[iOS] Fixed Shell.SearchHandler ClearPlaceholderIcon Color Issue (#28601)

* SearchHandler ClearPlaceholderIcon color fix

* Added Mac snapshot

* Updated SearchBar Icon changes

* Test script changes.

* Revert unwanted changes

* Updated custom icon changes

Author: Tamilarasan-Paranthaman

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

@@ -807,7 +807,14 @@ void SearchButtonClicked(object sender, EventArgs e)
 
 		void SetSearchBarIcon(UISearchBar searchBar, ImageSource source, UISearchBarIcon icon)
 		{
-			source.LoadImage(source.FindMauiContext(), image =>
+			var mauiContext = source.FindMauiContext(true);
+
+			if (mauiContext is null)
+			{
+				return;
+			}
+
+			source.LoadImage(mauiContext, image =>
 			{
 				var result = image?.Value;
 				if (result != null)
@@ -833,6 +840,11 @@ void OnPageLoaded(object sender, EventArgs e)
 			}
 
 			UpdateToolbarItemsInternal();
+
+			//UIKIt will try to override our colors when the SearchController is inside the NavigationBar
+			//Best way was to force them to be set again when page is loaded / ViewDidLoad
+			_searchHandlerAppearanceTracker?.UpdateSearchBarColors();
+
 			CheckAppeared();
 		}
 
@@ -854,9 +866,6 @@ void SetAppeared()
 				return;
 
 			_isVisiblePage = true;
-			//UIKIt will try to override our colors when the SearchController is inside the NavigationBar
-			//Best way was to force them to be set again when page is Appearing / ViewDidLoad
-			_searchHandlerAppearanceTracker?.UpdateSearchBarColors();
 			UpdateShellToMyPage();
 
 			if (_context.Shell.Toolbar != null)

src/Controls/tests/TestCases.Android.Tests/snapshots/android/VerifySearchHandlerClearPlaceholderIconColor.png

@@ -0,0 +1,46 @@
+namespace Maui.Controls.Sample.Issues;
+
+[Issue(IssueTracker.Github, 20250, "[iOS] SearchHandler ClearPlaceholderIcon color", PlatformAffected.iOS)]
+public partial class Issue20250 : TestShell
+{
+
+	protected override void Init()
+	{
+		this.FlyoutBehavior = FlyoutBehavior.Flyout;
+
+		var shellContent = new ShellContent
+		{
+			Title = "Home",
+			Route = "MainPage",
+			Content = new Issue20250ContentPage() { Title = "Home" }
+		};
+
+		Items.Add(shellContent);
+
+	}
+	class Issue20250ContentPage : ContentPage
+	{
+		public Issue20250ContentPage()
+		{
+			Shell.SetSearchHandler(this, new SearchHandler
+			{
+				AutomationId = "searchHandler",
+				Placeholder = "Search",
+				TextColor = Colors.Red,
+				ClearPlaceholderEnabled = true,
+				ClearPlaceholderIcon = "bank.png",
+
+			});
+
+			this.SetBinding(TitleProperty, new Binding("Title", source: Shell.Current));
+
+			Content = new Label
+			{
+				Text = "SearchHandler",
+				AutomationId = "label",
+				HorizontalOptions = LayoutOptions.Center,
+				VerticalOptions = LayoutOptions.Center,
+			};
+		}
+	}
+}

src/Controls/tests/TestCases.HostApp/Issues/Issue20250.cs

@@ -0,0 +1,26 @@
+#if TEST_FAILS_ON_WINDOWS // On Windows, the ClearPlaceholderIcon is not displayed in the SearchHandler.
+// Issue: https://github.com/dotnet/maui/issues/28619
+using NUnit.Framework;
+using UITest.Appium;
+using UITest.Core;
+
+namespace Microsoft.Maui.TestCases.Tests.Issues;
+
+public class Issue20250 : _IssuesUITest
+{
+	public override string Issue => "[iOS] SearchHandler ClearPlaceholderIcon color";
+
+	public Issue20250(TestDevice device)
+	: base(device)
+	{ }
+
+	[Test]
+	[Category(UITestCategories.Shell)]
+	public void VerifySearchHandlerClearPlaceholderIconColor()
+	{
+		App.WaitForElement("label");
+		VerifyScreenshot();
+	}
+}
+
+#endif