Skip to main content

Setting Up Firebase for Google Authentication in Flutter

To integrate Google Authentication into your Flutter app using Firebase, follow the steps below.

1. Create a Firebase Project​

  1. Sign in to Firebase Console: Navigate to the Firebase Console and sign in with your Google account.
  2. Add a New Project: Click on "Add project" and follow the on-screen instructions to create a new project.

2. Register Your App with Firebase​

For Android:​

  1. Add Android App: In the Firebase Console, select your project, then click on the Android icon to add an Android app.
  2. Register App: Enter your app's package name (found in your Flutter project's android/app/src/main/AndroidManifest.xml), and provide a nickname and SHA-1 key if needed.
  3. Download google-services.json: After registering, download the google-services.json file and place it in your Flutter project at android/app/.
  4. Modify build.gradle Files:
    • Project-level (android/build.gradle): Add the classpath to the dependencies section.
    • App-level (android/app/build.gradle): Apply the Google services plugin and add the google-services.json file.

For iOS:​

  1. Add iOS App: In the Firebase Console, click on the iOS icon to add an iOS app.
  2. Register App: Enter your iOS bundle ID (found in ios/Runner.xcodeproj), and provide other required information.
  3. Download GoogleService-Info.plist: After registering, download the GoogleService-Info.plist file and place it in your Flutter project at ios/Runner/.
  4. Modify ios/Podfile: Ensure the platform is set to iOS 10 or later.
  5. Install Pods: Run pod install in the ios directory.

3. Enable Google Sign-In in Firebase​

  1. Navigate to Authentication: In the Firebase Console, go to the "Authentication" section.
  2. Set Up Sign-In Method: Under the "Sign-in method" tab, enable "Google" as a sign-in provider and configure the necessary settings.

4. Initialize Firebase in Your Flutter App​

In your main.dart file, ensure that Firebase is initialized before running the app.

5. Implement Google Sign-In​

Utilize the firebase_auth and google_sign_in packages to handle authentication.

6. Test Authentication​

Run your app on a device or emulator to test the Google Sign-In functionality. Ensure that the Google account used is added as a tester in your Firebase project if your app isn't publicly released.

For more detailed information, refer to the Firebase Authentication for Flutter guide.