안드로이드 스튜디오 구글 로그인

22 년 2 월 8 일

0. 연결할 안드로이드 앱 준비 

우측 Gradle에서 SH-1 복사해두기

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1. Firebase 프로젝트 생성

Firebase 프로젝트 생성, 앱 추가

google-services.json 파일 다운로드, 이동

 

project 수준의 gradle 추가

app 수준의 gradle 추가

 

Authentication/Sign-in method/Google 선택

프로젝트 공개용 이름, 이메일, SDK의 웹 클라이언트 ID 복사해둔다

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2. 앱이랑 연결

app 수준 gradle의 dependencies에 추가

implementation 'com.google.firebase:firebase-auth:19.1.0' 
implementation 'com.google.android.gms:play-services-auth:17.0.0'

AndroidManifast.xml 상단에 추가 (package 밑에)

<uses-permission android:name="android.permission.INTERNET"/>

 

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.memoex">
    <uses-permission android:name="android.permission.INTERNET"/>

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/Theme.MemoEx">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

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/SignIn_Button"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginTop="284dp"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintHorizontal_bias="0.0"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

MainActivity.java

public class MainActivity extends AppCompatActivity {

    private SignInButton signInButton;
    private GoogleSignInClient mGoogleSignInClient;
    private String TAG="mainTag";
    private FirebaseAuth mAuth;
    private int RC_SIGN_IN=123;

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

        signInButton = findViewById(R.id.SignIn_Button);

        // [START config_signin]
        // Configure Google Sign In
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestIdToken(getString(R.string.firebase_web_client_id))
                .requestEmail()
                .build();
        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);
        // [END config_signin]

        // [START initialize_auth]
        // Initialize Firebase Auth
        mAuth = FirebaseAuth.getInstance();
        // [END initialize_auth]

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

    // [START on_start_check_user]
    @Override
    public void onStart() {
        super.onStart();
        // Check if user is signed in (non-null) and update UI accordingly.
        FirebaseUser currentUser = mAuth.getCurrentUser();
        //updateUI(currentUser);
    }
    // [END on_start_check_user]

    @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);
            } catch (ApiException e) {
                // Google Sign In failed, update UI appropriately
                Log.w(TAG, "Google sign in failed", e);
                Toast.makeText(getApplicationContext(), "Google sign in Failed", Toast.LENGTH_LONG).show();
            }
        }
    }

    // [START auth_with_google]
    private void firebaseAuthWithGoogle(GoogleSignInAccount acct) {
        Log.d(TAG, "firebaseAuthWithGoogle:" + acct.getId());
        // [START_EXCLUDE silent]
        //showProgressDialog();
        // [END_EXCLUDE]

        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
                            Log.d(TAG, "signInWithCredential:success");
                            FirebaseUser user = mAuth.getCurrentUser();
                            //updateUI(user);
                            Toast.makeText(getApplicationContext(), "Complete", Toast.LENGTH_LONG).show();

                        } 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();
                            Toast.makeText(getApplicationContext(), "Authentication Failed", Toast.LENGTH_LONG).show();

                            // updateUI(null);
                        }

                        // [START_EXCLUDE]
                        // hideProgressDialog();
                        // [END_EXCLUDE]
                    }
                });
    }
    // [END auth_with_google]

    // [START signin]
    private void signIn() {
        Intent signInIntent = mGoogleSignInClient.getSignInIntent();
        startActivityForResult(signInIntent, RC_SIGN_IN);
    }
    // [END signin]

    private void signOut() {
        // Firebase sign out
        mAuth.signOut();

        // Google sign out
        mGoogleSignInClient.signOut().addOnCompleteListener(this,
                new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {
                        Toast.makeText(getApplicationContext(), "Complete", Toast.LENGTH_LONG).show();
                    }
                });
    }

    private void revokeAccess() {
        // Firebase sign out
        mAuth.signOut();

        // Google revoke access
        mGoogleSignInClient.revokeAccess().addOnCompleteListener(this,
                new OnCompleteListener<Void>() {
                    @Override
                    public void onComplete(@NonNull Task<Void> task) {
                        Toast.makeText(getApplicationContext(), "Complete", Toast.LENGTH_LONG).show();
                    }
                });
    }


}

---

string.xml

<resources>
    <string name="app_name">앱이름</string>
    <string name="firebase_web_client_id">아까 복사한 클라이언트 ID 복붙</string>
</resources>

google-services.json에서 클라이언트 ID 복사할 수 있고 아까 Console에서도 복사 가능 다른 글에 정리해둠

"oauth_client": [
        {
          "client_id": "154910

project 수준 build.gradle

// Top-level build file where you can add configuration options common to all sub-projects/modules.
buildscript {
    repositories {
        google()
        jcenter()
    }
    dependencies {
        classpath "com.android.tools.build:gradle:4.1.3"
        classpath 'com.google.gms:google-services:4.3.5'
        // NOTE: Do not place your application dependencies here; they belong
        // in the individual module build.gradle files
    }
}

allprojects {
    repositories {
        google()
        jcenter()
    }
}

task clean(type: Delete) {
    delete rootProject.buildDir
}

app 수준 build.gradle

plugins {
    id 'com.android.application'
}

apply plugin: 'com.android.application'
apply plugin: 'com.google.gms.google-services'

android {
    compileSdkVersion 30
    buildToolsVersion "30.0.3"

    defaultConfig {
        applicationId "com.example.memoex"
        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'
        }
    }
    compileOptions {
        sourceCompatibility JavaVersion.VERSION_1_8
        targetCompatibility JavaVersion.VERSION_1_8
    }
}

dependencies {

    implementation platform('com.google.firebase:firebase-bom:26.1.0')
    implementation 'com.google.firebase:firebase-analytics'
    implementation 'com.google.firebase:firebase-auth:19.1.0'
    implementation 'com.google.android.gms:play-services-auth:19.0.0'

    implementation 'androidx.appcompat:appcompat:1.2.0'
    implementation 'com.google.android.material:material:1.3.0'
    implementation 'androidx.constraintlayout:constraintlayout:2.0.4'
    testImplementation 'junit:junit:4.+'
    androidTestImplementation 'androidx.test.ext:junit:1.1.2'
    androidTestImplementation 'androidx.test.espresso:espresso-core:3.3.0'
}

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로그인 성공하면 이렇게 뜬다

지금 보니까 간단한데 날 너무 힘들게 했다......
그리고 updateUI 메서드가 없는데 왜 자꾸 updateUI를 호출하는 거지?
난 결국 updateUI 없는 코드로 로그인 성공함
구글 공식 문서를 봐도 어려워 developers.google.com/identity/sign-in/android/start-integrating

136번이 라이브러리 검색 후 추가 + 안드로이드 스튜디오에서 Firebase 연동이라 유용하게 쓰임
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