[Android] Fix Loaded event not triggering when navigating back to a previous page

src/Controls/src/Core/VisualElement/VisualElement.Platform.cs

@@ -27,7 +27,23 @@ partial void HandlePlatformUnloadedLoaded()
 			{
 				if (view.IsLoaded())
 				{
+#if ANDROID
+					// On Android, during navigation, fragments can be reused which means
+					// the normal ViewAttachedToWindow events might not fire. This fixes
+					// issue #29414 where navigating back to a page doesn't trigger the Loaded event.
+					// If we have subscribers to the loaded event and the platform view is loaded,
+					// we should force the loaded event to fire.
+					if (_loaded is not null)
+					{
+						SendLoaded(false, true);
+					}
+					else
+					{
+						SendLoaded(false);
+					}
+#else
 					SendLoaded(false);
+#endif
 
 					// If SendLoaded caused the unloaded tokens to wire up
 					_loadedUnloadedToken?.Dispose();

src/Controls/src/Core/VisualElement/VisualElement.cs

@@ -2265,7 +2265,12 @@ event EventHandler? IControlsVisualElement.PlatformContainerViewChanged
 		void SendLoaded() => SendLoaded(true);
 		void SendLoaded(bool updateWiring)
 		{
-			if (_isLoadedFired)
+			SendLoaded(updateWiring, false);
+		}
+
+		void SendLoaded(bool updateWiring, bool force)
+		{
+			if (!force && _isLoadedFired)
 				return;
 
 			_isLoadedFired = true;
@@ -2295,6 +2300,15 @@ void SendUnloaded(bool updateWiring)
 				UpdatePlatformUnloadedLoadedWiring(Window);
 		}
 
+		// Internal method to force the Loaded event to fire again.
+		// This is used by platform-specific navigation code when a page becomes visible
+		// again but the normal platform lifecycle events don't fire (e.g., Android fragment reuse).
+		internal void ForceLoadedEvent()
+		{
+			// Force the loaded event to fire even if it has already fired before
+			SendLoaded(false, true);
+		}
+
 		static void OnWindowChanged(BindableObject bindable, object? oldValue, object? newValue)
 		{
 			if (bindable is not VisualElement visualElement)

src/Controls/tests/TestCases.HostApp/Issues/Issue29414.cs

@@ -0,0 +1,125 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 29414, "[Android] Loaded event not triggered when navigating back to a previous page", PlatformAffected.Android)]
+public partial class Issue29414 : ContentPage
+{
+	private int _mainPageLoadedCount = 0;
+	private Label _mainPageLoadedLabel;
+	private Label _secondPageLoadedLabel;
+
+	public Issue29414()
+	{
+		InitializeComponent();
+	}
+
+	private void InitializeComponent()
+	{
+		var layout = new StackLayout
+		{
+			Spacing = 10,
+			Padding = 20
+		};
+
+		var titleLabel = new Label
+		{
+			Text = "Main Page - Loaded Event Test",
+			FontSize = 18,
+			FontAttributes = FontAttributes.Bold,
+			AutomationId = "MainPageTitle"
+		};
+
+		_mainPageLoadedLabel = new Label
+		{
+			Text = "Main Page Loaded Count: 0",
+			AutomationId = "MainPageLoadedCount"
+		};
+
+		var navigateButton = new Button
+		{
+			Text = "Navigate to Second Page",
+			AutomationId = "NavigateToSecondPageButton"
+		};
+		navigateButton.Clicked += OnNavigateToSecondPageClicked;
+
+		layout.Children.Add(titleLabel);
+		layout.Children.Add(_mainPageLoadedLabel);
+		layout.Children.Add(navigateButton);
+
+		Content = layout;
+
+		// Subscribe to the Loaded event
+		Loaded += OnMainPageLoaded;
+	}
+
+	private void OnMainPageLoaded(object sender, EventArgs e)
+	{
+		_mainPageLoadedCount++;
+		_mainPageLoadedLabel.Text = $"Main Page Loaded Count: {_mainPageLoadedCount}";
+	}
+
+	private async void OnNavigateToSecondPageClicked(object sender, EventArgs e)
+	{
+		await Navigation.PushAsync(new SecondPage());
+	}
+}
+
+public partial class SecondPage : ContentPage
+{
+	private int _secondPageLoadedCount = 0;
+	private Label _secondPageLoadedLabel;
+
+	public SecondPage()
+	{
+		InitializeComponent();
+	}
+
+	private void InitializeComponent()
+	{
+		var layout = new StackLayout
+		{
+			Spacing = 10,
+			Padding = 20
+		};
+
+		var titleLabel = new Label
+		{
+			Text = "Second Page",
+			FontSize = 18,
+			FontAttributes = FontAttributes.Bold,
+			AutomationId = "SecondPageTitle"
+		};
+
+		_secondPageLoadedLabel = new Label
+		{
+			Text = "Second Page Loaded Count: 0",
+			AutomationId = "SecondPageLoadedCount"
+		};
+
+		var navigateBackButton = new Button
+		{
+			Text = "Navigate Back to Main Page",
+			AutomationId = "NavigateBackToMainPageButton"
+		};
+		navigateBackButton.Clicked += OnNavigateBackClicked;
+
+		layout.Children.Add(titleLabel);
+		layout.Children.Add(_secondPageLoadedLabel);
+		layout.Children.Add(navigateBackButton);
+
+		Content = layout;
+
+		// Subscribe to the Loaded event
+		Loaded += OnSecondPageLoaded;
+	}
+
+	private void OnSecondPageLoaded(object sender, EventArgs e)
+	{
+		_secondPageLoadedCount++;
+		_secondPageLoadedLabel.Text = $"Second Page Loaded Count: {_secondPageLoadedCount}";
+	}
+
+	private async void OnNavigateBackClicked(object sender, EventArgs e)
+	{
+		await Navigation.PopAsync();
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue29414.cs

@@ -0,0 +1,80 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues
+{
+	public class Issue29414 : _IssuesUITest
+	{
+		public Issue29414(TestDevice testDevice) : base(testDevice)
+		{
+		}
+
+		public override string Issue => "[Android] Loaded event not triggered when navigating back to a previous page";
+
+		[Test]
+		[Category(UITestCategories.Page)]
+		[Category(UITestCategories.Navigation)]
+		public void LoadedEventShouldFireWhenNavigatingBackToPage()
+		{
+			// Step 1: Verify the main page loaded event fired initially
+			App.WaitForElement("MainPageLoadedCount");
+			var initialLoadedText = App.FindElement("MainPageLoadedCount").GetText();
+			Assert.That(initialLoadedText, Is.EqualTo("Main Page Loaded Count: 1"), 
+				"Main page should have loaded count of 1 initially");
+
+			// Step 2: Navigate to second page
+			App.WaitForElement("NavigateToSecondPageButton");
+			App.Tap("NavigateToSecondPageButton");
+
+			// Step 3: Verify second page loads
+			App.WaitForElement("SecondPageLoadedCount");
+			var secondPageLoadedText = App.FindElement("SecondPageLoadedCount").GetText();
+			Assert.That(secondPageLoadedText, Is.EqualTo("Second Page Loaded Count: 1"), 
+				"Second page should have loaded count of 1");
+
+			// Step 4: Navigate back to main page
+			App.WaitForElement("NavigateBackToMainPageButton");
+			App.Tap("NavigateBackToMainPageButton");
+
+			// Step 5: Verify main page loaded event fired again (this is the failing test case)
+			App.WaitForElement("MainPageLoadedCount");
+			var finalLoadedText = App.FindElement("MainPageLoadedCount").GetText();
+			Assert.That(finalLoadedText, Is.EqualTo("Main Page Loaded Count: 2"), 
+				"Main page should have loaded count of 2 after navigating back - THIS IS THE BUG ON ANDROID");
+		}
+
+		[Test]
+		[Category(UITestCategories.Page)]
+		[Category(UITestCategories.Navigation)]
+		public void LoadedEventShouldFireMultipleTimesWhenNavigatingBackAndForth()
+		{
+			// Navigate back and forth multiple times to ensure loaded events keep firing
+			App.WaitForElement("MainPageLoadedCount");
+
+			// Initial state
+			var mainPageText = App.FindElement("MainPageLoadedCount").GetText();
+			Assert.That(mainPageText, Is.EqualTo("Main Page Loaded Count: 1"));
+
+			// Navigate to second page and back - first time
+			App.Tap("NavigateToSecondPageButton");
+			App.WaitForElement("NavigateBackToMainPageButton");
+			App.Tap("NavigateBackToMainPageButton");
+
+			App.WaitForElement("MainPageLoadedCount");
+			mainPageText = App.FindElement("MainPageLoadedCount").GetText();
+			Assert.That(mainPageText, Is.EqualTo("Main Page Loaded Count: 2"), 
+				"Main page should have loaded count of 2 after first back navigation");
+
+			// Navigate to second page and back - second time
+			App.Tap("NavigateToSecondPageButton");
+			App.WaitForElement("NavigateBackToMainPageButton");
+			App.Tap("NavigateBackToMainPageButton");
+
+			App.WaitForElement("MainPageLoadedCount");
+			mainPageText = App.FindElement("MainPageLoadedCount").GetText();
+			Assert.That(mainPageText, Is.EqualTo("Main Page Loaded Count: 3"), 
+				"Main page should have loaded count of 3 after second back navigation");
+		}
+	}
+}