;
    private FirebaseAuth mAuth;
    GoogleSignInClient mGoogleSignInClient;
    FirebaseAuth.AuthStateListener mAuthListener;


    @Override
    protected void onStart() {
        super.onStart();
        mAuth.addAuthStateListener(mAuthListener);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_signin);
        SignInButton signInButton = findViewById(R.id.sign_in);
        mAuth = FirebaseAuth.getInstance();

        signInButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                signIn();
            }
        });

        mAuthListener = new FirebaseAuth.AuthStateListener() {
            @Override
            public void onAuthStateChanged(@NonNull FirebaseAuth firebaseAuth) {
                if(firebaseAuth.getCurrentUser() != null)
                    startActivity(new Intent(Signin.this , MainActivity.class));
            }
        };

        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();

        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);


    }


    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) {
            Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
            try {
                // Google Sign In was successful, authenticate with Firebase
                GoogleSignInAccount account = task.getResult(ApiException.class);
                firebaseAuthWithGoogle(account);
                startActivity(new Intent(Signin.this , MainActivity.class));
            } catch (ApiException e) {
                // Google Sign In failed, update UI appropriately
                Log.w(TAG, "Google sign in failed", e);
                // ...
            }
        }
    }

    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) {
                        if (task.isSuccessful()) {
                            // Sign in success, update UI with the signed-in user's information
                            Log.d(TAG, "signInWithCredential:success");
                            FirebaseUser user = mAuth.getCurrentUser();
                            //updateUI(user);
                        } else {
                            // If sign in fails, display a message to the user.
                            Log.w(TAG, "signInWithCredential:failure", task.getException());
                            //Snackbar.make(findViewById(R.id.main_layout), "Authentication Failed.", Snackbar.LENGTH_SHORT).show();
                            //updateUI(null);
                        }

                        // ...
                    }
                });
    }


}

ERRORS:

    --------- beginning of crash
E/AndroidRuntime: FATAL EXCEPTION: main
    Process: com.example.app100, PID: 15815
    java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=2, result=-1, data=Intent { (has extras) }} to activity {com.example.app100/com.example.app100.Signin}: java.lang.IllegalArgumentException: Must specify an idToken or an accessToken.
        at android.app.ActivityThread.deliverResults(ActivityThread.java:4461)
        at android.app.ActivityThread.handleSendResult(ActivityThread.java:4503)
        at android.app.servertransaction.ActivityResultItem.execute(ActivityResultItem.java:49)
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1839)
        at android.os.Handler.dispatchMessage(Handler.java:106)
        at android.os.Looper.loop(Looper.java:201)
        at android.app.ActivityThread.main(ActivityThread.java:6864)
        at java.lang.reflect.Method.invoke(Native Method)
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873)
     Caused by: java.lang.IllegalArgumentException: Must specify an idToken or an accessToken.
        at com.google.firebase.auth.GoogleAuthCredential.<init>(com.google.firebase:firebase-auth@@19.3.0:3)
        at com.google.firebase.auth.GoogleAuthProvider.getCredential(com.google.firebase:firebase-auth@@19.3.0:2)
        at com.example.app100.Signin.firebaseAuthWithGoogle(Signin.java:105)
        at com.example.app100.Signin.onActivityResult(Signin.java:92)
        at android.app.Activity.dispatchActivityResult(Activity.java:7598)
        at android.app.ActivityThread.deliverResults(ActivityThread.java:4454)
        at android.app.ActivityThread.handleSendResult(ActivityThread.java:4503) 
        at android.app.servertransaction.ActivityResultItem.execute(ActivityResultItem.java:49) 
        at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
        at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
        at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1839) 
        at android.os.Handler.dispatchMessage(Handler.java:106) 
        at android.os.Looper.loop(Looper.java:201) 
        at android.app.ActivityThread.main(ActivityThread.java:6864) 
        at java.lang.reflect.Method.invoke(Native Method) 
        at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:547) 
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:873) 
I/Process: Sending signal. PID: 15815 SIG: 9

I read other answers on stackoverflow and updated the SHA1 from Variant: debug Config: debug in firebase console.

Can someone guide me how to resolve these errors with google sign in
.

Answer 1

You need to add IdToken to authenticate

replace this

GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();

with

GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
        .requestIdToken(getString(R.string.default_web_client_id))
        .requestEmail()
        .build();

For further, here is the official docs of firebase google sign in: https://firebase.google.com/docs/auth/android/google-signin