Dart using getter method to get private field valu

问题:

in this below class I have a private constructor with getter, unfortunately, I cant use this getter as userDao from outside of class, I get this error:

Instance member 'userDao' can't be accessed using static access.

class MydbModel {
  UserDao _userDao;

  MydbModel._(this._userDao);
  static Future<MydbModel> create() async => MydbModel._(await fn());

  static fn() {
    MyDatabase myDatabase = MyDatabase();
    myDatabase.initialDatabase();
    return myDatabase.getUserDao();
  }

  UserDao get userDao=>_userDao;
}

for example:

final UserDao userDao = MydbModel.userDao;

this implementation means i use await on this constructor without create new instance from that to use and define this codes:

MyDatabase myDatabase = MyDatabase();
myDatabase.initialDatabase();
return myDatabase.getUserDao();

for example:

class MyDatabase {
  AppDatabase db;
  UserDao userDao;

  Future<void> initialDatabase() async {
    db = await $FloorAppDatabase.databaseBuilder('flutter_database.db').build();
  }

  UserDao getUserDao() {
    return db.userDao;
  }
}

回答1:

final UserDao userDao = MydbModel.userDao;

You're trying to access an instance getter through the class. Either your getter and the private member need to be static or your need to construct an instance of MydbModel first.