- add interface to WrapperView and move to ext method

Author: PureWeen

src/Core/src/Platform/iOS/MauiScrollView.cs

@@ -44,7 +44,7 @@ public override void LayoutSubviews()
 				// imposed by the parent (i.e. scroll view) with the current bounds.
 				// But we _do_ need LayoutSubviews to make a measurement pass if the parent is something else (for example,
 				// the window); there's no guarantee that SizeThatFits has been called in that case.
-				if (!IsMeasureValid(widthConstraint, heightConstraint) && Superview is not ICrossPlatformLayoutBacking)
+				if (!IsMeasureValid(widthConstraint, heightConstraint) && !this.IsFinalMeasureHandledBySuperView())
 				{
 					crossPlatformLayout.CrossPlatformMeasure(widthConstraint, heightConstraint);
 					CacheMeasureConstraints(widthConstraint, heightConstraint);

src/Core/src/Platform/iOS/MauiView.cs

@@ -131,7 +131,7 @@ public override void LayoutSubviews()
 			// imposed by the parent (i.e. scroll view) with the current bounds.
 			// But we _do_ need LayoutSubviews to make a measurement pass if the parent is something else (for example,
 			// the window); there's no guarantee that SizeThatFits has been called in that case.
-			if (!IsMeasureValid(widthConstraint, heightConstraint) && Superview is not ICrossPlatformLayoutBacking)
+			if (!IsMeasureValid(widthConstraint, heightConstraint) && !this.IsFinalMeasureHandledBySuperView())
 			{
 				CrossPlatformMeasure(widthConstraint, heightConstraint);
 				CacheMeasureConstraints(widthConstraint, heightConstraint);

src/Core/src/Platform/iOS/ViewExtensions.cs

@@ -945,5 +945,7 @@ internal static float GetDisplayDensity(this UIView? view) =>
 		internal static bool ShowSoftInput(this UIView inputView) => inputView.BecomeFirstResponder();
 
 		internal static bool IsSoftInputShowing(this UIView inputView) => inputView.IsFirstResponder;
+
+		internal static bool IsFinalMeasureHandledBySuperView(this UIView? view) => view?.Superview is ICrossPlatformLayoutBacking { CrossPlatformLayout: not null };
 	}
 }

src/Core/src/Platform/iOS/WrapperView.cs

@@ -9,16 +9,22 @@
 
 namespace Microsoft.Maui.Platform
 {
-	public partial class WrapperView : UIView, IDisposable, IUIViewLifeCycleEvents
+	public partial class WrapperView : UIView, IDisposable, IUIViewLifeCycleEvents, ICrossPlatformLayoutBacking
 	{
 		bool _fireSetNeedsLayoutOnParentWhenWindowAttached;
 		WeakReference<ICrossPlatformLayout>? _crossPlatformLayoutReference;
 
-		internal ICrossPlatformLayout? CrossPlatformLayout
+		ICrossPlatformLayout? ICrossPlatformLayoutBacking.CrossPlatformLayout
 		{
 			get => _crossPlatformLayoutReference != null && _crossPlatformLayoutReference.TryGetTarget(out var v) ? v : null;
 			set => _crossPlatformLayoutReference = value == null ? null : new WeakReference<ICrossPlatformLayout>(value);
 		}
+		
+		internal ICrossPlatformLayout? CrossPlatformLayout
+		{
+			get => ((ICrossPlatformLayoutBacking)this).CrossPlatformLayout;
+			set => ((ICrossPlatformLayoutBacking)this).CrossPlatformLayout = value;
+		}
 
 		double _lastMeasureHeight = double.NaN;
 		double _lastMeasureWidth = double.NaN;