[Kotlin] 파이어베이스 구글 로그인

파이어베이스 구글 로그인

 

파이어베이스는 구글 (Google)이 소유하고 있는 모바일 애플리케이션 개발 플랫폼이다. 구글 로그인 인증을 구현하기 위해 파이어베이스 구성 파일과 SDK를 추가한다. 프로젝트를 위해 login 페이지와 login 후의 페이지를 구성한다.

 

build.gradle

 

implementation platform('com.google.firebase:firebase-bom:31.1.1')
implementation 'com.google.firebase:firebase-auth-ktx:21.1.0'
implementation 'com.google.firebase:firebase-storage-ktx:20.0.1'
implementation 'com.google.firebase:firebase-analytics-ktx'
implementation 'com.google.android.gms:play-services-auth:20.4.0'

 

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"

	<com.google.android.gms.common.SignInButton
        android:id="@+id/btnSignIn"
        android:layout_width="271dp"
        android:layout_height="66dp"/>
        
</androidx.constraintlayout.widget.ConstraintLayout>

 

class : login

 

import android.content.Intent
import android.os.Bundle
import android.view.animation.AnimationUtils
import android.widget.ImageView
import androidx.activity.result.contract.ActivityResultContracts
import androidx.appcompat.app.AppCompatActivity
import com.google.android.gms.auth.api.signin.GoogleSignIn
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.firebase.auth.FirebaseAuth
import com.google.firebase.auth.FirebaseUser
import com.google.firebase.auth.GoogleAuthProvider

class intro : AppCompatActivity() {
    lateinit var googleSignInClient: GoogleSignInClient
    lateinit var auth : FirebaseAuth
    lateinit var imageview : ImageView
    val binding by lazy {ActivityIntroBinding.inflate(layoutInflater)}
    
    var googleLoginReult = registerForActivityResult(ActivityResultContracts.StartActivityForResult()){
        result ->

        var data = result.data
        var task = GoogleSignIn.getSignedInAccountFromIntent(data)
        val account = task.getResult(ApiException::class.java)
        firebaseAuthWithGoogle(account.idToken)
    }

    fun firebaseAuthWithGoogle(idToken: String?){
        var credential = GoogleAuthProvider.getCredential(idToken, null)

        auth.signInWithCredential((credential)).addOnCompleteListener{
            task ->
            if(task.isSuccessful){
                moveMainPage(task.result?.user)
            }
        }
    }
    
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(binding.root)

        auth = FirebaseAuth.getInstance()

        binding.btnSignIn.setOnClickListener{
            signIn()
        }

        val gso = GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
            .requestIdToken(getString(R.string.default_web_client_id))
            .requestEmail()
            .requestProfile()
            .build()
            
        googleSignInClient = GoogleSignIn.getClient(this, gso)
        
    }
    
    private fun signIn() {
        val i = googleSignInClient.signInIntent
        googleLoginReult.launch(i)
    }

    //로그인 activity에서 Main으로
    fun moveMainPage(user: FirebaseUser?){
        if (user != null){
            startActivity(Intent(this,MainActivity::class.java))
        }
    }
}