[Windows] Fixed IsEnabled Property not works on Tabs

src/Controls/src/Core/Handlers/Shell/ShellItemHandler.Windows.cs

@@ -115,11 +115,19 @@ protected override void DisconnectHandler(FrameworkElement platformView)
 			}
 
 			if (_shellItem is IShellItemController shellItemController)
+			{
 				shellItemController.ItemsCollectionChanged -= OnItemsChanged;
 
-			if (VirtualView.Parent is Shell shell)
-			{
-				shell.Navigated -= OnShellNavigated;
+				if (VirtualView.Parent is Shell shell)
+				{
+					shell.Navigated -= OnShellNavigated;
+				}
+
+				foreach (var item in shellItemController.GetItems())
+				{
+					item.PropertyChanged -= OnShellItemPropertyChanged;
+				}
+
 			}
 		}
 
@@ -203,6 +211,7 @@ internal void MapMenuItems()
 
 			foreach (var item in shellItemController.GetItems())
 			{
+				item.PropertyChanged += OnShellItemPropertyChanged;
 				if (Routing.IsImplicit(item))
 					items.Add(item.CurrentItem);
 				else
@@ -254,6 +263,7 @@ internal void MapMenuItems()
 				void SetValues(BaseShellItem bsi, NavigationViewItemViewModel vm)
 				{
 					vm.Content = bsi.Title;
+					vm.IsEnabled = bsi.IsEnabled;
 					var iconSource = bsi.Icon?.ToIconSource(MauiContext!);
 
 					if (iconSource != null)
@@ -409,6 +419,33 @@ void OnSearchBoxQuerySubmitted(Microsoft.UI.Xaml.Controls.AutoSuggestBox sender,
 			}
 		}
 
+		void OnShellItemPropertyChanged(object? sender, PropertyChangedEventArgs e)
+		{
+			if (_mainLevelTabs == null || sender is not BaseShellItem shellItem)
+			{
+				return;
+			}
+
+			for (int i = 0; i < _mainLevelTabs.Count; i++)
+			{
+				if (_mainLevelTabs[i].Data != sender)
+				{
+					continue;
+				}
+
+				switch (e.PropertyName)
+				{
+					case nameof(BaseShellItem.IsEnabled):
+						_mainLevelTabs[i].IsEnabled = shellItem.IsEnabled;
+						break;
+					case nameof(BaseShellItem.Title):
+						_mainLevelTabs[i].Content = shellItem.Title;
+						break;
+				}
+				return;
+			}
+		}
+
 		void OnCurrentSearchHandlerPropertyChanged(object? sender, PropertyChangedEventArgs e)
 		{
 			if (_currentSearchHandler is null)

src/Controls/src/Core/Platform/Windows/TabbedPage/TabbedPageStyle.xaml

@@ -7,6 +7,7 @@
             x:Name="navViewItem"
             Content="{Binding Content}"
             Background="{Binding Background}" 
+            IsEnabled="{Binding IsEnabled}"
             IsSelected="{Binding IsSelected, Mode=TwoWay}"
             MenuItemsSource="{Binding MenuItemsSource}"
             Icon="{Binding Icon}"

src/Controls/src/Core/TabbedPage/TabbedPage.Windows.cs

@@ -379,6 +379,7 @@ internal static void MapItemsSource(ITabbedViewHandler handler, TabbedPage view)
 						vm.SelectedForeground = view.SelectedTabColor?.AsPaint()?.ToPlatform();
 						vm.UnselectedForeground = view.UnselectedTabColor?.AsPaint()?.ToPlatform();
 						vm.IsSelected = page == view.CurrentPage;
+						vm.IsEnabled = page.IsEnabled;
 					});
 
 				handler.UpdateValue(nameof(TabbedPage.CurrentPage));

src/Controls/tests/TestCases.HostApp/Issues/Issue5161.cs

@@ -0,0 +1,133 @@
+using System;
+using Microsoft.Maui.Controls;
+
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 5161, "ShellContent IsEnabledProperty does not work", PlatformAffected.iOS)]
+public class Issue5161 : Shell
+{
+    public Issue5161()
+    {
+        var mainPageTab = new Tab
+        {
+            Title = "FirstPage",
+            IsEnabled = true,
+        };
+        mainPageTab.Items.Add(new ShellContent
+        {
+            ContentTemplate = new DataTemplate(() => new Issue5161_MainPage())
+        });
+
+        var secondPageTab = new Tab
+        {
+            Title = "SecondTab",
+            IsEnabled = false,
+            AutomationId = "SecondTab"
+        };
+        secondPageTab.Items.Add(new ShellContent
+        {
+            ContentTemplate = new DataTemplate(() => new SecondPage())
+        });
+        var thirdTab = new Tab
+        {
+            Title = "ThirdTab",
+            IsEnabled = true,
+            AutomationId = "ThirdTab"
+        };
+        thirdTab.Items.Add(new ShellContent
+        {
+            ContentTemplate = new DataTemplate(() => new ThirdPage())
+        });
+        var tabBar = new TabBar();
+        tabBar.Items.Add(mainPageTab);
+        tabBar.Items.Add(secondPageTab);
+        tabBar.Items.Add(thirdTab);
+        Items.Add(tabBar);
+    }
+
+    public class Issue5161_MainPage : ContentPage
+    {
+        public Issue5161_MainPage()
+        {
+            Content = new StackLayout
+            {
+                VerticalOptions = LayoutOptions.Center,
+                HorizontalOptions = LayoutOptions.Center,
+                Children =
+            {
+                new Label
+                {
+                    Text = "This is First Page",
+                }
+            }
+            };
+        }
+    }
+
+    public class SecondPage : ContentPage
+    {
+        public SecondPage()
+        {
+            Content = new StackLayout
+            {
+                VerticalOptions = LayoutOptions.Center,
+                HorizontalOptions = LayoutOptions.Center,
+                Children =
+            {
+                new Label
+                {
+                    Text = "This is Second Page",
+                    AutomationId = "SecondPageLabel"
+                }
+            }
+            };
+        }
+    }
+    public class ThirdPage : ContentPage
+    {
+        public ThirdPage()
+        {
+            var label = new Label
+            {
+                Text = "This is Third Page",
+                HorizontalOptions = LayoutOptions.Center,
+                VerticalOptions = LayoutOptions.Center,
+                AutomationId = "ThirdPageLabel"
+            };
+
+            var button = new Button
+            {
+                Text = "Enable SecondTab",
+                HorizontalOptions = LayoutOptions.Center,
+                VerticalOptions = LayoutOptions.Center,
+                AutomationId = "EnableSecondTab"
+            };
+            button.Clicked += OnButtonClicked;
+            Content = new StackLayout
+            {
+                VerticalOptions = LayoutOptions.Center,
+                HorizontalOptions = LayoutOptions.Center,
+                Children =
+            {
+                label,
+                button
+            }
+            };
+        }
+
+        private void OnButtonClicked(object sender, EventArgs e)
+        {
+            if (Application.Current?.Windows.Count > 0 &&
+                Application.Current.Windows[0].Page is Shell shell)
+            {
+                var secondTab = shell.CurrentItem?.Items[1];
+                if (secondTab is not null)
+                    secondTab.IsEnabled = true;
+            }
+            else
+            {
+                System.Diagnostics.Debug.WriteLine("Shell not found!");
+            }
+        }
+    }
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue5161.cs

@@ -0,0 +1,28 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue5161 : _IssuesUITest
+{
+	public Issue5161(TestDevice testDevice) : base(testDevice)
+	{
+	}
+
+	public override string Issue => "ShellContent IsEnabledProperty does not work";
+
+	[Test]
+	[Category(UITestCategories.Shell)]
+	public void CheckIsEnabled()
+	{
+		App.WaitForElement("ThirdTab");
+		App.Tap("ThirdTab");
+		App.WaitForElement("ThirdPageLabel");
+		App.Tap("SecondTab");
+		App.WaitForNoElement("SecondPageLabel");
+		App.Tap("EnableSecondTab");
+		App.Tap("SecondTab");
+		App.WaitForElement("SecondPageLabel");
+	}
+}

src/Core/src/Platform/Windows/NavigationViewItemViewModel.cs

@@ -82,6 +82,7 @@ internal class NavigationViewItemViewModel : INotifyPropertyChanged
 
 		object? _content;
 		bool _isSelected;
+		bool _isEnabled;
 		WBrush? _selectedBackground;
 		WBrush? _unselectedBackground;
 		WBrush? _selectedForeground;
@@ -232,6 +233,18 @@ public bool IsSelected
 			}
 		}
 
+		public bool IsEnabled
+		{
+			get => _isEnabled;
+			set
+			{
+				if (_isEnabled != value)
+				{
+					_isEnabled = value;
+					OnPropertyChanged(nameof(IsEnabled));
+				}
+			}
+		}
 		void OnPropertyChanged(string args) =>
 			OnPropertyChanged(new PropertyChangedEventArgs(args));