firebase 파이어베이스 구글로그인 연동하기

시작 전에, 안드로이드 프로젝트에 firebase 추가는 필수. 안했다면 하단의 링크 참고

Android 프로젝트에 Firebase 추가 (google.com)

Android 프로젝트에 Firebase 추가

 

 

activity_main

<com.google.android.gms.common.SignInButton
        android:id="@+id/login_Button"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="304dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

 

Authentication 가서 Google - 사용 설정도 잊지 말아야 한다.

 

 

 

 

 

MainActivity.java

package com.example.startfirebasestudy;

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

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

import com.google.android.gms.auth.api.Auth;
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.GoogleSignInOptions;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.ApiException;
import com.google.android.gms.common.api.GoogleApiClient;
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.GoogleAuthProvider;

import static android.content.ContentValues.TAG;

public class MainActivity extends AppCompatActivity implements GoogleApiClient.OnConnectionFailedListener{

    private static final int RC_SIGN_IN = 10;
    private GoogleApiClient mGoogleApiClient;
    private FirebaseAuth mAuth;

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


        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, this)
                .addApi(Auth.GOOGLE_SIGN_IN_API,gso)
                .build();

        SignInButton button = (SignInButton)findViewById(R.id.login_Button);
        button.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View view){
                Intent signIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
                startActivityForResult(signIntent,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 {
                // 구글 사용자가 맞으면 파이어베이스로 넘김
                GoogleSignInAccount account = task.getResult(ApiException.class);
                Log.d(TAG, "firebaseAuthWithGoogle:" + account.getId());
                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) {

        //정보 전달 받음
        AuthCredential credential = GoogleAuthProvider.getCredential(idToken, null);
        mAuth.signInWithCredential(credential)
                //파이어베이스로 정보가 넘어간다
                .addOnCompleteListener(this, new OnCompleteListener<AuthResult>() {
                    @Override
                    public void onComplete(@NonNull Task<AuthResult> task) {
                        if (!task.isSuccessful()) {
                        }else{
                        Toast.makeText(MainActivity.this, "FireBase아이디 생성이 완료 되었습니다.",Toast.LENGTH_SHORT).show();
                    }
                    }
                });
    }


    @Override
    public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

    }
}

 

 

 

 

실행화면

Sign in 버튼이 나온다. 이걸 누르면

 

 

다음과 같이 구글 계정으로 로그인이 가능