public SaleShowViewModel()
{
_saleServ = new SaleServices();
_categoryServ = new CategoryServices();
_saleRecallServ = new SaleRecallServices();
_saleCategoryServ = new SaleCategoryServices();
_clientAccountServ = new ClientAccountServices();
_saleRecallDialog = new SaleRecallDialog();
_state = "Normal";
_isFocused = true;
_currentWindow = Application.Current.Windows.OfType <MetroWindow>().LastOrDefault();
_selectedSale = _saleServ.GetSale(ID);
_saleCategories = new ObservableCollection <SaleCategoryVM>(_saleCategoryServ.GetSaleCategoriesVM(ID));
_categories = new ObservableCollection <SaleRecallVM>(_saleRecallServ.GetSaleCategoriesVM(ID));
RecallsQty = _saleRecallServ.GetSaleRecallsSum(ID);
Report = "تقرير الفاتورة";
}