[iOS][Shell] Fix navigation lifecycle and back button for More tab (>5 tabs)

src/Controls/src/Core/Compatibility/Handlers/Shell/iOS/ShellSectionRenderer.cs

@@ -119,15 +119,16 @@ bool DidPopItem(UINavigationBar _, UINavigationItem __)
 			return SendPop();
 		}
 
-		internal bool SendPop()
+		internal bool SendPop(UIViewController topViewController = null)
 		{
 			// this means the pop is already done, nothing we can do
 			if (ActiveViewControllers().Length < NavigationBar.Items.Length)
 				return true;
 
+			topViewController ??= TopViewController;
 			foreach (var tracker in _trackers)
 			{
-				if (tracker.Value.ViewController == TopViewController)
+				if (tracker.Value.ViewController == topViewController)
 				{
 					var behavior = Shell.GetEffectiveBackButtonBehavior(tracker.Value.Page);
 					var command = behavior.GetPropertyIfSet<ICommand>(BackButtonBehavior.CommandProperty, null);
@@ -611,6 +612,8 @@ public override void PushViewController(UIViewController viewController, bool an
 			if (IsInMoreTab && ParentViewController is UITabBarController tabBarController)
 			{
 				tabBarController.MoreNavigationController.PushViewController(viewController, animated);
+				viewController.NavigationItem.BackAction = UIAction.Create((e) => SendPop(tabBarController.MoreNavigationController.TopViewController));
+				HandleMoreNavigationCompletionTasks(viewController);
 			}
 			else
 			{
@@ -623,12 +626,30 @@ public override UIViewController PopViewController(bool animated)
 			_pendingViewControllers = null;
 			if (IsInMoreTab && ParentViewController is UITabBarController tabBarController)
 			{
-				return tabBarController.MoreNavigationController.PopViewController(animated);
+				var viewController = tabBarController.MoreNavigationController.PopViewController(animated);
+				HandleMoreNavigationCompletionTasks(viewController);
+				return viewController;
 			}
 
 			return base.PopViewController(animated);
 		}
 
+		private void HandleMoreNavigationCompletionTasks(UIViewController viewController)
+		{
+			var tasks = _completionTasks;
+			var popTask = _popCompletionTask;
+
+			if (tasks.TryGetValue(viewController, out var source))
+			{
+				source.TrySetResult(true);
+				tasks.Remove(viewController);
+			}
+			else if (popTask != null)
+			{
+				popTask.TrySetResult(true);
+			}
+		}
+
 		UIViewController[] ActiveViewControllers() =>
 			_pendingViewControllers ?? base.ViewControllers;
 

src/Controls/tests/TestCases.HostApp/Issues/Issue27799.cs

@@ -0,0 +1,74 @@
+namespace Maui.Controls.Sample.Issues
+{
+
+	[Issue(IssueTracker.Github, 27799, "[iOS] OnAppearing and OnNavigatedTo does not work when using extended Tabbar", PlatformAffected.iOS)]
+
+	public class Issue27799 : TestShell
+	{
+		private static int _onNavigatedToCount = 0;
+		private static int _onAppearingCount = 0;
+
+		protected override void Init()
+		{
+			Routing.RegisterRoute(nameof(Tab6Subpage), typeof(Tab6Subpage));
+			AddBottomTab("tab1");
+			AddBottomTab(new Tab2(), "tab2");
+			AddBottomTab("tab3");
+			AddBottomTab("tab4");
+			AddBottomTab("tab5");
+			AddBottomTab(new Tab6(), "Tab6");
+		}
+
+		class Tab2 : ContentPage
+		{
+			Label _onNavigatedToCountLabel;
+			Label _onAppearingCountLabel;
+			public Tab2()
+			{
+				_onNavigatedToCountLabel = new Label { AutomationId = "OnNavigatedToCountLabel", Text = $"OnNavigatedTo: {_onNavigatedToCount}" };
+				_onAppearingCountLabel = new Label { AutomationId = "OnAppearingCountLabel", Text = $"OnAppearing: {_onAppearingCount}" };
+				Content = new StackLayout
+				{
+					Children =
+					{
+						_onNavigatedToCountLabel,
+						_onAppearingCountLabel
+					}
+				};
+			}
+
+			protected override void OnNavigatedTo(NavigatedToEventArgs e)
+			{
+				_onNavigatedToCount++;
+				_onNavigatedToCountLabel.Text = $"OnNavigatedTo: {_onNavigatedToCount}";
+			}
+
+			protected override void OnAppearing()
+			{
+				_onAppearingCount++;
+				_onAppearingCountLabel.Text = $"OnAppearing: {_onAppearingCount}";
+			}
+		}
+
+		class Tab6 : ContentPage
+		{
+			public Tab6()
+			{
+				Content = new Button
+				{
+					Text = "Go to subpage6",
+					AutomationId = "GoToSubpage6Button",
+					Command = new Command(async () => await Current.GoToAsync(nameof(Tab6Subpage)))
+				};
+			}
+			protected override void OnNavigatedTo(NavigatedToEventArgs e) => _onNavigatedToCount++;
+			protected override void OnAppearing() => _onAppearingCount++;
+		}
+
+		class Tab6Subpage : ContentPage
+		{
+			protected override void OnNavigatedTo(NavigatedToEventArgs e) => _onNavigatedToCount++;
+			protected override void OnAppearing() => _onAppearingCount++;
+		}
+	}
+}

src/Controls/tests/TestCases.HostApp/Issues/Issue27800.cs

@@ -0,0 +1,72 @@
+#if ANDROID || IOS
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 27800, "Shell.BackButtonBehavior does not work when using extended Tabbar", PlatformAffected.iOS)]
+public class Issue27800 : TestShell
+{
+
+	protected override void Init()
+	{
+		Routing.RegisterRoute(nameof(Tab6DetailPage), typeof(Tab6DetailPage));
+		AddBottomTab("tab1");
+		AddBottomTab("tab2");
+		AddBottomTab("tab3");
+		AddBottomTab("tab4");
+		AddBottomTab("tab5");
+		AddBottomTab(new Tab6(), "tab6");
+	}
+
+	class Tab6 : ContentPage
+	{
+		Label _onNavigatedToCountLabel;
+		Label _onAppearingCountLabel;
+		int _onNavigatedToCount;
+		int _onAppearingCount;
+
+		public Tab6()
+		{
+			_onNavigatedToCountLabel = new Label { AutomationId = "OnNavigatedToCountLabel", Text = $"OnNavigatedTo: {_onNavigatedToCount}" };
+			_onAppearingCountLabel = new Label { AutomationId = "OnAppearingCountLabel", Text = $"OnAppearing: {_onAppearingCount}" };
+			Content = new StackLayout
+			{
+				Children =
+					{
+						_onNavigatedToCountLabel,
+						_onAppearingCountLabel,
+						new Button
+						{
+							AutomationId = "button",
+							Text = "Tap to navigate to a detail page",
+							Command = new Command(() => Shell.Current.GoToAsync(nameof(Tab6DetailPage)))
+						}
+					}
+			};
+		}
+
+		protected override void OnNavigatedTo(NavigatedToEventArgs e)
+		{
+			_onNavigatedToCount++;
+			_onNavigatedToCountLabel.Text = $"OnNavigatedTo: {_onNavigatedToCount}";
+		}
+
+		protected override void OnAppearing()
+		{
+			_onAppearingCount++;
+			_onAppearingCountLabel.Text = $"OnAppearing: {_onAppearingCount}";
+		}
+	}
+
+
+	class Tab6DetailPage : ContentPage
+	{
+		public Tab6DetailPage()
+		{
+			Shell.SetBackButtonBehavior(this, new BackButtonBehavior
+			{
+				TextOverride = "Go Back",
+				Command = new Command(() => Shell.Current.GoToAsync(".."))
+			});
+		}
+	}
+}
+#endif

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue27799.cs

@@ -0,0 +1,37 @@
+#if IOS // Navigation from the more page is iOS specific
+using NUnit.Framework;
+using NUnit.Framework.Legacy;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue27799 : _IssuesUITest
+	{
+		public Issue27799(TestDevice testDevice) : base(testDevice)
+		{
+		}
+
+		public override string Issue => "[iOS] OnAppearing and OnNavigatedTo does not work when using extended Tabbar";
+
+[Test]
+[Category(UITestCategories.Shell)]
+public void OnAppearingAndOnNavigatedToShouldBeCalled()
+		{
+			App.WaitForElement("More");
+			App.Click("More");
+			App.WaitForElement("Tab6");
+			App.Click("Tab6");
+			App.WaitForElement("GoToSubpage6Button");
+			App.Click("GoToSubpage6Button");
+			App.Click("tab2");
+			App.WaitForElement("OnNavigatedToCountLabel");
+			var onNavigatedToCountLabel = App.FindElement("OnNavigatedToCountLabel").GetText();
+			var onAppearingCountLabel = App.FindElement("OnAppearingCountLabel").GetText();
+
+			ClassicAssert.AreEqual("OnNavigatedTo: 3", onNavigatedToCountLabel);
+			ClassicAssert.AreEqual("OnAppearing: 3", onAppearingCountLabel);
+		}
+	}
+}
+#endif

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue27800.cs

@@ -0,0 +1,38 @@
+#if IOS // Navigation from the more page is iOS specific
+using NUnit.Framework;
+using NUnit.Framework.Legacy;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue27800 : _IssuesUITest
+	{
+		public Issue27800(TestDevice testDevice) : base(testDevice)
+		{
+		}
+
+		public override string Issue => "Shell.BackButtonBehavior does not work when using extended Tabbar";
+
+[Test]
+[Category(UITestCategories.Shell)]
+public void ShellBackButtonBehaviorShouldWorkWithMoreTab()
+		{
+			App.WaitForElement("More");
+			App.Click("More");
+			App.WaitForElement("tab6");
+			App.Click("tab6");
+			App.WaitForElement("button");
+			App.Click("button");
+			App.WaitForElement("Go Back");
+			App.Click("Go Back");
+			App.WaitForElement("OnNavigatedToCountLabel");
+			var onNavigatedToCountLabel = App.FindElement("OnNavigatedToCountLabel").GetText();
+			var onAppearingCountLabel = App.FindElement("OnAppearingCountLabel").GetText();
+
+			ClassicAssert.AreEqual("OnNavigatedTo: 2", onNavigatedToCountLabel);
+			ClassicAssert.AreEqual("OnAppearing: 2", onAppearingCountLabel);
+		}
+	}
+}
+#endif