Fix iOS Gallery (#12162)

Author: PureWeen

Stubs/Xamarin.Forms.Platform.cs

@@ -173,7 +173,9 @@ internal class _PageRenderer { }
 	internal class _FlyoutPageRenderer { }
 
 #if !__IOS__ && !TIZEN4_0
-	[RenderWith(typeof(Android.AppCompat.MasterDetailPageRenderer))]
+#pragma warning disable CS0618 // Type or member is obsolete
+	[RenderWith(typeof(MasterDetailRenderer))]
+#pragma warning restore CS0618 // Type or member is obsolete
 #elif TIZEN4_0
 #pragma warning disable CS0618 // Type or member is obsolete
 	[RenderWith (typeof(MasterDetailPageRenderer))]

Xamarin.Forms.ControlGallery.iOS/RegistrarValidationService.cs

@@ -19,10 +19,27 @@ public bool Validate(VisualElement element, out string message)
 
 			var renderer = Platform.iOS.Platform.CreateRenderer(element);
 
-			if (renderer == null 
+#pragma warning disable CS0618 // Type or member is obsolete
+			if (element is MasterDetailPage)
+			{
+				if (renderer == null
+					|| renderer.GetType().Name == "DefaultRenderer"
+					|| (Device.Idiom == TargetIdiom.Tablet && !(renderer is TabletMasterDetailRenderer))
+					|| (Device.Idiom == TargetIdiom.Phone && !(renderer is PhoneMasterDetailRenderer))
+					)
+				{
+					message = $"Failed to load proper iOS renderer for {element.GetType().Name}";
+					return false;
+				}
+
+				return true;
+			}
+#pragma warning restore CS0618 // Type or member is obsolete
+
+			if (renderer == null
 				|| renderer.GetType().Name == "DefaultRenderer"
-				|| (element is FlyoutPage && Device.Idiom == TargetIdiom.Tablet && !(renderer is TabletMasterDetailRenderer))
-				|| (element is FlyoutPage && Device.Idiom == TargetIdiom.Phone && !(renderer is PhoneMasterDetailRenderer))
+				|| (element is FlyoutPage && Device.Idiom == TargetIdiom.Tablet && !(renderer is TabletFlyoutPageRenderer))
+				|| (element is FlyoutPage && Device.Idiom == TargetIdiom.Phone && !(renderer is PhoneFlyoutPageRenderer))
 				)
 			{
 				message = $"Failed to load proper iOS renderer for {element.GetType().Name}";

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Helpers/ViewHelper.cs

@@ -43,6 +43,9 @@ public static List<Page> GetAllPages()
 		{
 			var controls = new List<Page>
 			{
+#pragma warning disable CS0618 // Type or member is obsolete
+				new MasterDetailPage { Master = new Page { Title = "Flyout" }, Detail = new Page() },
+#pragma warning restore CS0618 // Type or member is obsolete
 				new FlyoutPage { Flyout = new Page { Title = "Flyout" }, Detail = new Page() },
 				new NavigationPage(new Page()),
 				new Page(),

Xamarin.Forms.Platform.iOS/Renderers/PhoneFlyoutPageRenderer.cs

@@ -544,6 +544,9 @@ void ApplyDetailShadow(nfloat percent)
 
 	public class PhoneMasterDetailRenderer : PhoneFlyoutPageRenderer
 	{
-
+		[Preserve(Conditional = true)]
+		public PhoneMasterDetailRenderer()
+		{
+		}
 	}
 }