From 86e3e92b1cb3efafb7ae53d479f587c1cf543363 Mon Sep 17 00:00:00 2001
From: Mahmoud Ali <muddibr@gmail.com>
Date: Sun, 5 Jan 2020 09:46:29 -0400
Subject: [PATCH] Add PlatformConfiguration guard

---
 .../MasterDetailPageiOS.cs                    |  9 ++++-
 .../iOSSpecific/MasterDetailPage.cs           | 33 +++++++++++++++++++
 .../Renderers/PhoneMasterDetailRenderer.cs    | 18 ++++++++--
 3 files changed, 56 insertions(+), 4 deletions(-)
 create mode 100644 Xamarin.Forms.Core/PlatformConfiguration/iOSSpecific/MasterDetailPage.cs

diff --git a/Xamarin.Forms.Controls/GalleryPages/PlatformSpecificsGalleries/MasterDetailPageiOS.cs b/Xamarin.Forms.Controls/GalleryPages/PlatformSpecificsGalleries/MasterDetailPageiOS.cs
index 9e6b140d0de..015367ed1bf 100644
--- a/Xamarin.Forms.Controls/GalleryPages/PlatformSpecificsGalleries/MasterDetailPageiOS.cs
+++ b/Xamarin.Forms.Controls/GalleryPages/PlatformSpecificsGalleries/MasterDetailPageiOS.cs
@@ -18,7 +18,13 @@ public MasterDetailPageiOS(ICommand restore)
 				Title = "This is the detail page's Title",
 				Padding = new Thickness(0,20,0,0)
 			};
-			
+
+			void ToggleApplyShadow()
+			{
+				On<iOS>().SetApplyShadow(!On<iOS>().GetApplyShadow());
+				IsPresented = false;
+			}
+
 			var navItems = new List<NavItem>
 			{
 				new NavItem("Display Alert", "\uE171", new Command(() => DisplayAlert("Alert", "This is an alert", "OK"))),
@@ -27,6 +33,7 @@ public MasterDetailPageiOS(ICommand restore)
 				new NavItem("Audio", "\uE189", new Command(() => DisplayAlert("Audio", "Never gonna give you up...", "OK"))),
 				new NavItem("Set Detail to Navigation Page", "\uE16F", new Command(() => Detail = CreateNavigationPage())),
 				new NavItem("Set Detail to Content Page", "\uE160", new Command(() => Detail = detail)),
+				new NavItem("Toggle Apply Shadow", "\u2728", new Command(ToggleApplyShadow))
 			};
 
 			var navList = new NavList(navItems);
diff --git a/Xamarin.Forms.Core/PlatformConfiguration/iOSSpecific/MasterDetailPage.cs b/Xamarin.Forms.Core/PlatformConfiguration/iOSSpecific/MasterDetailPage.cs
new file mode 100644
index 00000000000..55718e5c1eb
--- /dev/null
+++ b/Xamarin.Forms.Core/PlatformConfiguration/iOSSpecific/MasterDetailPage.cs
@@ -0,0 +1,33 @@
+
+namespace Xamarin.Forms.PlatformConfiguration.iOSSpecific
+{
+	using FormsElement = Forms.MasterDetailPage;
+
+	public static class MasterDetailPage
+	{
+		#region ApplyShadow
+		public static readonly BindableProperty ApplyShadowProperty = BindableProperty.Create("ApplyShadow", typeof(bool), typeof(MasterDetailPage), false);
+
+		public static bool GetApplyShadow(BindableObject element)
+		{
+			return (bool)element.GetValue(ApplyShadowProperty);
+		}
+
+		public static void SetApplyShadow(BindableObject element, bool value)
+		{
+			element.SetValue(ApplyShadowProperty, value);
+		}
+
+		public static IPlatformElementConfiguration<iOS, FormsElement> SetApplyShadow(this IPlatformElementConfiguration<iOS, FormsElement> config, bool value)
+		{
+			SetApplyShadow(config.Element, value);
+			return config;
+		}
+
+		public static bool GetApplyShadow(this IPlatformElementConfiguration<iOS, FormsElement> config)
+		{
+			return GetApplyShadow(config.Element);
+		}
+		#endregion
+	}
+}
diff --git a/Xamarin.Forms.Platform.iOS/Renderers/PhoneMasterDetailRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/PhoneMasterDetailRenderer.cs
index 72b636303fe..6539a710995 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/PhoneMasterDetailRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/PhoneMasterDetailRenderer.cs
@@ -24,6 +24,7 @@ public class PhoneMasterDetailRenderer : UIViewController, IVisualElementRendere
 		UIGestureRecognizer _tapGesture;
 
 		VisualElementTracker _tracker;
+		bool _applyShadow;
 
 		Page Page => Element as Page;
 
@@ -235,6 +236,8 @@ void HandlePropertyChanged(object sender, PropertyChangedEventArgs e)
 				UpdateBackground();
 			else if (e.PropertyName == Page.BackgroundImageSourceProperty.PropertyName)
 				UpdateBackground();
+			else if (e.PropertyName == PlatformConfiguration.iOSSpecific.MasterDetailPage.ApplyShadowProperty.PropertyName)
+				UpdateApplyShadow(((MasterDetailPage)Element).OnThisPlatform().GetApplyShadow());
 		}
 
 		void LayoutChildren(bool animated)
@@ -257,7 +260,8 @@ void LayoutChildren(bool animated)
 			if (Presented)
 			{
 				target.X += masterFrame.Width;
-				opacity = 0.5f;
+				if (_applyShadow)
+					opacity = 0.5f;
 			}
 
 			if (isRTL)
@@ -367,6 +371,11 @@ void UpdateLeftBarButton()
 				NavigationRenderer.SetMasterLeftBarButton(firstPage, masterDetailPage);
 		}
 
+		void UpdateApplyShadow(bool value)
+		{
+			_applyShadow = value;
+		}
+
 		public override UIViewController ChildViewControllerForStatusBarHidden()
 		{
 			if (((MasterDetailPage)Element).Detail != null)
@@ -429,8 +438,11 @@ void UpdatePanGesture()
 							targetFrame.X = (nfloat)Math.Min(_masterController.View.Frame.Width, Math.Max(0, motion));
 
 						targetFrame.X = targetFrame.X * directionModifier;
-						var openProgress = targetFrame.X / _masterController.View.Frame.Width;
-						ApplyDetailShadow((nfloat)openProgress);
+						if (_applyShadow)
+						{
+							var openProgress = targetFrame.X / _masterController.View.Frame.Width;
+							ApplyDetailShadow((nfloat)openProgress);
+						}
 
 						detailView.Frame = targetFrame;
 						break;