public void GroupingInListBoxTest()
        {
            ObservableCollection <TestClass> collection = new ObservableCollection <TestClass>()
            {
                new TestClass {
                    IntProperty = 1, StringProperty = "A"
                },
                new TestClass {
                    IntProperty = 2, StringProperty = "B"
                },
                new TestClass {
                    IntProperty = 3, StringProperty = "A"
                },
                new TestClass {
                    IntProperty = 4, StringProperty = "B"
                }
            };

            PagedCollectionView cv = new PagedCollectionView(collection);

            ListBox lb = new ListBox();

            lb.ItemsSource = cv;

            this.CreateAsyncTask(
                lb,
                delegate
            {
                Assert.AreEqual(4, lb.Items.Count);

                cv.GroupDescriptions.Add(new PropertyGroupDescription("StringProperty"));

                Assert.AreEqual(4, lb.Items.Count);
                Assert.AreEqual("A", (lb.Items[0] as TestClass).StringProperty);
                Assert.AreEqual("A", (lb.Items[1] as TestClass).StringProperty);
                Assert.AreEqual("B", (lb.Items[2] as TestClass).StringProperty);
                Assert.AreEqual("B", (lb.Items[3] as TestClass).StringProperty);

                cv.PageSize = 3;
                cv.MoveToPage(1);

                Assert.AreEqual(1, lb.Items.Count);
                Assert.AreEqual("B", (lb.Items[0] as TestClass).StringProperty);

                TestClass newItem      = cv.AddNew() as TestClass;
                newItem.StringProperty = "A";
                newItem.IntProperty    = 5;

                // ---------------------
                // |Page | 0  | 1  | 2  |
                // ---------------------
                // | 0   | A  | A  | B  |
                // | 1   | B  |-A- |    | <---- Current Page
                Assert.AreEqual("B", (lb.Items[0] as TestClass).StringProperty);
                Assert.AreEqual("A", (lb.Items[1] as TestClass).StringProperty);
                cv.CommitNew();

                // ---------------------
                // |Page | 0  | 1  | 2  |
                // ---------------------
                // | 0   | A  | A  |-A- |
                // | 1   | B  | B  |    | <---- Current Page
                Assert.AreEqual("B", (lb.Items[0] as TestClass).StringProperty);
                Assert.AreEqual("B", (lb.Items[1] as TestClass).StringProperty);

                cv.MoveToFirstPage();
                Assert.AreEqual("A", (lb.Items[0] as TestClass).StringProperty);
                Assert.AreEqual("A", (lb.Items[1] as TestClass).StringProperty);
                Assert.AreEqual("A", (lb.Items[2] as TestClass).StringProperty);
            });

            EnqueueTestComplete();
        }