LateInitializationError：字段“_preferences@56516396”尚未初始化

Question

I think, the given error "LateInitializationError: Field '_preferences@56516396' has not been initialized.", is in this code. I don't get the error correctly where is that, That's why I want your help to find it.

import 'dart:convert';

import 'package:buis_talk/screens/profile/model/user.dart';
import 'package:shared_preferences/shared_preferences.dart';

class UserPreferences {
  static late SharedPreferences _preferences;

  static const _keyUser = 'user';
  static const myUser = Usercard(
    imageUrls:
        'https://images.unsplash.com/photo-1554151228-14d9def656e4?ixid=MnwxMjA3fDB8MHxwaG90by1wYWdlfHx8fGVufDB8fHx8&ixlib=rb-1.2.1&auto=format&fit=crop&w=333&q=80',
    name: 'Sarah Abs',
    email: 'sarah.abs@gmail.com',
    about:
        'Certified Personal Trainer and Nutritionist with years of experience in creating effective diets and training plans focused on achieving individual customers goals in a smooth way.',
    profession: 'Entrepreneur',
    interests: 'Stocks | Crypto | NFT\'s',
    location: 'Delhi, India',
  );

  static Future init() async =>
    _preferences = await SharedPreferences.getInstance();

  static Future setUser(Usercard user)async {
    final json = jsonEncode(user.toJson());

  await _preferences.setString(_keyUser, json);
  }

  static Usercard getUsercard() {
    final json = _preferences.getString(_keyUser);

    return json == null ? myUser : Usercard.fromJson(jsonDecode(json));
  }
}

This is the profile screen which is the main screen that display on the android screen.

class ProfilePage extends StatefulWidget {
  static const String routeName = '/profile';
  const ProfilePage({ Key? key }) : super(key: key);

  static Route route() {
    return MaterialPageRoute(
      settings: const RouteSettings(name: routeName),
      builder: (context) => const ProfilePage(),
    );
  }

  @override
  State<ProfilePage> createState() => _ProfilePageState();
}

class _ProfilePageState extends State<ProfilePage> {
  @override
  Widget build(BuildContext context) {
    final usercard = UserPreferences.getUsercard();

This is the second screen that is edit screen.

class EditProfilePage extends StatefulWidget {
  const EditProfilePage({Key? key}) : super(key: key);

  @override
  _EditProfilePageState createState() => _EditProfilePageState();
}

class _EditProfilePageState extends State<EditProfilePage> {
  Usercard user = UserPreferences.myUser;
  // late Usercard user;

  @override
  void initState() {
    super.initState();

    user = UserPreferences.getUsercard();
  }

Error could be on any screen from these but I don't know on which particular step it gives me error.

This is the android screen. The error shown like this on screen.

Answer 1

You dont use the init function. You need the use this in initState

 @override
  void initState() {
    super.initState();
    UserPreferences.init();
    user = UserPreferences.getUsercard();
  }