[GH-10729] Added Current Page in Shell

Xamarin.Forms.Core.UnitTests/ShellModalTests.cs

@@ -345,6 +345,24 @@ public async Task NavigatingAndNavigatedFiresForShellModal()
 
 		}
 
+		[Test]
+		public async Task GetCurrentPageInModalNavigation()
+		{
+			Shell shell = new Shell();
+			shell.Items.Add(CreateShellItem(shellItemRoute: "NewRoute", shellSectionRoute: "Section", shellContentRoute: "Content"));
+
+			Page page = null;
+
+			shell.Navigated += (_, __) =>
+			{
+				page = shell.CurrentPage;
+			};
+
+			await shell.GoToAsync("ModalTestPage");
+			Assert.IsNotNull(page);
+			Assert.AreEqual(page.GetType(), typeof(ModalTestPage));
+		}
+
 
 		[QueryProperty("SomeQueryParameter", "SomeQueryParameter")]
 		public class ModalTestPageBase : ShellLifeCycleTests.LifeCyclePage

Xamarin.Forms.Core.UnitTests/ShellTests.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.Linq;
 using System.Threading.Tasks;
 using NUnit.Framework;
@@ -42,7 +42,7 @@ public void SetCurrentItemWithImplicitlyWrappedShellContent(bool useShellContent
 
 			BaseShellItem shellElement = null;
 
-			if(useShellContent)
+			if (useShellContent)
 				shellElement = CreateShellContent(shellContentRoute: "TestMe");
 			else
 				shellElement = CreateShellSection(shellSectionRoute: "TestMe");
@@ -632,7 +632,7 @@ public void CancelNavigation()
 
 		[Test]
 		public async Task OnBackbuttonPressedPageReturnsTrue()
-		{			
+		{
 			TestShell shell = new TestShell();
 
 			Routing.RegisterRoute("OnBackbuttonPressedFiresOnPage", typeof(ShellTestPage));
@@ -1135,7 +1135,7 @@ public async Task BaseShellItemNotVisible()
 		public async Task CantNavigateToNotVisibleShellItem()
 		{
 			var shell = new Shell();
-			var item1 = CreateShellItem(shellItemRoute:"NotVisible");
+			var item1 = CreateShellItem(shellItemRoute: "NotVisible");
 			var item2 = CreateShellItem();
 
 			shell.Items.Add(item1);
@@ -1545,6 +1545,77 @@ public void ClearingShellSectionAndReAddingSetsCurrentItem()
 		}
 
 		[Test]
+
+		public async Task GetCurrentPageInShellNavigation()
+		{
+			Shell shell = new Shell();
+			var item1 = CreateShellItem(asImplicit: true, shellContentRoute: "rootlevelcontent1");
+
+			shell.Items.Add(item1);
+			Routing.RegisterRoute("cat", typeof(ContentPage));
+
+			Page page = null;
+
+			shell.Navigated += (_, __) =>
+			{
+				page = shell.CurrentPage;
+			};
+
+			await shell.GoToAsync("cat");
+			Assert.IsNotNull(page);
+			Assert.AreEqual(page.GetType(), typeof(ContentPage));
+			Assert.AreEqual(shell.Navigation.NavigationStack[1], page);
+		}
+
+		[Test]
+		public async Task GetCurrentPageBetweenSections()
+		{
+			var shell = new Shell();
+			var one = new ShellItem { Route = "one" };
+			var two = new ShellItem { Route = "two" };
+
+			var tabone = MakeSimpleShellSection("tabone", "content");
+			var tabtwo = MakeSimpleShellSection("tabtwo", "content");
+			var tabthree = MakeSimpleShellSection("tabthree", "content");
+			var tabfour = MakeSimpleShellSection("tabfour", "content");
+
+			one.Items.Add(tabone);
+			one.Items.Add(tabtwo);
+
+			two.Items.Add(tabthree);
+			two.Items.Add(tabfour);
+
+			shell.Items.Add(one);
+			shell.Items.Add(two);
+
+			Page page = null;
+
+			shell.Navigated += (_, __) =>
+			{
+				page = shell.CurrentPage;
+			};
+
+			shell.GoToAsync(new ShellNavigationState("//two/tabfour/"));
+			Assert.IsNotNull(page);
+			Assert.AreEqual(page.GetType(), typeof(ShellTestPage));
+			Assert.AreEqual((tabfour as IShellSectionController).PresentedPage, page);
+		}
+
+		[Test]
+		public void GetCurrentPageOnInit()
+		{
+			var shell = new Shell();
+			Page page = null;
+			shell.Navigated += (_, __) =>
+			{
+				page = shell.CurrentPage;
+			};
+			var tabone = MakeSimpleShellSection("tabone", "content");
+			shell.Items.Add(tabone);
+			Assert.IsNotNull(page);
+		}
+
+
 		public async Task HotReloadStaysOnActiveItem()
 		{
 			Shell shell = new Shell();
@@ -1565,6 +1636,7 @@ public async Task HotReloadStaysOnActiveItem()
 			shell.Items.RemoveAt(0);
 
 			Assert.AreEqual("//item3", shell.CurrentState.Location.ToString());
+
 		}
 
 		[TestCase("ContentPage")]
@@ -1614,9 +1686,8 @@ public void SendStructureChangedFiresWhenAddingItems()
 			previousCount = count;
 			shell.CurrentItem.CurrentItem.Items.Add(CreateShellContent());
 			Assert.Greater(count, previousCount, "StructureChanged not fired when adding Shell Content");
-
-		}
 
+		}
 
 		//[Test]
 		//public void FlyoutItemLabelStyleCanBeChangedAfterRendered()

Xamarin.Forms.Core/Shell/Shell.cs

@@ -13,8 +13,10 @@
 namespace Xamarin.Forms
 {
 	[ContentProperty(nameof(Items))]
-	public class Shell : Page, IShellController, IPropertyPropagationController
+	public class Shell : Page, IShellController, IPropertyPropagationController, IPageContainer<Page>
 	{
+		public Page CurrentPage => (CurrentSection as IShellSectionController)?.PresentedPage;
+
 		public static readonly BindableProperty BackButtonBehaviorProperty =
 			BindableProperty.CreateAttached("BackButtonBehavior", typeof(BackButtonBehavior), typeof(Shell), null, BindingMode.OneTime,
 				propertyChanged: OnBackButonBehaviorPropertyChanged);
@@ -211,7 +213,7 @@ static void OnColorValueChanged(BindableObject bindable, object oldValue, object
 		DataTemplate IShellController.GetFlyoutItemDataTemplate(BindableObject bo)
 		{
 			BindableProperty bp = null;
-			string textBinding; 
+			string textBinding;
 			string iconBinding;
 			IStyleSelectable styleClassSource = null;
 
@@ -245,7 +247,7 @@ DataTemplate IShellController.GetFlyoutItemDataTemplate(BindableObject bo)
 				return (DataTemplate)bo.GetValue(bp);
 			}
 
-			if(IsSet(bp))
+			if (IsSet(bp))
 			{
 				return (DataTemplate)GetValue(bp);
 			}
@@ -563,7 +565,7 @@ await Device.InvokeOnMainThreadAsync(() =>
 						return CurrentItem.CurrentItem.GoToAsync(navigationRequest, queryData, animate);
 					});
 				}
-				else if(navigationRequest.Request.GlobalRoutes.Count == 0 &&
+				else if (navigationRequest.Request.GlobalRoutes.Count == 0 &&
 					navigationRequest.StackRequest == NavigationRequest.WhatToDoWithTheStack.ReplaceIt &&
 					currentShellSection?.Navigation?.NavigationStack?.Count > 1)
 				{
@@ -681,21 +683,21 @@ ShellNavigationState GetNavigationState(ShellItem shellItem, ShellSection shellS
 				}
 			}
 
-			if(routeStack.Count > 0)
+			if (routeStack.Count > 0)
 				routeStack.Insert(0, "/");
 
 			return String.Join("/", routeStack);
 
 
 			List<string> CollapsePath(
-				string myRoute, 
+				string myRoute,
 				List<string> currentRouteStack,
 				bool userDefinedRoute)
 			{
 				for (var i = currentRouteStack.Count - 1; i >= 0; i--)
 				{
 					var route = currentRouteStack[i];
-					if (Routing.IsImplicit(route) || 
+					if (Routing.IsImplicit(route) ||
 						(Routing.IsDefault(route) && userDefinedRoute))
 						currentRouteStack.RemoveAt(i);
 				}
@@ -705,7 +707,7 @@ List<string> CollapsePath(
 				// collapse similar leaves
 				int walkBackCurrentStackIndex = currentRouteStack.Count - (paths.Count - 1);
 
-				while(paths.Count > 1 && walkBackCurrentStackIndex >= 0)
+				while (paths.Count > 1 && walkBackCurrentStackIndex >= 0)
 				{
 					if (paths[0] == currentRouteStack[walkBackCurrentStackIndex])
 					{
@@ -1086,7 +1088,7 @@ async void NavigationPop()
 				{
 					await currentContent.Navigation.PopAsync();
 				}
-				catch(Exception exc)
+				catch (Exception exc)
 				{
 					Internals.Log.Warning(nameof(Shell), $"Failed to Navigate Back: {exc}");
 				}
@@ -1269,7 +1271,7 @@ static Dictionary<string, string> ParseQueryString(string query)
 		internal FlyoutBehavior GetEffectiveFlyoutBehavior()
 		{
 			ShellItem rootItem = null;
-			return GetEffectiveValue(Shell.FlyoutBehaviorProperty, 
+			return GetEffectiveValue(Shell.FlyoutBehaviorProperty,
 				() =>
 				{
 					if (this.IsSet(FlyoutBehaviorProperty))
@@ -1479,14 +1481,14 @@ protected override async Task<Page> OnPopModal(bool animated)
 						ModalStack[ModalStack.Count - 2].SendAppearing();
 				}
 
-				var modalPopped =  await base.OnPopModal(animated);
-				
+				var modalPopped = await base.OnPopModal(animated);
+
 				if (ModalStack.Count == 0 && !_shell.CurrentItem.CurrentItem.IsPoppingModalStack)
 					_shell.CurrentItem.SendAppearing();
-				
+
 				return modalPopped;
 			}
-			
+
 			protected override async Task OnPushModal(Page modal, bool animated)
 			{
 				if (ModalStack.Count == 0)
@@ -1497,25 +1499,25 @@ protected override async Task OnPushModal(Page modal, bool animated)
 
 				await base.OnPushModal(modal, animated);
 
-				modal.NavigationProxy.Inner = new NavigationImplWrapper(modal.NavigationProxy.Inner,  this);
+				modal.NavigationProxy.Inner = new NavigationImplWrapper(modal.NavigationProxy.Inner, this);
 			}
-			
-			
+
+
 			class NavigationImplWrapper : NavigationProxy
 			{
 				readonly INavigation _shellProxy;
 
 				public NavigationImplWrapper(INavigation proxy, INavigation shellProxy)
 				{
 					Inner = proxy;
-					_shellProxy = shellProxy;				
+					_shellProxy = shellProxy;
 
 				}
 
 				protected override Task<Page> OnPopModal(bool animated) => _shellProxy.PopModalAsync(animated);
 
 				protected override Task OnPushModal(Page modal, bool animated) => _shellProxy.PushModalAsync(modal, animated);
-			}			
+			}
 		}
 	}
 }