public async void DeleteProduct(ProductItem productItem)
        {
            Product deletedProduct = null;

            using (UserDialogs.Instance.Loading("Deleting.."))
            {
                //update product ở database local
                deletedProduct = DataUpdater.DeleteProductInStore(productItem.Product);
                //update product ở database server
                await httpClient.PostAsJsonAsync(ServerDatabase.localhost + "product/update", deletedProduct);

                LoadProducts(false);
            }

            MessageService.Show("Delete product successfully", 0);
            //PUSH NOTI
            string datas = PushNotificationService.ConvertDataUpdateProduct(deletedProduct);

            PushNotificationService.Push(NotiNumber.UpdateProduct, datas, true);
        }