Kotlin Firebase Authentication – Google Sign In | Android

https://grokonez.com/android/kotlin-firebase-authentication-google-sign-in-android

Kotlin Firebase Authentication – Google Sign In | Android

In previous post, we had built a simple register/login Android App using Firebase Email & Password authentication. Now we can let users authenticate with Firebase using Google Accounts by integrating Google Sign In into Kotin Android App.

Related articles:

• Kotlin Firebase Authentication – How to Sign Up, Sign In, Sign Out, Verify Email | Android
• Kotlin Firebase Authentication – Send Reset Password Email / Forgot Password | Android

I. Way to do

1. Add Firebase to Android App

• Read Kotlin Firebase Authentication – How to Sign Up, Sign In, Sign Out, Verify Email | Android and follow steps to enable and implement Firebase Auth in your Android App.

• Add dependency: build.gradle (App-level):

  
  dependencies {
  // ...
  implementation 'com.google.android.gms:play-services-auth:11.0.4'
  }
  

  2. Enable Firebase Auth for Google Account

  Go to Your Firebase Project Console -> Authentication -> SIGN-IN METHOD -> Enable Google:
  

  3. Steps to authenticate with Firebase

  3.1 Integrate Google Sign In into App

  1- Add the Google Sign-In button:

  2- Configure Google Sign In object to request the user data:
  When you configure the GoogleSignInOptions object, call requestIdToken:

  
  override fun onCreate(savedInstanceState: Bundle?) {
  // ...
  
  val gso = GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
          .requestIdToken(WEB_CLIENT_ID)
          .requestEmail()
          .build()
  }

  With WEB_CLIENT_ID from Credentials page in the API Console -> OAuth 2.0 client IDs (Type Web Application).

3- Configure GoogleApiClient object with access to the Google Sign In API and the options above:

More at:

https://grokonez.com/android/kotlin-firebase-authentication-google-sign-in-android

Kotlin Firebase Authentication – Google Sign In | Android