[Android, Windows] Fix for FlyoutPage toolbar button not updating on orientation change

src/Controls/src/Core/FlyoutPage/FlyoutPage.cs

@@ -351,6 +351,12 @@ void OnWindowChanged(object sender, EventArgs e)
 		void OnMainDisplayInfoChanged(object sender, DisplayInfoChangedEventArgs e)
 		{
 			Handler?.UpdateValue(nameof(FlyoutBehavior));
+
+#if ANDROID || WINDOWS
+			// Trigger toolbar re-evaluation on orientation change. iOS handles this natively
+			// via PhoneFlyoutPageRenderer.ViewWillTransitionToSize().
+			OnPropertyChanged(nameof(FlyoutLayoutBehavior));
+#endif
 		}
 
 		IView IFlyoutView.Flyout => this.Flyout;

src/Controls/src/Core/NavigationPage/NavigationPageToolbar.cs

@@ -55,7 +55,8 @@ void OnPagePropertyChanged(object sender, System.ComponentModel.PropertyChangedE
 				NavigationPage.BarTextColorProperty) ||
 				e.IsOneOf(
 					PlatformConfiguration.WindowsSpecific.Page.ToolbarDynamicOverflowEnabledProperty,
-					PlatformConfiguration.WindowsSpecific.Page.ToolbarPlacementProperty))
+					PlatformConfiguration.WindowsSpecific.Page.ToolbarPlacementProperty) ||
+				e.Is(FlyoutPage.FlyoutLayoutBehaviorProperty))
 			{
 				ApplyChanges(_currentNavigationPage);
 			}

src/Controls/tests/TestCases.HostApp/Issues/Issue24468.cs

@@ -0,0 +1,64 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 24468, "FlyoutPage toolbar button not updating on orientation change on Android and Windows", 
+    PlatformAffected.Android | PlatformAffected.UWP)]
+public class Issue24468 : TestFlyoutPage
+{
+    private Label _eventLabel;
+    private Label _countLabel;
+    private int _callCount = 0;
+
+    protected override void Init()
+    {
+        Title = "Issue 24468";
+
+        _eventLabel = new Label 
+        { 
+            Text = "ShouldShowToolbarButton is not called",
+            AutomationId = "EventLabel"
+        };
+
+        _countLabel = new Label 
+        { 
+            Text = "0",
+            AutomationId = "CountLabel"
+        };
+
+        Flyout = new ContentPage
+        {
+            Title = "Menu",
+            Content = new Label { Text = "Flyout Menu" }
+        };
+
+        Detail = new NavigationPage(new ContentPage
+        {
+            Title = "Detail",
+            Content = new StackLayout
+            {
+                Children =
+                {
+                    new Label { Text = "Rotate device to test toolbar button updates" },
+                    _eventLabel,
+                    _countLabel
+                }
+            }, 
+            AutomationId = "ContentPage"
+        });
+
+        FlyoutLayoutBehavior = FlyoutLayoutBehavior.SplitOnLandscape;
+    }
+
+    public override bool ShouldShowToolbarButton()
+    {
+        _callCount++;
+        var shouldShow = base.ShouldShowToolbarButton();
+
+        if (_callCount > 1)
+        {
+            _eventLabel.Text = "ShouldShowToolbarButton called";
+            _countLabel.Text = _callCount.ToString();
+        }
+
+        return shouldShow;
+    }
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue24468.cs

@@ -0,0 +1,37 @@
+#if ANDROID || IOS //The test fails on Windows and MacCatalyst because the SetOrientation method, which is intended to change the device orientation, is only supported on mobile platforms iOS and Android.
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+public class Issue24468 : _IssuesUITest
+{
+    public Issue24468(TestDevice device) : base(device)
+    {
+    }
+
+    public override string Issue => "FlyoutPage toolbar button not updating on orientation change on Android and Windows";
+    [Test]
+    [Category(UITestCategories.Navigation)]
+    public void FlyoutPageToolbarButtonUpdatesOnOrientationChange()
+    {
+        App.SetOrientationLandscape();
+        App.WaitForElement("ContentPage");
+
+        try
+        {
+            App.WaitForElement("EventLabel");
+            var eventText = App.FindElement("EventLabel").GetText();
+            Assert.That(eventText, Is.EqualTo("ShouldShowToolbarButton called"));
+
+            var callCount = int.Parse(App.FindElement("CountLabel").GetText() ?? "0");
+            Assert.That(callCount, Is.GreaterThan(1).And.LessThan(5), 
+                $"Expected call count between 2-4, but got {callCount}. Method should not be called excessively.");
+        }
+        finally
+        {
+            App.SetOrientationPortrait();
+        }
+    }
+}
+#endif