using BeautySalonDatabaseImplement.Models; namespace BeautySalonListImplement { public class DataListSingleton { private static DataListSingleton? _instance; public List Clients { get; set; } public List Cosmetics { get; set; } public List Distributions { get; set; } public List Employees { get; set; } public List Procedures { get; set; } public List Purchases { get; set; } public List Receipts { get; set; } public List Visits { get; set; } private DataListSingleton() { Clients = new List(); Cosmetics = new List(); Distributions = new List(); Employees = new List(); Procedures = new List(); Purchases = new List(); Receipts = new List(); Visits = new List(); } public static DataListSingleton GetInstance() { if (_instance == null) { _instance = new DataListSingleton(); } return _instance; } } }