Fix RTL behavior for MasterDetailsPage when running on iOS 13 iPads (#7271)

* Fix RTL on iOS 13 tablets with MDP

* - add backgrounding extension for iOS
fixes #7224
fixes #7266

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue2818.cs

@@ -1,21 +1,41 @@
 using Xamarin.Forms.CustomAttributes;
 using Xamarin.Forms.Internals;
+using System;
+
+#if UITEST
+using Xamarin.UITest;
+using NUnit.Framework;
+#endif
 
 namespace Xamarin.Forms.Controls.Issues
 {
 	[Preserve(AllMembers = true)]
 	[Issue(IssueTracker.Github, 2818, "Right-to-Left MasterDetail in Xamarin.Forms Hamburger icon issue", PlatformAffected.Android)]
-	public class Issue2818 : MasterDetailPage
+	public class Issue2818 : TestMasterDetailPage
 	{
-		public Issue2818()
+
+		protected override void Init()
 		{
 			FlowDirection = FlowDirection.RightToLeft;
-
 			Master = new ContentPage
 			{
 				Title = "Master",
 				BackgroundColor = Color.SkyBlue,
-				IconImageSource = "menuIcon"
+				IconImageSource = "menuIcon",
+				Content = new StackLayout()
+				{
+					Children =
+					{
+						new Button()
+						{
+							Text = "If you can see me the test has passed",
+							AutomationId = "CloseMasterView",
+							Command = new Command(() => IsPresented = false)
+						}
+					},
+					AutomationId = "MasterLayout"
+				},
+				Padding = new Thickness(0, 42, 0, 0)
 			};
 
 			Detail = new NavigationPage(new ContentPage
@@ -26,21 +46,92 @@ namespace Xamarin.Forms.Controls.Issues
 					Children = {
 						new Label
 						{
-							Text = "The page must be with RightToLeft FlowDirection. Hamburger icon in main page must be going to right side."
+							Text = "The page must be with RightToLeft FlowDirection. Hamburger icon in main page must be going to right side. There should be visible text inside the Master View"
 						},
 						new Button
 						{
 							Text = "Set RightToLeft",
-							Command = new Command(() => FlowDirection = FlowDirection.RightToLeft)
+							Command = new Command(() => FlowDirection = FlowDirection.RightToLeft),
+							AutomationId = "ShowRightToLeft"
 						},
 						new Button
 						{
 							Text = "Set LeftToRight",
-							Command = new Command(() => FlowDirection = FlowDirection.LeftToRight)
+							Command = new Command(() => FlowDirection = FlowDirection.LeftToRight),
+							AutomationId = "ShowLeftToRight"
+						},
+						new Button
+						{
+							Text = "Open Master View",
+							Command = new Command(() => IsPresented = true),
+							AutomationId = "OpenMasterView"
+						},
+						new Label()
+						{
+							Text = Device.Idiom.ToString(),
+							AutomationId = "Idiom"
 						}
 					}
 				}
 			});
 		}
+
+#if UITEST
+		[Test]
+		public void MasterViewMovesAndContentIsVisible()
+		{
+			var idiom = RunningApp.WaitForElement("Idiom");
+
+			// This behavior is currently broken on a phone device Issue 7270
+			if (idiom[0].ReadText() != "Tablet")
+				return;
+
+			RunningApp.Tap("OpenMasterView");
+			RunningApp.Tap("CloseMasterView");
+			RunningApp.SetOrientationLandscape();
+			RunningApp.Tap("OpenMasterView");
+			var positionStart = RunningApp.WaitForElement("CloseMasterView");
+			RunningApp.Tap("ShowLeftToRight");
+
+			var results = RunningApp.QueryUntilPresent(() =>
+			{
+				var secondPosition = RunningApp.Query("CloseMasterView");
+
+				if (secondPosition.Length == 0)
+					return null;
+
+				if (secondPosition[0].Rect.X < positionStart[0].Rect.X)
+					return secondPosition;
+
+				return null;
+			});
+
+			Assert.IsNotNull(results, "Master View Did not change flow direction correctly");
+			Assert.AreEqual(1, results.Length, "Master View Did not change flow direction correctly");
+
+		}
+
+#if __IOS__
+		[Test]
+		public void MasterViewSizeDoesntChangeAfterBackground()
+		{
+			var idiom = RunningApp.WaitForElement("Idiom");
+			// This behavior is currently broken on a phone device Issue 7270
+			if (idiom[0].ReadText() != "Tablet")
+				return;
+		
+			RunningApp.SetOrientationLandscape();
+			RunningApp.Tap("CloseMasterView");
+			RunningApp.Tap("ShowLeftToRight");
+			var windowSize = RunningApp.WaitForElement("MasterLayout")[0];
+			RunningApp.SendAppToBackground(TimeSpan.FromSeconds(5));
+			var newWindowSize = RunningApp.WaitForElement("MasterLayout")[0];
+			Assert.AreEqual(newWindowSize.Rect.Width, windowSize.Rect.Width);
+			Assert.AreEqual(newWindowSize.Rect.Height, windowSize.Rect.Height);
+
+		}
+#endif
+
+#endif
 	}
 }

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/TestPages/ScreenshotConditionalApp.cs

@@ -4,6 +4,10 @@ using System.IO;
 using Xamarin.UITest;
 using Xamarin.UITest.Queries;
 
+#if __IOS__
+using Xamarin.UITest.iOS;
+#endif
+
 namespace Xamarin.Forms.Controls
 {
 	/// <summary>
@@ -445,6 +449,16 @@ namespace Xamarin.Forms.Controls
 		{
 			get { return _app.TestServer; }
 		}
+
+#if __IOS__
+		public void SendAppToBackground(TimeSpan timeSpan)
+		{
+			if (_app is iOSApp app)
+			{
+				app.SendAppToBackground(timeSpan);
+			}
+		}
+#endif
 	}
 }
 #endif

Xamarin.Forms.Core.UITests.Shared/Utilities/AppExtensions.cs

@@ -5,6 +5,9 @@ using Xamarin.UITest;
 using Xamarin.UITest.Queries;
 using System.Text.RegularExpressions;
 using System.Threading;
+#if __IOS__
+using Xamarin.UITest.iOS;
+#endif
 
 namespace Xamarin.UITest
 {
@@ -28,6 +31,17 @@ namespace Xamarin.UITest
 
 			return results;
 		}
+
+#if __IOS__
+		public static void SendAppToBackground(this IApp app, TimeSpan timeSpan)
+		{
+			if(app is Xamarin.Forms.Controls.ScreenshotConditionalApp sca)
+			{
+				sca.SendAppToBackground(timeSpan);
+				Thread.Sleep(timeSpan.Add(TimeSpan.FromSeconds(2)));
+			}
+		}
+#endif
 	}
 }
 

Xamarin.Forms.Platform.iOS/Extensions/FlowDirectionExtensions.cs

@@ -18,16 +18,25 @@ namespace Xamarin.Forms.Platform.iOS
 			}
 		}
 
-		internal static void UpdateFlowDirection(this UIView view, IVisualElementController controller)
+		internal static bool UpdateFlowDirection(this UIView view, IVisualElementController controller)
 		{
 			if (controller == null || view == null || !Forms.IsiOS9OrNewer)
-				return;
+				return false;
 
+			UISemanticContentAttribute updateValue = view.SemanticContentAttribute;
 
 			if (controller.EffectiveFlowDirection.IsRightToLeft())
-				view.SemanticContentAttribute = UISemanticContentAttribute.ForceRightToLeft;
+				updateValue = UISemanticContentAttribute.ForceRightToLeft;
 			else if (controller.EffectiveFlowDirection.IsLeftToRight())
-				view.SemanticContentAttribute = UISemanticContentAttribute.ForceLeftToRight;
+				updateValue = UISemanticContentAttribute.ForceLeftToRight;
+
+			if(updateValue != view.SemanticContentAttribute)
+			{
+				view.SemanticContentAttribute = updateValue;
+				return true;
+			}
+
+			return false;
 		}
 
 		internal static void UpdateTextAlignment(this UITextField control, IVisualElementController controller)

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

@@ -195,7 +195,11 @@ namespace Xamarin.Forms.Platform.iOS
 			if (layoutMaster)
 			{
 				var masterBounds = _masterController.View.Frame;
-				_masterWidth = (nfloat)Math.Max(_masterWidth, masterBounds.Width);
+
+				if (Forms.IsiOS13OrNewer)
+					_masterWidth = masterBounds.Width;
+				else
+					_masterWidth = (nfloat)Math.Max(_masterWidth, masterBounds.Width);
 
 				if (!masterBounds.IsEmpty)
 					MasterDetailPage.MasterBounds = new Rectangle(0, 0, _masterWidth, masterBounds.Height);
@@ -385,7 +389,12 @@ namespace Xamarin.Forms.Platform.iOS
 
 		void UpdateFlowDirection()
 		{
-			NativeView.UpdateFlowDirection(Element);
+			if(NativeView.UpdateFlowDirection(Element) && Forms.IsiOS13OrNewer && NativeView.Superview != null)
+			{
+				var view = NativeView.Superview;
+				NativeView.RemoveFromSuperview();
+				view.AddSubview(NativeView);
+			}
 		}
 
 		class InnerDelegate : UISplitViewControllerDelegate