在Android App中集成Google Sign-In。
參考鏈接：https://developers.google.com/identity/sign-in/android/start-integrating
Google API Console :https://console.developers.google.com

在開始集成之前:

1、你需要配置Google API Console.
2诽俯、設(shè)置你的Android Studio.

必備條件：

1川无、android設(shè)備需要Android 4.1及以上版本呛占，并且安裝Google Play 商店。
或者模擬器Android4.2.2以上版本懦趋，Google Play services 版本15.0.0以上
2晾虑、最新版本的Android SDK，安裝SDK Tools 組件仅叫。并且在Android Studio里面配置好SDK帜篇。
3、項(xiàng)目編譯版本在4.1以上版本诫咱。

以下是具體步驟：

一笙隙、添加 Google Play services

1、在project build.gradle 文件中, 確認(rèn)包含 Google's Maven坎缭。

allprojects {
    repositories {
        google()

        // If you're using a version of Gradle lower than 4.1, you must instead use:
        // maven {
        //     url 'https://maven.google.com'
        // }
    }
}

2竟痰、在app-level build.gradle 文件中, 定義 Google Play services :

apply plugin: 'com.android.application'
    ...

    dependencies {
        implementation 'com.google.android.gms:play-services-auth:17.0.0'
    }

二、配置一個(gè) Google API Console 項(xiàng)目
https://console.developers.google.com/apis/credentials
選擇android項(xiàng)目掏呼。
添入：SHA1值坏快。
獲取SHA1 keytool -keystore shooting.keystore -list -v

三、添加代碼
1憎夷、在onCreate中添加：

        // Configure sign-in to request the user's ID, email address, and basic
        // profile. ID and basic profile are included in DEFAULT_SIGN_IN.
        GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
                .requestEmail()
                .build();
        // Build a GoogleSignInClient with the options specified by gso.
        mGoogleSignInClient = GoogleSignIn.getClient(this, gso);

2莽鸿、添加cocos可以訪問的登錄方法：

/////google signin////////
public static void signInByGoogle() {
    Intent signInIntent = AppActivity._instance.mGoogleSignInClient.getSignInIntent();
    AppActivity._instance.startActivityForResult(signInIntent, RC_SIGN_IN);
}

////google sign-in
//在onActivityResult 中獲取對(duì)象 GoogleSignInAccount 
//After the user signs in, you can get a GoogleSignInAccount object for the user in the activity's onActivityResult method.
@Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        //facebook
        callbackManager.onActivityResult(requestCode, resultCode, data);
        super.onActivityResult(requestCode, resultCode, data);
        SDKWrapper.getInstance().onActivityResult(requestCode, resultCode, data);

        //google sign-in
        // Result returned from launching the Intent from GoogleSignInClient.getSignInIntent(...);
        if (requestCode == RC_SIGN_IN) {
            // The Task returned from this call is always completed, no need to attach
            // a listener.
            Task<GoogleSignInAccount> task = GoogleSignIn.getSignedInAccountFromIntent(data);
            handleSignInResult(task);
        }
    }

    ////google sign-in 
    //The GoogleSignInAccount object contains information about the signed-in user, such as the user's name.
    private void handleSignInResult(@NonNull Task<GoogleSignInAccount> completedTask) {
        Log.d(TAG, "handleSignInResult:" + completedTask.isSuccessful());

        try {
            GoogleSignInAccount account = completedTask.getResult(ApiException.class);
            updateUI(account);

        } catch (ApiException e) {
            Log.w(TAG, "handleSignInResult:error", e);

            // Clear the local account
            mAccount = null;

            // Signed out, show unauthenticated UI.
            updateUI(null);
        }
    }
    ////google sign-in 
    // 更新用戶信息
    void updateUI(GoogleSignInAccount account){
        if(account != null){
            // Store the account from the result
            mAccount = account;
            Log.d(TAG, "mAccount:" + mAccount);

            AppActivity._instance.runOnGLThread(new Runnable() {
                public void run(){
                    Cocos2dxJavascriptJavaBridge.evalString("yxl.loginSuccess(\"google"
                            + AppActivity._instance.mAccount.getId()
                            + "\",\""
                            + AppActivity._instance.mAccount.getDisplayName()
                            + "\",\""
                            +AppActivity._instance.mAccount.getPhotoUrl()
                            + "\",\""
                            +AppActivity._instance.displayCountryName
                            +"\");");
                }
            });
        }else{
            Log.d(TAG, "mAccount:null");
        }
    }