Fix iOS so if you remove more than one page it's able to remove them successfully (#14383)

* Fix iOS Shell when removing multiple views

* - ui tests and fix navigate args

* - improve logic

* Update ShellSection.cs

* - update UI Tests

Xamarin.Forms.ControlGallery.iOS/Xamarin.Forms.ControlGallery.iOS.csproj

@@ -390,7 +390,7 @@
     </PackageReference>
     <PackageReference Include="Xam.Plugin.DeviceInfo" Version="3.0.2" />
     <PackageReference Include="Xamarin.Insights" Version="1.12.3" />
-    <PackageReference Include="Xamarin.TestCloud.Agent" Version="0.22.1" />
+    <PackageReference Include="Xamarin.TestCloud.Agent" Version="0.22.2" />
   </ItemGroup>
   <ItemGroup>
     <InterfaceDefinition Include="Resources\LaunchScreen.storyboard" />

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue13916.cs

@@ -0,0 +1,90 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Text;
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+
+
+#if UITEST
+using Xamarin.UITest;
+using NUnit.Framework;
+using Xamarin.Forms.Core.UITests;
+#endif
+
+namespace Xamarin.Forms.Controls.Issues
+{
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.Github, 13916, "[iOS] iOS Application crashes on Back press when navigated to using GoToAsync with \"//\" or \"///\" route if 2 or more things are removed from the navigation stack",
+		PlatformAffected.iOS)]
+#if UITEST
+	[NUnit.Framework.Category(Core.UITests.UITestCategories.Github5000)]
+	[NUnit.Framework.Category(UITestCategories.Shell)]
+#endif
+	public class Issue13916 : TestShell
+	{
+		static int pageCount = 1;
+		protected override void Init()
+		{
+			Routing.RegisterRoute(nameof(Issue13916SuccessPage), typeof(Issue13916SuccessPage));
+
+			AddFlyoutItem(CreateContentPage(), "Push Me");
+		}
+
+
+		public class Issue13916SuccessPage : ContentPage
+		{
+			public Issue13916SuccessPage()
+			{
+				StackLayout layout = new StackLayout();
+				Label label = new Label()
+				{
+					Text = "Success",
+					AutomationId = "Success"
+				};
+				layout.Children.Add(label);
+				Content = layout;
+			}
+		}
+
+		ContentPage CreateContentPage()
+		{
+			StackLayout layout = new StackLayout();
+			Button button = new Button()
+			{
+				Text = "Click Me",
+				AutomationId = $"ClickMe{pageCount}",
+				Command = new Command(async () =>
+				{
+					if (Navigation.NavigationStack.Count >= 3)
+					{
+						await GoToAsync($"../../{nameof(Issue13916SuccessPage)}");
+					}
+					else
+					{
+						await Navigation.PushAsync(CreateContentPage());
+					}
+				})
+			};
+			pageCount++;
+
+			layout.Children.Add(button);
+
+			return new ContentPage()
+			{
+				Content = layout
+			};
+		}
+
+#if UITEST
+		[Test]
+		public void RemovingMoreThanOneInnerPageAndThenPushingAPageCrashes()
+		{
+			RunningApp.Tap("ClickMe1");
+			RunningApp.Tap("ClickMe2");
+			RunningApp.Tap("ClickMe3");
+			RunningApp.WaitForElement("Success");
+		}
+#endif
+	}
+}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems

@@ -21,6 +21,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Issue13126.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue13126_2.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue13551.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Issue13916.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)RadioButtonTemplateFromStyle.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)ShellSearchHandlerItemSizing.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)ShellWithCustomRendererDisabledAnimations.cs" />

Xamarin.Forms.Core.Android.UITests/Xamarin.Forms.Core.Android.UITests.csproj

@@ -48,7 +48,7 @@
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
     <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="Xam.Plugin.DeviceInfo" Version="3.0.2" />
-    <PackageReference Include="Xamarin.UITest" Version="3.0.14" />
+    <PackageReference Include="Xamarin.UITest" Version="3.1.0" />
     <PackageReference Include="NUnit3TestAdapter">
       <Version>3.17.0</Version>
     </PackageReference>

Xamarin.Forms.Core.UnitTests/ShellNavigatedArgsTests.cs

@@ -0,0 +1,211 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Runtime.InteropServices;
+using System.Text;
+using System.Threading.Tasks;
+using NUnit.Framework;
+using Xamarin.Forms.Internals;
+
+namespace Xamarin.Forms.Core.UnitTests
+{
+	[TestFixture]
+	public class ShellNavigatedArgsTests : ShellTestBase
+	{
+		[TearDown]
+		public override void TearDown()
+		{
+			base.TearDown();
+			Routing.Clear();
+		}
+
+		[Test]
+		public async Task RemoveInnerPagesNavigatingArgs()
+		{
+			Routing.RegisterRoute("SecondPageView", typeof(ContentPage));
+			Routing.RegisterRoute("ThirdPageView", typeof(ContentPage));
+			Routing.RegisterRoute("FourthPage", typeof(ContentPage));
+
+			var shell = new TestShell(CreateShellItem<FlyoutItem>(shellContentRoute: "HomePageView"));
+
+			await shell.GoToAsync("//HomePageView/SecondPageView/ThirdPageView");
+			await shell.GoToAsync("//HomePageView/FourthPage");
+
+			shell.TestNavigatedArgs(ShellNavigationSource.Pop, "//HomePageView/SecondPageView/ThirdPageView", "//HomePageView/FourthPage");
+			Assert.AreEqual(3, shell.NavigatedCount);
+		}
+
+		[Test]
+		public async Task PopToRootSetsCorrectNavigationSource()
+		{
+			var shell = new TestShell(CreateShellItem());
+			await shell.Navigation.PushAsync(new ContentPage());
+			await shell.Navigation.PushAsync(new ContentPage());
+			await shell.Navigation.PopToRootAsync();
+			Assert.AreEqual(ShellNavigationSource.PopToRoot, shell.LastShellNavigatingEventArgs.Source);
+
+			await shell.Navigation.PushAsync(new ContentPage());
+			await shell.Navigation.PushAsync(new ContentPage());
+
+			await shell.Navigation.PopAsync();
+			Assert.AreEqual(ShellNavigationSource.Pop, shell.LastShellNavigatingEventArgs.Source);
+
+			await shell.Navigation.PopAsync();
+			Assert.AreEqual(ShellNavigationSource.PopToRoot, shell.LastShellNavigatingEventArgs.Source);
+		}
+
+		[Test]
+		public async Task PushingSetsCorrectNavigationSource()
+		{
+			var shell = new TestShell(CreateShellItem(shellItemRoute: "item1"));
+			shell.RegisterPage(nameof(PushingSetsCorrectNavigationSource));
+			await shell.GoToAsync(nameof(PushingSetsCorrectNavigationSource));
+
+			shell.TestNavigatingArgs(ShellNavigationSource.Push,
+				"//item1", $"{nameof(PushingSetsCorrectNavigationSource)}");
+
+			shell.TestNavigatedArgs(ShellNavigationSource.Push,
+				"//item1", $"//item1/{nameof(PushingSetsCorrectNavigationSource)}");
+		}
+
+		[Test]
+		public async Task ChangingShellItemSetsCorrectNavigationSource()
+		{
+			var shell = new TestShell(
+				CreateShellItem(shellItemRoute: "item1"),
+				CreateShellItem(shellItemRoute: "item2")
+			);
+
+			await shell.GoToAsync("//item2");
+
+			shell.TestNavigationArgs(ShellNavigationSource.ShellItemChanged,
+				"//item1", "//item2");
+		}
+
+		[Test]
+		public async Task ChangingShellSectionSetsCorrectNavigationSource()
+		{
+			var shell = new TestShell(
+				CreateShellItem(shellSectionRoute: "item1")
+			);
+
+			shell.Items[0].Items.Add(CreateShellSection(shellContentRoute: "item2"));
+
+			await shell.GoToAsync("//item2");
+
+			shell.TestNavigationArgs(ShellNavigationSource.ShellSectionChanged,
+				"//item1", "//item2");
+		}
+
+		[Test]
+		public async Task PoppingSamePageSetsCorrectNavigationSource()
+		{
+			Routing.RegisterRoute("detailspage", typeof(ContentPage));
+			var shell = new TestShell(CreateShellItem(shellItemRoute: "item1"));
+			await shell.GoToAsync("detailspage/detailspage");
+			await shell.Navigation.PopAsync();
+
+
+			shell.TestNavigatingArgs(ShellNavigationSource.Pop,
+				"//item1/detailspage/detailspage", $"..");
+
+			shell.TestNavigatedArgs(ShellNavigationSource.Pop,
+				"//item1/detailspage/detailspage", $"//item1/detailspage");
+		}
+
+		[Test]
+		public async Task ChangingShellContentSetsCorrectNavigationSource()
+		{
+			var shell = new TestShell(
+				CreateShellItem(shellContentRoute: "item1")
+			);
+
+			shell.Items[0].Items[0].Items.Add(CreateShellContent(shellContentRoute: "item2"));
+
+			await shell.GoToAsync("//item2");
+
+			shell.TestNavigationArgs(ShellNavigationSource.ShellContentChanged,
+				"//item1", "//item2");
+		}
+
+		[Test]
+		public async Task InsertPageSetsCorrectNavigationSource()
+		{
+			Routing.RegisterRoute("pagemiddle", typeof(ContentPage));
+			Routing.RegisterRoute("page", typeof(ContentPage));
+			var shell = new TestShell(
+				CreateShellItem(shellItemRoute: "item")
+			);
+
+			await shell.GoToAsync("//item/page");
+			await shell.GoToAsync("//item/pagemiddle/page");
+
+			shell.TestNavigationArgs(ShellNavigationSource.Insert,
+				"//item/page", "//item/pagemiddle/page");
+		}
+
+
+		[Test]
+		public async Task InsertPageFromINavigationSetsCorrectNavigationSource()
+		{
+			Routing.RegisterRoute("pagemiddle", typeof(ContentPage));
+			Routing.RegisterRoute("page", typeof(ContentPage));
+			var shell = new TestShell(
+				CreateShellItem(shellItemRoute: "item")
+			);
+
+			await shell.GoToAsync("//item/page");
+			ContentPage contentPage = new ContentPage();
+			Routing.SetRoute(contentPage, "pagemiddle");
+			shell.Navigation.InsertPageBefore(contentPage, shell.Navigation.NavigationStack.Last());
+
+			shell.TestNavigationArgs(ShellNavigationSource.Insert,
+				"//item/page", "//item/pagemiddle/page");
+		}
+
+
+		[Test]
+		public async Task RemovePageFromINavigationSetsCorrectNavigationSource()
+		{
+			Routing.RegisterRoute("pagemiddle", typeof(ContentPage));
+			Routing.RegisterRoute("page", typeof(ContentPage));
+			var shell = new TestShell(
+				CreateShellItem(shellItemRoute: "item")
+			);
+
+			await shell.GoToAsync("//item/pagemiddle/page");
+			shell.Navigation.RemovePage(shell.Navigation.NavigationStack[1]);
+
+			shell.TestNavigationArgs(ShellNavigationSource.Remove,
+				"//item/pagemiddle/page", "//item/page");
+		}
+
+		[Test]
+		public async Task RemovePageSetsCorrectNavigationSource()
+		{
+			Routing.RegisterRoute("pagemiddle", typeof(ContentPage));
+			Routing.RegisterRoute("page", typeof(ContentPage));
+			var shell = new TestShell(
+				CreateShellItem(shellItemRoute: "item")
+			);
+
+			await shell.GoToAsync("//item/pagemiddle/page");
+			await shell.GoToAsync("//item/page");
+
+
+			shell.TestNavigationArgs(ShellNavigationSource.Remove,
+				"//item/pagemiddle/page", "//item/page");
+		}
+
+		[Test]
+		public async Task InitialNavigatingArgs()
+		{
+			var shell = new TestShell(
+				CreateShellItem(shellItemRoute: "item")
+			);
+
+			shell.TestNavigationArgs(ShellNavigationSource.ShellItemChanged,
+				null, "//item");
+		}
+	}
+}

Xamarin.Forms.Core.UnitTests/ShellNavigatingTests.cs

@@ -488,22 +488,6 @@ namespace Xamarin.Forms.Core.UnitTests
 			Assert.AreEqual(3, tab.NavigationsFired.Count);
 		}
 
-		[Test]
-		public async Task PoppingSamePageSetsCorrectNavigationSource()
-		{
-			Routing.RegisterRoute("detailspage", typeof(ContentPage));
-			var shell = new TestShell(CreateShellItem(shellItemRoute: "item1"));
-			await shell.GoToAsync("detailspage/detailspage");
-			await shell.Navigation.PopAsync();
-
-
-			shell.TestNavigatingArgs(ShellNavigationSource.Pop,
-				"//item1/detailspage/detailspage", $"..");
-
-			shell.TestNavigatedArgs(ShellNavigationSource.Pop,
-				"//item1/detailspage/detailspage", $"//item1/detailspage");
-		}
-
 		[Test]
 		public async Task PoppingSetsCorrectNavigationSource()
 		{
@@ -522,127 +506,6 @@ namespace Xamarin.Forms.Core.UnitTests
 				"//item1/page1/page2", $"//item1/page1");
 		}
 
-		[Test]
-		public async Task PopToRootSetsCorrectNavigationSource()
-		{
-			var shell = new TestShell(CreateShellItem());
-			await shell.Navigation.PushAsync(new ContentPage());
-			await shell.Navigation.PushAsync(new ContentPage());
-			await shell.Navigation.PopToRootAsync();
-			Assert.AreEqual(ShellNavigationSource.PopToRoot, shell.LastShellNavigatingEventArgs.Source);
-
-			await shell.Navigation.PushAsync(new ContentPage());
-			await shell.Navigation.PushAsync(new ContentPage());
-
-			await shell.Navigation.PopAsync();
-			Assert.AreEqual(ShellNavigationSource.Pop, shell.LastShellNavigatingEventArgs.Source);
-
-			await shell.Navigation.PopAsync();
-			Assert.AreEqual(ShellNavigationSource.PopToRoot, shell.LastShellNavigatingEventArgs.Source);
-		}
-
-		[Test]
-		public async Task PushingSetsCorrectNavigationSource()
-		{
-			var shell = new TestShell(CreateShellItem(shellItemRoute: "item1"));
-			shell.RegisterPage(nameof(PushingSetsCorrectNavigationSource));
-			await shell.GoToAsync(nameof(PushingSetsCorrectNavigationSource));
-
-			shell.TestNavigatingArgs(ShellNavigationSource.Push,
-				"//item1", $"{nameof(PushingSetsCorrectNavigationSource)}");
-
-			shell.TestNavigatedArgs(ShellNavigationSource.Push,
-				"//item1", $"//item1/{nameof(PushingSetsCorrectNavigationSource)}");
-		}
-
-		[Test]
-		public async Task ChangingShellItemSetsCorrectNavigationSource()
-		{
-			var shell = new TestShell(
-				CreateShellItem(shellItemRoute: "item1"),
-				CreateShellItem(shellItemRoute: "item2")
-			);
-
-			await shell.GoToAsync("//item2");
-
-			shell.TestNavigationArgs(ShellNavigationSource.ShellItemChanged,
-				"//item1", "//item2");
-		}
-
-		[Test]
-		public async Task ChangingShellSectionSetsCorrectNavigationSource()
-		{
-			var shell = new TestShell(
-				CreateShellItem(shellSectionRoute: "item1")
-			);
-
-			shell.Items[0].Items.Add(CreateShellSection(shellContentRoute: "item2"));
-
-			await shell.GoToAsync("//item2");
-
-			shell.TestNavigationArgs(ShellNavigationSource.ShellSectionChanged,
-				"//item1", "//item2");
-		}
-
-		[Test]
-		public async Task ChangingShellContentSetsCorrectNavigationSource()
-		{
-			var shell = new TestShell(
-				CreateShellItem(shellContentRoute: "item1")
-			);
-
-			shell.Items[0].Items[0].Items.Add(CreateShellContent(shellContentRoute: "item2"));
-
-			await shell.GoToAsync("//item2");
-
-			shell.TestNavigationArgs(ShellNavigationSource.ShellContentChanged,
-				"//item1", "//item2");
-		}
-
-		[Test]
-		public async Task InsertPageSetsCorrectNavigationSource()
-		{
-			Routing.RegisterRoute("pagemiddle", typeof(ContentPage));
-			Routing.RegisterRoute("page", typeof(ContentPage));
-			var shell = new TestShell(
-				CreateShellItem(shellItemRoute: "item")
-			);
-
-			await shell.GoToAsync("//item/page");
-			await shell.GoToAsync("//item/pagemiddle/page");
-
-			shell.TestNavigationArgs(ShellNavigationSource.Insert,
-				"//item/page", "//item/pagemiddle/page");
-		}
-
-		[Test]
-		public async Task RemovePageSetsCorrectNavigationSource()
-		{
-			Routing.RegisterRoute("pagemiddle", typeof(ContentPage));
-			Routing.RegisterRoute("page", typeof(ContentPage));
-			var shell = new TestShell(
-				CreateShellItem(shellItemRoute: "item")
-			);
-
-			await shell.GoToAsync("//item/pagemiddle/page");
-			await shell.GoToAsync("//item/page");
-
-
-			shell.TestNavigationArgs(ShellNavigationSource.Remove,
-				"//item/pagemiddle/page", "//item/page");
-		}
-
-		[Test]
-		public async Task InitialNavigatingArgs()
-		{
-			var shell = new TestShell(
-				CreateShellItem(shellItemRoute: "item")
-			);
-
-			shell.TestNavigationArgs(ShellNavigationSource.ShellItemChanged,
-				null, "//item");
-		}
-
 
 		[TestCase(true, 2)]
 		[TestCase(false, 2)]

Xamarin.Forms.Core.UnitTests/ShellTestBase.cs

@@ -374,8 +374,6 @@ namespace Xamarin.Forms.Core.UnitTests
 				OnNavigatingCount++;
 			}
 
-
-
 			public void TestNavigationArgs(ShellNavigationSource source, string from, string to)
 			{
 				TestNavigatingArgs(source, from, to);
@@ -392,6 +390,7 @@ namespace Xamarin.Forms.Core.UnitTests
 					Assert.AreEqual(from, this.LastShellNavigatedEventArgs.Previous.Location.ToString());
 
 				Assert.AreEqual(to, this.LastShellNavigatedEventArgs.Current.Location.ToString());
+				Assert.AreEqual(to, this.CurrentState.Location.ToString());
 			}
 
 			public void TestNavigatingArgs(ShellNavigationSource source, string from, string to)

Xamarin.Forms.Core.UnitTests/Xamarin.Forms.Core.UnitTests.csproj

@@ -94,6 +94,7 @@
     <Compile Include="ShellFlyoutItemGroupTests.cs" />
     <Compile Include="ShellFlyoutItemTemplateTests.cs" />
     <Compile Include="ShellModalTests.cs" />
+    <Compile Include="ShellNavigatedArgsTests.cs" />
     <Compile Include="ShellNavigationStateTests.cs" />
     <Compile Include="ShellNavigatingTests.cs" />
     <Compile Include="ShellTestBase.cs" />

Xamarin.Forms.Core.Windows.UITests/Xamarin.Forms.Core.Windows.UITests.csproj

@@ -53,7 +53,7 @@
     <PackageReference Include="Selenium.Support" Version="3.141.0" />
     <PackageReference Include="Selenium.WebDriver" Version="3.141.0" />
     <PackageReference Include="Xam.Plugin.DeviceInfo" Version="3.0.2" />
-    <PackageReference Include="Xamarin.UITest" Version="3.0.14" />
+    <PackageReference Include="Xamarin.UITest" Version="3.1.0" />
     <PackageReference Include="NUnit3TestAdapter">
       <Version>3.17.0</Version>
     </PackageReference>

Xamarin.Forms.Core.iOS.UITests/Xamarin.Forms.Core.iOS.UITests.csproj

@@ -49,7 +49,7 @@
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
     <PackageReference Include="NUnit" Version="3.13.1" />
     <PackageReference Include="Xam.Plugin.DeviceInfo" Version="3.0.2" />
-    <PackageReference Include="Xamarin.UITest" Version="3.0.14" />
+    <PackageReference Include="Xamarin.UITest" Version="3.1.0" />
     <PackageReference Include="NUnit3TestAdapter">
       <Version>3.17.0</Version>
     </PackageReference>

Xamarin.Forms.Core.macOS.UITests/Xamarin.Forms.Core.macOS.UITests.csproj

@@ -53,7 +53,7 @@
     <PackageReference Include="ServiceStack.Interfaces" Version="4.5.12" />
     <PackageReference Include="ServiceStack.Text" Version="4.5.12" />
     <PackageReference Include="Xam.Plugin.DeviceInfo" Version="3.0.2" />
-    <PackageReference Include="Xamarin.UITest" Version="3.0.14" />
+    <PackageReference Include="Xamarin.UITest" Version="3.1.0" />
     <PackageReference Include="Xamarin.UITest.Desktop" Version="0.0.7" />
   </ItemGroup>
   <ItemGroup>

Xamarin.Forms.Core/Shell/Shell.cs

@@ -468,10 +468,13 @@ namespace Xamarin.Forms
 			var modalStack = shellSection?.Navigation?.ModalStack;
 			var result = ShellNavigationManager.GetNavigationState(shellItem, shellSection, shellContent, stack, modalStack);
 
-			SetValueFromRenderer(CurrentStatePropertyKey, result);
-
-			_navigationManager.HandleNavigated(new ShellNavigatedEventArgs(oldState, CurrentState, source));
+			if (result?.Location != oldState?.Location)
+			{
+				SetValueFromRenderer(CurrentStatePropertyKey, result);
+				_navigationManager.HandleNavigated(new ShellNavigatedEventArgs(oldState, CurrentState, source));
+			}
 		}
+
 		ReadOnlyCollection<ShellItem> IShellController.GetItems() =>
 			new ReadOnlyCollection<ShellItem>(((ShellItemCollection)Items).VisibleItemsReadOnly.ToList());
 

Xamarin.Forms.Core/Shell/ShellNavigationManager.cs

@@ -11,7 +11,7 @@ namespace Xamarin.Forms
 		readonly Shell _shell;
 		ShellNavigatedEventArgs _accumulatedEvent;
 		bool _accumulateNavigatedEvents;
-
+		public bool AccumulateNavigatedEvents => _accumulateNavigatedEvents;
 		public event EventHandler<ShellNavigatedEventArgs> Navigated;
 		public event EventHandler<ShellNavigatingEventArgs> Navigating;
 
@@ -166,6 +166,7 @@ namespace Xamarin.Forms
 				await _shell.CurrentItem.CurrentItem.GoToAsync(navigationRequest, queryData, animate, isRelativePopping);
 			}
 
+			(_shell as IShellController).UpdateCurrentState(source);
 			_accumulateNavigatedEvents = false;
 
 			// this can be null in the event that no navigation actually took place!

Xamarin.Forms.Core/Shell/ShellSection.cs

@@ -116,7 +116,6 @@ namespace Xamarin.Forms
 			await poppingCompleted;
 
 			RemovePage(page);
-			SendUpdateCurrentState(ShellNavigationSource.Pop);
 		}
 
 		async void IShellSectionController.SendPoppingToRoot(Task finishedPopping)
@@ -135,8 +134,6 @@ namespace Xamarin.Forms
 
 			for (int i = 1; i < oldStack.Count; i++)
 				RemovePage(oldStack[i]);
-
-			SendUpdateCurrentState(ShellNavigationSource.PopToRoot);
 		}
 
 		[Obsolete]
@@ -151,8 +148,6 @@ namespace Xamarin.Forms
 			_navStack.Remove(last);
 
 			RemovePage(last);
-
-			SendUpdateCurrentState(ShellNavigationSource.Pop);
 		}
 
 		// we want the list returned from here to remain point in time accurate
@@ -178,7 +173,6 @@ namespace Xamarin.Forms
 				_navStack.Remove(page);
 
 			RemovePage(page);
-			SendUpdateCurrentState(ShellNavigationSource.Pop);
 		}
 
 
@@ -572,7 +566,7 @@ namespace Xamarin.Forms
 
 			if (Parent?.Parent is IShellController shell)
 			{
-				shell.UpdateCurrentState(ShellNavigationSource.ShellSectionChanged);
+				//shell.UpdateCurrentState(ShellNavigationSource.ShellSectionChanged);
 			}
 		}
 
@@ -724,8 +718,6 @@ namespace Xamarin.Forms
 			};
 
 			_navigationRequested?.Invoke(this, args);
-
-			SendUpdateCurrentState(ShellNavigationSource.Insert);
 		}
 
 		protected async virtual Task<Page> OnPopAsync(bool animated)
@@ -762,8 +754,6 @@ namespace Xamarin.Forms
 				await args.Task;
 			RemovePage(page);
 
-			SendUpdateCurrentState(ShellNavigationSource.Pop);
-
 			return page;
 		}
 
@@ -804,7 +794,6 @@ namespace Xamarin.Forms
 			}
 
 			PresentedPageAppearing();
-			SendUpdateCurrentState(ShellNavigationSource.PopToRoot);
 		}
 
 		protected virtual Task OnPushAsync(Page page, bool animated)
@@ -834,8 +823,6 @@ namespace Xamarin.Forms
 			AddPage(page);
 			_navigationRequested?.Invoke(this, args);
 
-			SendUpdateCurrentState(ShellNavigationSource.Push);
-
 			if (args.Task == null)
 				return Task.FromResult(true);
 			return args.Task;
@@ -867,8 +854,6 @@ namespace Xamarin.Forms
 					bool isAnimated = animated ?? (Shell.GetPresentationMode(pageToPop) & PresentationMode.NotAnimated) != PresentationMode.NotAnimated;
 					await Navigation.PopModalAsync(isAnimated);
 				}
-
-				((IShellController)Shell).UpdateCurrentState(ShellNavigationSource.ShellSectionChanged);
 			}
 			finally
 			{
@@ -911,8 +896,6 @@ namespace Xamarin.Forms
 				RequestType = NavigationRequestType.Remove
 			};
 			_navigationRequested?.Invoke(this, args);
-
-			SendUpdateCurrentState(ShellNavigationSource.Remove);
 		}
 
 		internal bool IsVisibleSection => Parent?.Parent is Shell shell && shell.CurrentItem?.CurrentItem == this;
@@ -1013,14 +996,6 @@ namespace Xamarin.Forms
 
 		void SendAppearanceChanged() => ((IShellController)Parent?.Parent)?.AppearanceChanged(this, false);
 
-		void SendUpdateCurrentState(ShellNavigationSource source)
-		{
-			if (Parent?.Parent is IShellController shell)
-			{
-				shell.UpdateCurrentState(source);
-			}
-		}
-
 		protected override void OnBindingContextChanged()
 		{
 			base.OnBindingContextChanged();
@@ -1051,8 +1026,6 @@ namespace Xamarin.Forms
 
 			protected override IReadOnlyList<Page> GetNavigationStack() => _owner.GetNavigationStack();
 
-			protected override void OnInsertPageBefore(Page page, Page before) => _owner.OnInsertPageBefore(page, before);
-
 			protected override async Task<Page> OnPopAsync(bool animated)
 			{
 				if (!_owner.IsVisibleSection)
@@ -1116,7 +1089,64 @@ namespace Xamarin.Forms
 				return _owner.Shell.NavigationManager.GoToAsync(navigationParameters);
 			}
 
-			protected override void OnRemovePage(Page page) => _owner.OnRemovePage(page);
+			protected override void OnRemovePage(Page page)
+			{
+				if (!_owner.IsVisibleSection || _owner.Shell.NavigationManager.AccumulateNavigatedEvents)
+				{
+					_owner.OnRemovePage(page);
+					return;
+				}
+
+				var stack = _owner.Stack.ToList();
+				stack.Remove(page);
+				var navigationState = GetUpdatedStatus(stack);
+
+				ShellNavigatingEventArgs shellNavigatingEventArgs = new ShellNavigatingEventArgs(
+					_owner.Shell.CurrentState,
+					navigationState.Location,
+					ShellNavigationSource.Remove,
+					false);
+
+				_owner.Shell.NavigationManager.HandleNavigating(shellNavigatingEventArgs);
+				_owner.OnRemovePage(page);
+				(_owner.Shell as IShellController).UpdateCurrentState(ShellNavigationSource.Remove);
+			}
+
+			protected override void OnInsertPageBefore(Page page, Page before)
+			{
+				if (!_owner.IsVisibleSection || _owner.Shell.NavigationManager.AccumulateNavigatedEvents)
+				{
+					_owner.OnInsertPageBefore(page, before);
+					return;
+				}
+
+				var stack = _owner.Stack.ToList();
+				var index = stack.IndexOf(before);
+				if (index == -1)
+					throw new ArgumentException("Page not found in nav stack");
+
+				stack.Insert(index, page);
+				var navigationState = GetUpdatedStatus(stack);
+
+				ShellNavigatingEventArgs shellNavigatingEventArgs = new ShellNavigatingEventArgs(
+					_owner.Shell.CurrentState,
+					navigationState.Location,
+					ShellNavigationSource.Insert,
+					false);
+
+				_owner.Shell.NavigationManager.HandleNavigating(shellNavigatingEventArgs);
+				_owner.OnInsertPageBefore(page, before);
+				(_owner.Shell as IShellController).UpdateCurrentState(ShellNavigationSource.Insert);
+			}
+
+			ShellNavigationState GetUpdatedStatus(IReadOnlyList<Page> stack)
+			{
+				var shellItem = _owner.Shell.CurrentItem;
+				var shellSection = shellItem?.CurrentItem;
+				var shellContent = shellSection?.CurrentItem;
+				var modalStack = shellSection?.Navigation?.ModalStack;
+				return ShellNavigationManager.GetNavigationState(shellItem, shellSection, shellContent, stack, modalStack);
+			}
 		}
 	}
 }

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

@@ -68,19 +68,33 @@ namespace Xamarin.Forms.Platform.iOS
 		ShellSection _shellSection;
 		bool _ignorePopCall;
 
+		// When setting base.ViewControllers iOS doesn't modify the property right away. 
+		// if you set base.ViewControllers to a new array and then retrieve base.ViewControllers
+		// iOS will return the previous array until the new array has been processed
+		// This means if you try to remove one VC and then try to remove a second VC before the first one is processed
+		// you'll end up re-adding back the first VC
+		// ViewControllers = ViewControllers.Remove(vc1)
+		// ViewControllers = ViewControllers.Remove(vc2)  
+		// You've now added vc1 back because the second call to ViewControllers will still return a ViewControllers list with vc1 in it
+		UIViewController[] _pendingViewControllers;
+
 		public ShellSectionRenderer(IShellContext context) : base()
 		{
 			Delegate = new NavDelegate(this);
 			_context = context;
 			_context.Shell.PropertyChanged += HandleShellPropertyChanged;
+			_context.Shell.Navigated += OnNavigated;
+			_context.Shell.Navigating += OnNavigating;
 		}
 
-		public ShellSectionRenderer(IShellContext context, Type navigationBarType, Type toolbarType) 
+		public ShellSectionRenderer(IShellContext context, Type navigationBarType, Type toolbarType)
 			: base(navigationBarType, toolbarType)
 		{
 			Delegate = new NavDelegate(this);
 			_context = context;
 			_context.Shell.PropertyChanged += HandleShellPropertyChanged;
+			_context.Shell.Navigated += OnNavigated;
+			_context.Shell.Navigating += OnNavigating;
 		}
 
 		[Export("navigationBar:shouldPopItem:")]
@@ -89,14 +103,14 @@ namespace Xamarin.Forms.Platform.iOS
 			SendPop();
 
 		internal bool SendPop()
-		{ 
+		{
 			// this means the pop is already done, nothing we can do
-			if (ViewControllers.Length < NavigationBar.Items.Length)
+			if (ActiveViewControllers().Length < NavigationBar.Items.Length)
 				return true;
 
-			foreach(var tracker in _trackers)
+			foreach (var tracker in _trackers)
 			{
-				if(tracker.Value.ViewController == TopViewController)
+				if (tracker.Value.ViewController == TopViewController)
 				{
 					var behavior = Shell.GetBackButtonBehavior(tracker.Value.Page);
 					var command = behavior.GetPropertyIfSet<ICommand>(BackButtonBehavior.CommandProperty, null);
@@ -104,7 +118,7 @@ namespace Xamarin.Forms.Platform.iOS
 
 					if (command != null)
 					{
-						if(command.CanExecute(commandParameter))
+						if (command.CanExecute(commandParameter))
 						{
 							command.Execute(commandParameter);
 						}
@@ -202,6 +216,8 @@ namespace Xamarin.Forms.Platform.iOS
 			if (_context.Shell != null)
 			{
 				_context.Shell.PropertyChanged -= HandleShellPropertyChanged;
+				_context.Shell.Navigated -= OnNavigated;
+				_context.Shell.Navigating -= OnNavigating;
 				((IShellController)_context.Shell).RemoveAppearanceObserver(this);
 			}
 
@@ -263,7 +279,7 @@ namespace Xamarin.Forms.Platform.iOS
 			_renderer = CreateShellSectionRootRenderer(ShellSection, _context);
 
 			PushViewController(_renderer.ViewController, false);
-			
+
 			var stack = ShellSection.Stack;
 			for (int i = 1; i < stack.Count; i++)
 			{
@@ -307,7 +323,7 @@ namespace Xamarin.Forms.Platform.iOS
 
 			_trackers[page] = tracker;
 
-			ViewControllers.Insert(ViewControllers.IndexOf(beforeRenderer.ViewController), renderer.ViewController);
+			InsertViewController(ActiveViewControllers().IndexOf(beforeRenderer.ViewController), renderer.ViewController);
 		}
 
 		protected virtual void OnNavigationRequested(object sender, NavigationRequestedEventArgs e)
@@ -353,7 +369,7 @@ namespace Xamarin.Forms.Platform.iOS
 
 		public override UIViewController[] PopToRootViewController(bool animated)
 		{
-			if (!_ignorePopCall && ViewControllers.Length > 1)
+			if (!_ignorePopCall && ActiveViewControllers().Length > 1)
 			{
 				ProcessPopToRoot();
 			}
@@ -432,9 +448,7 @@ namespace Xamarin.Forms.Platform.iOS
 					OnPopRequested(e);
 				}
 
-				if(ViewControllers.Contains(viewController))
-					ViewControllers = ViewControllers.Remove(viewController);
-
+				RemoveViewController(viewController);
 				DisposePage(page);
 			}
 		}
@@ -461,8 +475,11 @@ namespace Xamarin.Forms.Platform.iOS
 		{
 			if (_trackers.TryGetValue(page, out var tracker))
 			{
-				if(!calledFromDispose && tracker.ViewController != null && ViewControllers.Contains(tracker.ViewController))
-					ViewControllers = ViewControllers.Remove(_trackers[page].ViewController);
+				if (!calledFromDispose && tracker.ViewController != null && ActiveViewControllers().Contains(tracker.ViewController))
+				{
+					System.Diagnostics.Debug.Write($"Disposing {_trackers[page].ViewController.GetHashCode()}");
+					RemoveViewController(_trackers[page].ViewController);
+				}
 
 				tracker.Dispose();
 				_trackers.Remove(page);
@@ -502,6 +519,70 @@ namespace Xamarin.Forms.Platform.iOS
 				UpdateNavigationBarHasShadow();
 		}
 
+		// We only care about using pendingViewControllers when we are setting the ViewControllers array directly
+		// So, once navigation starts again (or ends) we can just clear the pendingViewControllers
+		void OnNavigating(object sender, ShellNavigatingEventArgs e)
+		{
+			_pendingViewControllers = null;
+		}
+
+		void OnNavigated(object sender, ShellNavigatedEventArgs e)
+		{
+			_pendingViewControllers = null;
+		}
+
+		// These are all just safety nets to ensure that _pendingViewControllers doesn't for some reason get out of sync
+		// and start causing issues. In theory we could just override ViewControllers here to make sure _pendingViewControllers
+		// stays in sync but I don't trust that `ViewControllers.set` is reliably called with every modification
+		public override UIViewController[] ViewControllers
+		{
+			get => base.ViewControllers;
+			set
+			{
+				if (_pendingViewControllers != null)
+					_pendingViewControllers = value;
+
+				base.ViewControllers = value;
+			}
+		}
+
+		public override UIViewController[] PopToViewController(UIViewController viewController, bool animated)
+		{
+			_pendingViewControllers = null;
+			return base.PopToViewController(viewController, animated);
+		}
+
+		public override void PushViewController(UIViewController viewController, bool animated)
+		{
+			_pendingViewControllers = null;
+			base.PushViewController(viewController, animated);
+		}
+
+		public override UIViewController PopViewController(bool animated)
+		{
+			_pendingViewControllers = null;
+			return base.PopViewController(animated);
+		}
+
+		UIViewController[] ActiveViewControllers() =>
+			_pendingViewControllers ?? base.ViewControllers;
+
+		void RemoveViewController(UIViewController viewController)
+		{
+			_pendingViewControllers = _pendingViewControllers ?? base.ViewControllers;
+			if (_pendingViewControllers.Contains(viewController))
+				_pendingViewControllers = _pendingViewControllers.Remove(viewController);
+
+			ViewControllers = _pendingViewControllers;
+		}
+
+		void InsertViewController(int index, UIViewController viewController)
+		{
+			_pendingViewControllers = _pendingViewControllers ?? base.ViewControllers;
+			_pendingViewControllers = _pendingViewControllers.Insert(index, viewController);
+			ViewControllers = _pendingViewControllers;
+		}
+
 		void PushPage(Page page, bool animated, TaskCompletionSource<bool> completionSource = null)
 		{
 			var renderer = Platform.CreateRenderer(page);
@@ -576,7 +657,7 @@ namespace Xamarin.Forms.Platform.iOS
 
 			public override bool ShouldBegin(UIGestureRecognizer recognizer)
 			{
-				if (_parent.ViewControllers.Length == 1)
+				if ((_parent as ShellSectionRenderer).ActiveViewControllers().Length == 1)
 					return false;
 				return _shouldPop();
 			}
@@ -619,6 +700,7 @@ namespace Xamarin.Forms.Platform.iOS
 
 			public override void WillShowViewController(UINavigationController navigationController, [Transient] UIViewController viewController, bool animated)
 			{
+				System.Diagnostics.Debug.Write($"WillShowViewController {viewController.GetHashCode()}");
 				var element = _self.ElementForViewController(viewController);
 
 				bool navBarVisible;