public async Task GoBack_When_CanGoBack()
        {
            await ExecuteOnUIThread(() =>
            {
                var frame = new FrameFacadeAdapter(new Frame());
                var sessionStateService = new MockSessionStateService();
                sessionStateService.GetSessionStateForFrameDelegate = (currentFrame) => new Dictionary <string, object>();
                var navigationService = new FrameNavigationService(frame, (pageToken) => typeof(MockPage), sessionStateService);

                bool resultFirstNavigation = navigationService.Navigate("MockPage", 1);

                Assert.IsInstanceOfType(frame.Content, typeof(MockPage));
                Assert.AreEqual(1, ((MockPage)frame.Content).PageParameter);
                Assert.IsFalse(navigationService.CanGoBack());

                bool resultSecondNavigation = navigationService.Navigate("Mock", 2);

                Assert.IsInstanceOfType(frame.Content, typeof(MockPage));
                Assert.AreEqual(2, ((MockPage)frame.Content).PageParameter);
                Assert.IsTrue(navigationService.CanGoBack());

                navigationService.GoBack();

                Assert.IsInstanceOfType(frame.Content, typeof(MockPage));
                Assert.AreEqual(1, ((MockPage)frame.Content).PageParameter);
                Assert.IsFalse(navigationService.CanGoBack());
            });
        }
        public async Task Clear_History_Back_Button_Collapsed()
        {
            await DispatcherHelper.ExecuteOnUIThread(() =>
            {
                var eventAggregator     = new EventAggregator();
                var frame               = new FrameFacadeAdapter(new Frame(), eventAggregator);
                var sessionStateService = new MockSessionStateService();
                sessionStateService.GetSessionStateForFrameDelegate = (currentFrame) => new Dictionary <string, object>();
                var navigationService    = new FrameNavigationService(frame, (pageToken) => typeof(MockPage), sessionStateService);
                var deviceGestureService = new DeviceGestureService(eventAggregator);
                deviceGestureService.UseTitleBarBackButton = true;
                var navigationManager = SystemNavigationManager.GetForCurrentView();

                // Reset back button visibility before running, can't do this in TestInitialize because CoreWindow sometimes isn't ready
                SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility = AppViewBackButtonVisibility.Collapsed;

                Assert.AreEqual(AppViewBackButtonVisibility.Collapsed, navigationManager.AppViewBackButtonVisibility);

                navigationService.Navigate("Mock", 1);

                Assert.AreEqual(AppViewBackButtonVisibility.Collapsed, navigationManager.AppViewBackButtonVisibility);

                navigationService.Navigate("Mock", 2);

                Assert.AreEqual(AppViewBackButtonVisibility.Visible, navigationManager.AppViewBackButtonVisibility);

                Assert.IsTrue(navigationService.CanGoBack());

                navigationService.ClearHistory();

                Assert.AreEqual(AppViewBackButtonVisibility.Collapsed, navigationManager.AppViewBackButtonVisibility);
            });
        }
        public async Task GoBack_When_CanGoBack()
        {
            await ExecuteOnUIThread(() =>
            {
                var frame = new FrameFacadeAdapter(new Frame());
                var sessionStateService = new MockSessionStateService();
                sessionStateService.GetSessionStateForFrameDelegate = (currentFrame) => new Dictionary<string, object>();
                var navigationService = new FrameNavigationService(frame, (pageToken) => typeof(MockPage), sessionStateService);

                bool resultFirstNavigation = navigationService.Navigate("MockPage", 1);

                Assert.IsInstanceOfType(frame.Content, typeof(MockPage));
                Assert.AreEqual(1, ((MockPage)frame.Content).PageParameter);
                Assert.IsFalse(navigationService.CanGoBack());

                bool resultSecondNavigation = navigationService.Navigate("Mock", 2);

                Assert.IsInstanceOfType(frame.Content, typeof(MockPage));
                Assert.AreEqual(2, ((MockPage)frame.Content).PageParameter);
                Assert.IsTrue(navigationService.CanGoBack());

                navigationService.GoBack();

                Assert.IsInstanceOfType(frame.Content, typeof(MockPage));
                Assert.AreEqual(1, ((MockPage)frame.Content).PageParameter);
                Assert.IsFalse(navigationService.CanGoBack());
            });
        }
        public async Task Clear_History_Back_Button_Collapsed()
        {
            await DispatcherHelper.ExecuteOnUIThread(() =>
            {
                var eventAggregator = new EventAggregator();
                var frame = new FrameFacadeAdapter(new Frame(), eventAggregator);
                var sessionStateService = new MockSessionStateService();
                sessionStateService.GetSessionStateForFrameDelegate = (currentFrame) => new Dictionary<string, object>();
                var navigationService = new FrameNavigationService(frame, (pageToken) => typeof(MockPage), sessionStateService);
                var deviceGestureService = new DeviceGestureService(eventAggregator);
                deviceGestureService.UseTitleBarBackButton = true;
                var navigationManager = SystemNavigationManager.GetForCurrentView();

                // Reset back button visibility before running, can't do this in TestInitialize because CoreWindow sometimes isn't ready
                SystemNavigationManager.GetForCurrentView().AppViewBackButtonVisibility = AppViewBackButtonVisibility.Collapsed;

                Assert.AreEqual(AppViewBackButtonVisibility.Collapsed, navigationManager.AppViewBackButtonVisibility);

                navigationService.Navigate("Mock", 1);

                Assert.AreEqual(AppViewBackButtonVisibility.Collapsed, navigationManager.AppViewBackButtonVisibility);

                navigationService.Navigate("Mock", 2);

                Assert.AreEqual(AppViewBackButtonVisibility.Visible, navigationManager.AppViewBackButtonVisibility);

                Assert.IsTrue(navigationService.CanGoBack());

                navigationService.ClearHistory();

                Assert.AreEqual(AppViewBackButtonVisibility.Collapsed, navigationManager.AppViewBackButtonVisibility);
            });
        }