[Android] Fix SearchHandler displays both Expanded and Collapsible views when SearchBoxVisibility changes at runtime

src/Controls/src/Core/Compatibility/Handlers/Shell/Android/ShellToolbarTracker.cs

@@ -644,10 +644,10 @@ protected virtual void UpdateToolbarItems(AToolbar toolbar, Page page)
 		{
 			var menu = toolbar.Menu;
 			SearchHandler = Shell.GetSearchHandler(page);
-			if (SearchHandler != null && SearchHandler.SearchBoxVisibility != SearchBoxVisibility.Hidden)
+			if (SearchHandler is not null && SearchHandler.SearchBoxVisibility != SearchBoxVisibility.Hidden)
 			{
 				var context = ShellContext.AndroidContext;
-				if (_searchView == null)
+				if (_searchView is null)
 				{
 					_searchView = GetSearchView(context);
 					_searchView.SearchHandler = SearchHandler;
@@ -673,21 +673,31 @@ protected virtual void UpdateToolbarItems(AToolbar toolbar, Page page)
 						icon.SetColorFilter(TintColor.ToPlatform(Colors.White), FilterMode.SrcAtop);
 					item.SetShowAsAction(ShowAsAction.IfRoom | ShowAsAction.CollapseActionView);
 
-					if (_searchView.View.Parent != null)
+					if (_searchView.View.Parent is not null)
+					{
 						_searchView.View.RemoveFromParent();
+					}
 
 					item.SetActionView(_searchView.View);
 					item.Dispose();
 				}
 				else if (SearchHandler.SearchBoxVisibility == SearchBoxVisibility.Expanded)
 				{
+					// Remove the placeholder menu item, if it exists, added for collapsible mode.
+					if (menu.FindItem(_placeholderMenuItemId) is not null)
+					{
+						menu.RemoveItem(_placeholderMenuItemId);
+					}
+
 					if (_searchView.View.Parent != _platformToolbar)
+					{
 						_platformToolbar.AddView(_searchView.View);
+					}
 				}
 			}
 			else
 			{
-				if (_searchView != null)
+				if (_searchView is not null)
 				{
 					_searchView.View.RemoveFromParent();
 					_searchView.View.ViewAttachedToWindow -= OnSearchViewAttachedToWindow;

src/Controls/tests/TestCases.HostApp/Issues/Issue33772.cs

@@ -0,0 +1,83 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 33772, "Shell SearchHandler SearchBoxVisibility does not update when changed dynamically", PlatformAffected.Android)]
+public class Issue33772 : Shell
+{
+	readonly SearchHandler _searchHandler;
+	readonly Label _statusLabel;
+
+	public Issue33772()
+	{
+		_searchHandler = new SearchHandler
+		{
+			Placeholder = "Search here...",
+			AutomationId = "SearchHandler",
+			SearchBoxVisibility = SearchBoxVisibility.Collapsible
+		};
+
+		_statusLabel = new Label
+		{
+			Text = "Current: Collapsible",
+			FontSize = 18,
+			HorizontalOptions = LayoutOptions.Center,
+			AutomationId = "StatusLabel"
+		};
+
+		var expandButton = new Button
+		{
+			Text = "Change to Expanded",
+			AutomationId = "ExpandButton",
+			HorizontalOptions = LayoutOptions.Center
+		};
+
+		expandButton.Clicked += OnExpandedClicked;
+
+		var collapsibleButton = new Button
+		{
+			Text = "Change to Collapsible",
+			AutomationId = "CollapsibleButton",
+			HorizontalOptions = LayoutOptions.Center
+		};
+
+		collapsibleButton.Clicked += OnCollapsibleClicked;
+
+		var contentPage = new ContentPage
+		{
+			Title = "SearchHandler Visibility Test",
+			Content = new VerticalStackLayout
+			{
+				Padding = 10,
+				Spacing = 25,
+				Children =
+				{
+					new Label
+					{
+						Text = "SearchHandler SearchBoxVisibility Test",
+						FontSize = 18,
+						HorizontalOptions = LayoutOptions.Center,
+						AutomationId = "TitleLabel"
+					},
+					expandButton,
+					collapsibleButton,
+					_statusLabel
+				}
+			}
+		};
+
+		SetSearchHandler(contentPage, _searchHandler);
+
+		Items.Add(new ShellContent { Content = contentPage });
+	}
+
+	void OnExpandedClicked(object sender, EventArgs e)
+	{
+		_searchHandler.SearchBoxVisibility = SearchBoxVisibility.Expanded;
+		_statusLabel.Text = "Current: Expanded";
+	}
+
+	void OnCollapsibleClicked(object sender, EventArgs e)
+	{
+		_searchHandler.SearchBoxVisibility = SearchBoxVisibility.Collapsible;
+		_statusLabel.Text = "Current: Collapsible";
+	}
+}

src/Controls/tests/TestCases.Shared.Tests/Tests/Issues/Issue33772.cs

@@ -0,0 +1,31 @@
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue33772 : _IssuesUITest
+{
+    public Issue33772(TestDevice testDevice) : base(testDevice) { }
+
+    public override string Issue => "Shell SearchHandler SearchBoxVisibility does not update when changed dynamically";
+
+    [Test, Order(1)]
+    [Category(UITestCategories.Shell)]
+    public void SearchHandlerVisibilityChangesToExpanded()
+    {
+        App.WaitForElement("TitleLabel");
+        App.Tap("ExpandButton");
+        VerifyScreenshot();
+    }
+
+    [Test, Order(2)]
+    [Category(UITestCategories.Shell)]
+    public void SearchHandlerVisibilityChangesToCollapsible()
+    {
+        // Wait for the page to load
+        App.WaitForElement("TitleLabel");
+        App.Tap("CollapsibleButton");
+        VerifyScreenshot();
+    }
+}