Firebase authenthication

Im trying to use firebase for my flutter apps, and its seem there is an error in my code , i know firebaseuser need to change to user, but its seem it does not work , please help me , im new.

import 'package:firebase_auth/firebase_auth.dart';
import 'package:quizmaker/view/signin.dart';
import 'package:quizmaker/models/user.dart';

class AuthService {
  FirebaseAuth _auth = FirebaseAuth.instance;

  Future signInEmailAndPass(String email, String password) async {
    try {
      UserCredential userCredential = await _auth.signInWithEmailAndPassword(
          email: email, password: password);
      User user = authResult.user; //the error is in this part
    } catch (e) {
      print(e.toString());
    }
  }
}

In this code snippet:

  UserCredential userCredential = await _auth.signInWithEmailAndPassword(
      email: email, password: password);
  User user = authResult.user;

You're trying to use an authResult variable that is never defined. My best guess is that you want to get the user from the userCredential instead, so:

  UserCredential userCredential = await _auth.signInWithEmailAndPassword(
      email: email, password: password);
  User user = userCredential.user;

This still won't work though, since userCredential.user may be null, and is thus defined as User? and not User. Since you're using await, you can be certain that there is a user, so you can do:

  User user = userCredential.user!;