public void DeleteAsync_ItemNull()
        {
            CollectionPageViewModel <Uom> viewModel = new ViewModelTestBuilder <Uom>()
                                                      .SetConstructor_Title("Uoms")
                                                      .NewPageService_NotCalled()
                                                      .ReadPageService_NotCalled()
                                                      .DeleteService_NotCalled();

            Assert.ThrowsAsync <ArgumentNullException>
            (
                async() => await viewModel.DeleteAsync(null)
            );
        }
        public async Task DeleteAsync()
        {
            var page = PageMaker.GetExpectedPage(
                data: UomTestData.GetUomsArray(),
                searchText: string.Empty,
                skip: 0,
                take: 20
                );
            var expectedPage = CollectionPageDataMaker.GetExpectedPage(page, "http://localhost/api");

            CollectionPageViewModel <Uom> viewModel = new ViewModelTestBuilder <Uom>()
                                                      .SetConstructor_Title("Uoms")
                                                      .Then_NewPageService_ReadPageAsync("", expectedPage)
                                                      .Then_DeleteService_DeleteItemAsync(1001)
                                                      .Then_ReadPageService_RefreshCurrentPageAsync(expectedPage);

            await viewModel.SearchAsync("");

            Assert.True(CollectionPageViewModelChecker.Check(expectedPage, viewModel, UomEqual.Check));
            await viewModel.DeleteAsync(new Uom().WithId(1001));

            Assert.True(CollectionPageViewModelChecker.Check(expectedPage, viewModel, UomEqual.Check));
        }