[Android] Overriding back button functionality with OnBackButtonPressed returning false in a modally pushed page causes stack overflow - fix (#28812)

* Update ModalNavigationManager.Android.cs

[Android] ModalNavigationManager

* Update ModalNavigationManager.Android.cs

* Remove unused back propagation logic in Android modal manager

Eliminated the preventBackPropagation variable and related event handler code from ModalNavigationManager.Android.cs, simplifying the OnBackPressed lifecycle event handling.

Author: kubaflo

src/Controls/src/Core/Platform/ModalNavigationManager/ModalNavigationManager.Android.cs

@@ -415,45 +415,14 @@ public override void HandleOnBackPressed()
 							return;
 						}
 
-						Window? window = activity.GetWindow() as Window;
-						EventHandler? eventHandler = null;
-						eventHandler = OnPopCanceled;
-						if (window is not null)
-						{
-							window.PopCanceled += eventHandler;
-						}
-
-						var preventBackPropagation = false;
-
 						try
 						{
 							IPlatformApplication.Current?.Services?.InvokeLifecycleEvents<AndroidLifecycle.OnBackPressed>(del =>
 							{
-								preventBackPropagation = del(activity) || preventBackPropagation;
+								del(activity);
 							});
 						}
-						finally
-						{
-							if (window is not null && eventHandler is not null)
-							{
-								window.PopCanceled -= eventHandler;
-							}
-						}
-
-						if (!preventBackPropagation)
-						{
-							customComponentDialog.OnBackPressedDispatcher.OnBackPressed();
-						}
-
-						eventHandler = null;
-						void OnPopCanceled(object? sender, EventArgs e)
-						{
-							preventBackPropagation = true;
-							if (window is not null && eventHandler is not null)
-							{
-								window.PopCanceled -= eventHandler;
-							}
-						}
+						finally { }
 					}
 				}
 			}

src/Controls/tests/TestCases.HostApp/Issues/Issue28811.cs

@@ -0,0 +1,32 @@
+[Issue(IssueTracker.Github, 28811, "Overriding back button functionality with OnBackButtonPressed returning false in a modally pushed page causes stack overflow", PlatformAffected.Android)]
+public class Issue28811 : ContentPage
+{
+	public Issue28811()
+	{
+		Content = new Button()
+		{
+			AutomationId = "NavigateToDetailPage",
+			HeightRequest = 50,
+			Text = "Navigate to Detail Page",
+			Command = new Command(() => Navigation.PushModalAsync(new Issue28811DetailPage()))
+		};
+	}
+
+	class Issue28811DetailPage : ContentPage
+	{
+		public Issue28811DetailPage()
+		{
+			Content = new Label()
+			{
+				AutomationId = "Issue28811DetailPage",
+				Text = "Hello, World!",
+			};
+		}
+
+		protected override bool OnBackButtonPressed()
+		{
+			Navigation.PopModalAsync();
+			return false;
+		}
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue28811.cs

@@ -0,0 +1,27 @@
+#if ANDROID
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue28811 : _IssuesUITest
+{
+	public Issue28811(TestDevice testDevice) : base(testDevice)
+	{
+	}
+
+	public override string Issue => "Overriding back button functionality with OnBackButtonPressed returning false in a modally pushed page causes stack overflow";
+
+	[Test]
+	[Category(UITestCategories.Navigation)]
+	public void OverridingBackButtonShouldNotCauseStackOverflow()
+	{
+		App.WaitForElement("NavigateToDetailPage");
+		App.Click("NavigateToDetailPage");
+		App.WaitForElement("Issue28811DetailPage");
+		App.Back();
+		App.WaitForElement("NavigateToDetailPage");
+	}
+}
+#endif