public MainWindowVM(EventAggregator eventAggregator, CustomerService customerService, ProductService productService, CategoryService categoryService, OrderService orderService, InventoryItemService inventoryService) { _customersVM = new CustomersVM(customerService); _customersVM.LoadCustomersCommand.Execute(null); _productsVM = new ProductsVM(productService, this); _productsVM.LoadProductsCommand.Execute(null); _categoriesVM = new CategoriesVM(categoryService); _categoriesVM.LoadCategoriesCommand.Execute(null); _ordersVM = new OrdersVM(orderService, this, eventAggregator); _ordersVM.LoadOrdersCommand.Execute(null); _inventoryItemsVM = new InventoryItemsVM(inventoryService, this); _inventoryItemsVM.LoadInventoryCommand.Execute(null); }