[iOS] Fix SearchBar.CancelButtonColor not applied on iOS 26

src/Core/src/Platform/iOS/SearchBarExtensions.cs

@@ -1,4 +1,5 @@
 using System;
+using CoreGraphics;
 using Foundation;
 using Microsoft.Maui.Graphics;
 using UIKit;
@@ -119,26 +120,193 @@ public static void UpdateIsReadOnly(this UISearchBar uiSearchBar, ISearchBar sea
 		internal static bool ShouldShowCancelButton(this ISearchBar searchBar) =>
 			!string.IsNullOrEmpty(searchBar.Text);
 
+		// Tag used to identify the cancel button color overlay view added on iOS 26+.
+		// Value 0x53424343 encodes "SBCC" (SearchBarCancelColor) to avoid collisions with system-assigned tags.
+		const nint CancelButtonColorOverlayTag = unchecked((nint)0x53424343);
+
 		public static void UpdateCancelButton(this UISearchBar uiSearchBar, ISearchBar searchBar)
 		{
 			uiSearchBar.ShowsCancelButton = searchBar.ShouldShowCancelButton();
 
 			// We can't cache the cancel button reference because iOS drops it when it's not displayed
-			// and creates a brand new one when necessary, so we have to look for it each time
-			var cancelButton = uiSearchBar.FindDescendantView<UIButton>();
+			// and creates a brand new one when necessary, so we have to look for it each time.
+			// Exclude UIButton instances that are descendants of UITextField — those are the
+			// text-clear button inside the search field, not the cancel button outside it.
+			var cancelButton = uiSearchBar.FindDescendantView<UIButton>(
+				btn => btn.FindParent(v => v is UITextField) == null);
 
 			if (cancelButton == null)
+			{
+				// Cancel button is hidden — remove any overlay we previously added
+				if (OperatingSystem.IsIOSVersionAtLeast(26))
+					RemoveCancelButtonOverlay(uiSearchBar);
 				return;
+			}
 
 			if (searchBar.CancelButtonColor != null)
 			{
-				cancelButton.SetTitleColor(searchBar.CancelButtonColor.ToPlatform(), UIControlState.Normal);
-				cancelButton.SetTitleColor(searchBar.CancelButtonColor.ToPlatform(), UIControlState.Highlighted);
-				cancelButton.SetTitleColor(searchBar.CancelButtonColor.ToPlatform(), UIControlState.Disabled);
+				var platformColor = searchBar.CancelButtonColor.ToPlatform();
 
+				cancelButton.SetTitleColor(platformColor, UIControlState.Normal);
+				cancelButton.SetTitleColor(platformColor, UIControlState.Highlighted);
+				cancelButton.SetTitleColor(platformColor, UIControlState.Disabled);
+
+				// On Mac, the cancel button is rendered as an icon (X mark) rather than text,
+				// so TintColor must be used to apply the color to the icon.
 				if (cancelButton.TraitCollection.UserInterfaceIdiom == UIUserInterfaceIdiom.Mac)
-					cancelButton.TintColor = searchBar.CancelButtonColor.ToPlatform();
+				{
+					cancelButton.TintColor = platformColor;
+				}
+
+				// On iOS 26+, UIKit overrides TintColor/UIButtonConfiguration on every layout
+				// pass, making standard color APIs ineffective for the cancel button icon.
+				// Place a colored UIImageView sibling on top of the cancel button to apply
+				// the color outside UIButton's rendering pipeline.
+				// Defer via DispatchAsync so the cancel button frame is valid after layout.
+				// Capture the search bar (not the button) to always look up the current
+				// cancel button instance — iOS 26 may recreate it during theme transitions.
+				if (OperatingSystem.IsIOSVersionAtLeast(26))
+				{
+					var weakSearchBar = new WeakReference<UISearchBar>(uiSearchBar);
+					var weakVirtualView = new WeakReference<ISearchBar>(searchBar);
+					CoreFoundation.DispatchQueue.MainQueue.DispatchAsync(() =>
+					{
+						if (!weakSearchBar.TryGetTarget(out var sb))
+						{
+							return;
+						}
+
+						if (!weakVirtualView.TryGetTarget(out var virtualSearchBar))
+						{
+							return;
+						}
+
+						// Re-evaluate the desired cancel button color; it may have been
+						// changed or cleared since this callback was queued.
+						var currentColor = virtualSearchBar.CancelButtonColor;
+						if (currentColor is null)
+						{
+							RemoveCancelButtonOverlay(sb);
+							return;
+						}
+
+						var currentButton = sb.FindDescendantView<UIButton>(
+							btn => btn.FindParent(v => v is UITextField) == null);
+						if (currentButton is not null)
+						{
+							ApplyCancelButtonOverlay(sb, currentButton, currentColor.ToPlatform());
+						}
+					});
+				}
+			}
+			else if (OperatingSystem.IsIOSVersionAtLeast(26))
+			{
+				// CancelButtonColor was cleared — remove any overlay we previously added
+				RemoveCancelButtonOverlay(uiSearchBar);
+			}
+		}
+
+		// Schedules a deferred retry of ApplyCancelButtonOverlay on the main queue.
+		// Used when the cancel button is not ready for layout (detached or zero-frame).
+		static void ScheduleOverlayRetry(UISearchBar uiSearchBar, UIColor color, int retryCount)
+		{
+			var weakSB = new WeakReference<UISearchBar>(uiSearchBar);
+			CoreFoundation.DispatchQueue.MainQueue.DispatchAsync(() =>
+			{
+				if (!weakSB.TryGetTarget(out var sb)) return;
+				var btn = sb.FindDescendantView<UIButton>(
+					b => b.FindParent(v => v is UITextField) == null);
+				if (btn != null)
+					ApplyCancelButtonOverlay(sb, btn, color, retryCount + 1);
+			});
+		}
+
+		static void ApplyCancelButtonOverlay(UISearchBar uiSearchBar, UIButton cancelButton, UIColor color, int retryCount = 0)
+		{
+			var parentView = cancelButton.Superview;
+			if (parentView == null)
+			{
+				// Button was detached by UIKit (e.g. mid-transition during a theme change).
+				// Retry with a fresh lookup so we always work with the current button instance.
+				if (retryCount < 2)
+					ScheduleOverlayRetry(uiSearchBar, color, retryCount);
+				return;
+			}
+
+			// Remove any overlay from a previous call (e.g. color change or re-focus)
+			uiSearchBar.ViewWithTag(CancelButtonColorOverlayTag)?.RemoveFromSuperview();
+
+			// Find the UIImageView that UIButton uses to render the X icon.
+			// We need its frame to determine the rendered image size.
+			var iv = cancelButton.FindDescendantView<UIImageView>();
+			if (iv == null)
+				return;
+
+			// Convert the icon's frame from its local coordinate space to the parent view.
+			var iconFrameInParent = parentView.ConvertRectFromView(iv.Frame, iv.Superview);
+			if (iconFrameInParent.Width <= 0 || iconFrameInParent.Height <= 0)
+			{
+				// The cancel button hasn't been laid out yet (e.g. on initial load when
+				// CancelButtonColor is set via AppThemeBinding before the view appears).
+				// Retry after the next layout pass (up to two times) so we get a valid frame.
+				if (retryCount < 2)
+					ScheduleOverlayRetry(uiSearchBar, color, retryCount);
+				return;
 			}
+
+			// Render the xmark icon in the requested color using CoreGraphics.
+			// AlwaysOriginal prevents UIKit from re-tinting the baked image.
+			var xmarkImage = UIImage.GetSystemImage("xmark");
+			if (xmarkImage == null)
+				return;
+
+			var imageSize = iconFrameInParent.Size;
+			var renderer = new UIGraphicsImageRenderer(imageSize, new UIGraphicsImageRendererFormat
+			{
+				Opaque = false,
+				Scale = 0,
+			});
+
+			var coloredImage = renderer.CreateImage(_ =>
+			{
+				xmarkImage.Draw(new CGRect(CGPoint.Empty, imageSize));
+				var ctx = UIGraphics.GetCurrentContext();
+				if (ctx != null)
+				{
+					ctx.SetBlendMode(CGBlendMode.SourceIn);
+					ctx.SetFillColor(color.CGColor);
+					ctx.FillRect(new CGRect(CGPoint.Empty, imageSize));
+				}
+			}).ImageWithRenderingMode(UIImageRenderingMode.AlwaysOriginal);
+
+			// Add the overlay as the last (topmost) sibling of the cancel button.
+			// Use Auto Layout constraints so the overlay stays centered over the X icon
+			// on rotation, multitasking split view, or dynamic type changes.
+			var overlay = new UIImageView
+			{
+				Image = coloredImage,
+				ContentMode = UIViewContentMode.ScaleAspectFit,
+				Tag = CancelButtonColorOverlayTag,
+				UserInteractionEnabled = false,
+				TranslatesAutoresizingMaskIntoConstraints = false,
+			};
+
+			parentView.AddSubview(overlay);
+
+			NSLayoutConstraint.ActivateConstraints(new NSLayoutConstraint[]
+			{
+				overlay.CenterXAnchor.ConstraintEqualTo(cancelButton.CenterXAnchor),
+				overlay.CenterYAnchor.ConstraintEqualTo(cancelButton.CenterYAnchor),
+				overlay.WidthAnchor.ConstraintEqualTo(imageSize.Width),
+				overlay.HeightAnchor.ConstraintEqualTo(imageSize.Height),
+			});
+		}
+
+		static void RemoveCancelButtonOverlay(UISearchBar uiSearchBar)
+		{
+			// UIView.ViewWithTag searches the entire subtree recursively, so it finds the overlay
+			// regardless of where it was placed in the search bar's view hierarchy.
+			uiSearchBar.ViewWithTag(CancelButtonColorOverlayTag)?.RemoveFromSuperview();
 		}
 
 		internal static void UpdateSearchIcon(this UISearchBar uiSearchBar, ISearchBar searchBar)