private void CheckOut()
        {
            var master = Application.Current.MainPage as Views.Core.Layout;
            //set order info vm here
            SalesOrder so = new SalesOrder()
            {
                Date = DateTime.Now, CustomerID = Config.Instance.Auth.UserID.ToString()
            };

            foreach (var order in cart)
            {
                so.AddDetail(order);
            }

            master.SetDetailPage(new NewOrderCheckOut()
            {
                Title = "Check Out", BindingContext = new NewOrderCheckOutViewModel(so)
            });
        }