尝试使用Google登录（与Firebase连接）时，身份验证失败

Question

我遵循了documentation，并尝试将代码用于Firebase的Google SignIn。 我已经在Firebase上正确添加了SHA-1指纹，并且还为Android和基于Google Cloud Platform的Web创建了两个OAuth 2.0客户端ID。但是，它仍然无法登录Google。当前有两个活动-1. MainActivity和2. Profile。以下是代码：

build.gradle

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'
allprojects {
    repositories {
        google()
        mavenCentral()
        maven {
            url "https://repository-achartengine.forge.cloudbees.com/snapshot/"
        }
    }
}
android {
    compileSdkVersion 30
    buildToolsVersion "30.0.2"

    defaultConfig {
        applicationId "com.example.grocery"
        minSdkVersion 16
        targetSdkVersion 30
        versionCode 1
        versionName "1.0"

        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
    }

    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    implementation fileTree(dir: "libs", include: ["*.jar"])
    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.1'
    implementation 'com.google.firebase:firebase-auth:16.0.5'
    implementation 'com.google.android.gms:play-services-auth:18.1.0'
    implementation 'com.google.android.material:material:1.2.1'
    testImplementation 'junit:junit:4.12'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <com.google.android.gms.common.SignInButton
        android:id="@+id/google_signIn"
        android:layout_width="match_parent"
        android:layout_height="100dp"
        android:layout_alignParentTop="true"
        android:layout_margin="10dp"
        android:padding="10dp"
        android:text="Text"
        android:textSize="18sp"
        tools:layout_editor_absoluteX="3dp"
        tools:layout_editor_absoluteY="286dp" />

</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.java

package com.example.grocery;

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

import android.content.Intent;
import android.os.Bundle;
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.api.ApiException;
import com.google.android.gms.tasks.OnCompleteListener;
import com.google.android.gms.tasks.Task;
import com.google.android.material.snackbar.Snackbar;
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 MainActivity extends AppCompatActivity {

    private GoogleSignInClient mGoogleSignInClient;
    private final static int RC_SIGN_IN = 123;
    private FirebaseAuth mAuth;

    @Override
    protected void onStart() {
        super.onStart();

        FirebaseUser user = mAuth.getCurrentUser();
        if(user != null) {
            startActivity(new Intent(getApplicationContext(), Profile.class));
        }
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        mAuth = FirebaseAuth.getInstance();

        createRequest();

        findViewById(R.id.google_signIn).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                signIn();
            }
        });
    }
    private void createRequest() {
        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() {
        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.getIdToken());
            } catch (ApiException e) {
                // Google Sign In failed, update UI appropriately
                Toast.makeText(this, "Sign In Failed!", Toast.LENGTH_SHORT).show();
            }
        }
    }

    private void firebaseAuthWithGoogle(String idToken) {
        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
                            FirebaseUser user = mAuth.getCurrentUser();
                            startActivity(new Intent(getApplicationContext(), Profile.class));
                        } else {
                            // If sign in fails, display a message to the user.
                            Toast.makeText(MainActivity.this, "Authentication Failed!", Toast.LENGTH_SHORT).show();
                        }

                        // ...
                    }
                });
    }
}

activity_profile.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".Profile">

    <Button
        android:id="@+id/logout"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Logout"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="TextView"
        tools:layout_editor_absoluteX="43dp"
        tools:layout_editor_absoluteY="74dp" />

    <TextView
        android:id="@+id/mail"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="TextView"
        tools:layout_editor_absoluteX="47dp"
        tools:layout_editor_absoluteY="131dp" />
</androidx.constraintlayout.widget.ConstraintLayout>

Profile.java

package com.example.grocery;

import androidx.appcompat.app.AppCompatActivity;

import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

import com.google.android.gms.auth.api.signin.GoogleSignIn;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.firebase.auth.FirebaseAuth;

public class Profile extends AppCompatActivity {

    TextView name, mail;
    Button logout;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_profile);

        logout = findViewById(R.id.logout);
        name = findViewById(R.id.name);
        mail = findViewById(R.id.mail);

        GoogleSignInAccount signInAccount = GoogleSignIn.getLastSignedInAccount(this);
        if (signInAccount != null) {
            name.setText(signInAccount.getDisplayName());
            mail.setText(signInAccount.getEmail());
        }

        logout.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                FirebaseAuth.getInstance().signOut();
                startActivity(new Intent(getApplicationContext(), MainActivity.class));
            }
        });
    }
}

该构建可以正确运行，但是无法在模拟器上通过Google进行身份验证。我已经在Firebase（以及电子邮件）上启用了Google登录。请帮忙，我也查看了StackOverflow和Google上的其他解决方案，但找不到。