问触发Firebase [firebase_auth/网络请求-失败]网络错误(例如超时、中断连接或无法到达的主机)

EN

class Login extends StatefulWidget {
  static final String id = 'login_screen';
  const Login({Key? key}) : super(key: key);

  @override
  State<Login> createState() => _LoginState();
}

class _LoginState extends State<Login> {
  final GoogleSignIn googleSignIn = new GoogleSignIn();
  final FirebaseAuth firebaseAuth = FirebaseAuth.instance;
  late SharedPreferences preferences;
  bool loading = false;
  bool isLoggedIn = false;
  User? user;
  @override
  void initState() {
    super.initState();
    isSignedIn();
  }

  void isSignedIn() async {
    setState(() {
      // loading = true;
    });
    preferences = await SharedPreferences.getInstance();
    isLoggedIn = await googleSignIn.isSignedIn(); //Check if user is signed in

    if (isLoggedIn) {
      Navigator.pushReplacement(
          context,
          MaterialPageRoute(
              builder: (context) =>
                  HomePage())); //Helps us to keep user logged in once he has logged in so that user doesn't come to log in screen again on pressing back.
      setState(() {
        loading = false;
      });
    }
  }

  Future signInWithGoogle() async {
    preferences = await SharedPreferences.getInstance();
    setState(() {
      loading = true;
    });
    GoogleSignInAccount? googleUser = await googleSignIn.signIn();

    if (googleUser != null) {
     final GoogleSignInAuthentication googleSignInAuthentication =
          await googleUser.authentication;

      final AuthCredential credential = GoogleAuthProvider.credential(
        accessToken: googleSignInAuthentication.accessToken,
        idToken: googleSignInAuthentication.idToken,
      );
      final UserCredential userCredential =
          await firebaseAuth.signInWithCredential(credential);
      user = userCredential.user;
      if (user != null) {
        final QuerySnapshot result = await FirebaseFirestore.instance
            .collection("users")
            .where("id", isEqualTo: user?.uid)
            .get();
        //Check whether the id of that field is equal to the id of the user we obtained above.
        //If we have it, it means the user is already signed up to the application.
        final List<DocumentSnapshot> docs = result.docs;
        if (docs.length ==
            0) //If the docs are empty means that user does not exist in our database, therfore sign hom up
        {
          //Add user to our collection
          FirebaseFirestore.instance.collection("users").doc(user?.uid).set({
            "id": user?.uid,
            "username": user?.displayName,
            "profilePicture": user?.photoURL,
            "phNo": user?.phoneNumber,
            "email": user?.email,
          });
          await preferences.setString('id', user!.uid);
          await preferences.setString('userName', user!.displayName ?? ' ');
          await preferences.setString('photoUrl', user!.photoURL ?? ' ');
          await preferences.setString('email', user!.email ?? '');
        } else {
          await preferences.setString('id', docs[0]['id']);
          await preferences.setString('userName', docs[0]['username']);
          await preferences.setString('photoUrl', docs[0]['photoUrl']);
          await preferences.setString('email', docs[0]['email']);
        }
        Navigator.popAndPushNamed(context, HomePage.id);
        setState(() {
          loading = false;
        });

      } else {}

      
    }
  }