[IOS] - Fix error when running new template maui app on iOS

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

@@ -345,7 +345,7 @@ void UpdateMoreCellsEnabled()
 
 			UITableViewCell[] GetMoreNavigationCells()
 			{
-				if (MoreNavigationController.TopViewController.View is UITableView uITableView)
+				if (MoreNavigationController.TopViewController.View is UITableView uITableView && uITableView.Window is not null)
 					return uITableView.VisibleCells;
 
 				return EmptyUITableViewCellArray;

src/Controls/tests/TestCases.HostApp/Issues/Issue22452.xaml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<Shell xmlns="http://schemas.microsoft.com/dotnet/2021/maui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+    x:Class="Maui.Controls.Sample.Issues.Issue22452"
+    xmlns:ns="clr-namespace:Maui.Controls.Sample.Issues"
+    Shell.FlyoutBehavior="Locked">
+
+  <FlyoutItem Title="FlyoutItem">
+    <Tab>
+      <ShellContent ContentTemplate="{DataTemplate ns:Issue22452Content}" />
+    </Tab>
+  </FlyoutItem>
+</Shell>

src/Controls/tests/TestCases.HostApp/Issues/Issue22452.xaml.cs

@@ -0,0 +1,32 @@
+namespace Maui.Controls.Sample.Issues
+{
+	[XamlCompilation(XamlCompilationOptions.Compile)]
+	[Issue(IssueTracker.Github, 22452, "Fix error when running new template maui app on iOS", PlatformAffected.iOS)]
+	public partial class Issue22452 : Shell
+	{
+		public Issue22452()
+		{
+			InitializeComponent();
+		}
+	}
+
+	public class Issue22452Content : ContentPage
+	{
+		public Issue22452Content()
+		{
+			Content = new StackLayout
+			{
+				Children =
+				{
+					new Label
+					{
+						AutomationId="TabContent",
+						Text = "TabContent"
+					}
+				},
+
+				IgnoreSafeArea = false
+			};
+		}
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue22452.cs

@@ -0,0 +1,21 @@
+using System.Diagnostics;
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue22452 : _IssuesUITest
+{
+	public Issue22452(TestDevice device) : base(device) { }
+
+	public override string Issue => "Fix error when running new template maui app on iOS";
+
+	[Test]
+	[Category(UITestCategories.Shell)]
+	public void NavigationBetweenFlyoutItems()
+	{
+		App.WaitForElement("TabContent");
+		VerifyScreenshot();
+	}
+}