Google_Sign_In Package in Flutter

 Google Sign In

Flutter Package

Process - I

                    Package install : -  firebase_auth / firebase_core / google_sign_in

Process -II

                Create GoogleSignIn Class

import 'package:google_sign_in/google_sign_in.dart';
import 'package:firebase_auth/firebase_auth.dart';


class GoogleSignInClass{

 static final FirebaseAuth auth = FirebaseAuth.instance;
  static final GoogleSignIn googleSignIn=GoogleSignIn();

 static Future<dynamic> SignIn()async{
   final GoogleSignInAccount? googleSignInAccount=await googleSignIn.signIn();
   final GoogleSignInAuthentication? googleSignInAuthentication=await googleSignInAccount!.authentication;
   final AuthCredential credential=GoogleAuthProvider.credential(
     accessToken: googleSignInAuthentication!.accessToken,
     idToken: googleSignInAuthentication.idToken,
   );
   await auth.signInWithCredential(credential);
}

// Sign Out
static Future signOut()async{
   try{
     await auth.signOut();
   }catch(e){
     print(e);
   }
}

// User
static User getUser(){
   User user=auth.currentUser!;
   return user;
  }


}

Process - III

                    Use in Main File 

void main()async{

WidgetsFlutterBinding.ensureInitialized();
  await Firebase.initializeApp(
    options: FirebaseOptions(
        apiKey: "------------------",
        appId: "1:-------------------------1",
        messagingSenderId: "9-------------8",
        projectId: "f--------------d"
    ),
  );

                    Call SignIn Method on Button Pressed

       

ElevatedButton(

child: Text("Sign Up"),

onPressed: ()async{

await GoogleSignInClass.SignIn();

},

),