Added a util method to get services from the handler (#676)

src/Core/src/Handlers/Button/ButtonHandler.Android.cs

@@ -73,9 +73,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(ButtonHandler handler, IButton button)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(button, fontManager);
 		}

src/Core/src/Handlers/Button/ButtonHandler.Windows.cs

@@ -65,9 +65,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(ButtonHandler handler, IButton button)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(button, fontManager);
 		}

src/Core/src/Handlers/Button/ButtonHandler.iOS.cs

@@ -70,9 +70,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(ButtonHandler handler, IButton button)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(button, fontManager);
 		}

src/Core/src/Handlers/DatePicker/DatePickerHandler.Android.cs

@@ -76,9 +76,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(DatePickerHandler handler, IDatePicker datePicker)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(datePicker, fontManager);
 		}

src/Core/src/Handlers/DatePicker/DatePickerHandler.iOS.cs

@@ -91,9 +91,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(DatePickerHandler handler, IDatePicker datePicker)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(datePicker, fontManager);
 		}

src/Core/src/Handlers/Editor/EditorHandler.Android.cs

@@ -69,9 +69,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(EditorHandler handler, IEditor editor)
 		{
-			var services = handler.Services
-				   ?? throw new InvalidOperationException($"Unable to find service provider, the handler.Services was null.");
-			var fontManager = services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(editor, fontManager);
 		}

src/Core/src/Handlers/Editor/EditorHandler.iOS.cs

@@ -110,9 +110,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(EditorHandler handler, IEditor editor)
 		{
-			var services = handler.Services ??
-				throw new InvalidOperationException($"Unable to find service provider, the handler.Services was null.");
-			var fontManager = services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(editor, fontManager);
 		}

src/Core/src/Handlers/Entry/EntryHandler.Android.cs

@@ -95,9 +95,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(EntryHandler handler, IEntry entry)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(entry, fontManager);
 		}

src/Core/src/Handlers/Entry/EntryHandler.iOS.cs

@@ -95,9 +95,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(EntryHandler handler, IEntry entry)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(entry, fontManager);
 		}

src/Core/src/Handlers/Label/LabelHandler.Android.cs

@@ -68,9 +68,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(LabelHandler handler, ILabel label)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(label, fontManager);
 		}

src/Core/src/Handlers/Label/LabelHandler.Windows.cs

@@ -26,9 +26,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(LabelHandler handler, ILabel label)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.TextBlock?.UpdateFont(label, fontManager);
 		}

src/Core/src/Handlers/Label/LabelHandler.iOS.cs

@@ -53,9 +53,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(LabelHandler handler, ILabel label)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(label, fontManager);
 		}

src/Core/src/Handlers/Picker/PickerHandler.Android.cs

@@ -52,9 +52,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(PickerHandler handler, IPicker picker)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(picker, fontManager);
 		}

src/Core/src/Handlers/Picker/PickerHandler.iOS.cs

@@ -109,9 +109,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(PickerHandler handler, IPicker picker)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(picker, fontManager);
 		}

src/Core/src/Handlers/SearchBar/SearchBarHandler.Android.cs

@@ -32,9 +32,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(SearchBarHandler handler, ISearchBar searchBar)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(searchBar, fontManager, handler._editText);
 		}

src/Core/src/Handlers/SearchBar/SearchBarHandler.iOS.cs

@@ -34,9 +34,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(SearchBarHandler handler, ISearchBar searchBar)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.QueryEditor?.UpdateFont(searchBar, fontManager);
 		}

src/Core/src/Handlers/TimePicker/TimePickerHandler.Android.cs

@@ -62,9 +62,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(TimePickerHandler handler, ITimePicker timePicker)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(timePicker, fontManager);
 		}

src/Core/src/Handlers/TimePicker/TimePickerHandler.iOS.cs

@@ -47,9 +47,7 @@ namespace Microsoft.Maui.Handlers
 
 		public static void MapFont(TimePickerHandler handler, ITimePicker timePicker)
 		{
-			_ = handler.Services ?? throw new InvalidOperationException($"{nameof(Services)} should have been set by base class.");
-
-			var fontManager = handler.Services.GetRequiredService<IFontManager>();
+			var fontManager = handler.GetRequiredService<IFontManager>();
 
 			handler.NativeView?.UpdateFont(timePicker, fontManager);
 		}

src/Core/src/Handlers/View/ViewHandler.cs

@@ -1,3 +1,4 @@
+using System;
 #if __IOS__
 using NativeView = UIKit.UIView;
 #elif __MACOS__
@@ -52,6 +53,8 @@ namespace Microsoft.Maui.Handlers
 
 		public IMauiContext? MauiContext { get; private set; }
 
+		public IServiceProvider? Services => MauiContext?.Services;
+
 		public object? NativeView { get; private protected set; }
 
 		public IView? VirtualView { get; private protected set; }

src/Core/src/Handlers/View/ViewHandlerOfT.cs

@@ -41,8 +41,6 @@ namespace Microsoft.Maui.Handlers
 			private set => base.NativeView = value;
 		}
 
-		public IServiceProvider? Services => MauiContext?.Services;
-
 		public override void SetVirtualView(IView view)
 		{
 			_ = view ?? throw new ArgumentNullException(nameof(view));

src/Core/src/Platform/ViewHandlerExtensions.cs

@@ -0,0 +1,23 @@
+using System;
+using Microsoft.Extensions.DependencyInjection;
+using Microsoft.Maui.Handlers;
+
+namespace Microsoft.Maui
+{
+	internal static class ViewHandlerExtensions
+	{
+		public static T GetRequiredService<T>(this ViewHandler handler)
+			where T : notnull
+		{
+			var context = handler.MauiContext ??
+				throw new InvalidOperationException($"Unable to find the context. The {nameof(ViewHandler.MauiContext)} property should have been set by the host.");
+
+			var services = context?.Services ??
+				throw new InvalidOperationException($"Unable to find the service provider. The {nameof(ViewHandler.MauiContext)} property should have been set by the host.");
+
+			var service = services.GetRequiredService<T>();
+
+			return service;
+		}
+	}
+}

src/Core/tests/UnitTests/AbstractViewHandlerTests.cs

@@ -1,3 +1,6 @@
+using System;
+using Microsoft.Extensions.DependencyInjection.Extensions;
+using Microsoft.Maui.Hosting.Internal;
 using Xunit;
 
 namespace Microsoft.Maui.UnitTests
@@ -36,5 +39,55 @@ namespace Microsoft.Maui.UnitTests
 			Assert.Equal(2, handlerStub.ConnectHandlerCount);
 			Assert.Equal(2, handlerStub.DisconnectHandlerCount);
 		}
+
+		[Fact]
+		public void GetRequiredServiceThrowsOnNoContext()
+		{
+			HandlerStub handlerStub = new HandlerStub();
+
+			Assert.Null(handlerStub.MauiContext);
+
+			var ex = Assert.Throws<InvalidOperationException>(() => handlerStub.GetRequiredService<IFooService>());
+
+			Assert.Contains("the context", ex.Message);
+			Assert.Contains("MauiContext", ex.Message);
+		}
+
+		[Fact]
+		public void GetRequiredServiceThrowsOnNoServices()
+		{
+			HandlerStub handlerStub = new HandlerStub();
+
+			handlerStub.SetMauiContext(new InvalidHandlersContextStub());
+
+			Assert.NotNull(handlerStub.MauiContext);
+			Assert.Null(handlerStub.MauiContext.Services);
+
+			var ex = Assert.Throws<InvalidOperationException>(() => handlerStub.GetRequiredService<IFooService>());
+
+			Assert.Contains("the service provider", ex.Message);
+			Assert.Contains("MauiContext", ex.Message);
+		}
+
+		[Fact]
+		public void GetRequiredServiceRetrievesService()
+		{
+			HandlerStub handlerStub = new HandlerStub();
+
+			var collection = new MauiServiceCollection();
+			collection.TryAddSingleton<IMauiHandlersServiceProvider>(new MauiHandlersServiceProvider(new MauiServiceCollection()));
+			collection.TryAddSingleton<IFooService, FooService>();
+
+			var provider = new MauiServiceProvider(collection, false);
+
+			handlerStub.SetMauiContext(new HandlersContextStub(provider));
+
+			Assert.NotNull(handlerStub.MauiContext);
+			Assert.NotNull(handlerStub.MauiContext.Services);
+
+			var foo = handlerStub.GetRequiredService<IFooService>();
+
+			Assert.IsType<FooService>(foo);
+		}
 	}
-}
+}

src/Core/tests/UnitTests/Hosting/HostBuilderAppTests.cs

@@ -1,6 +1,5 @@
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Maui.Hosting;
-using Microsoft.Maui.Tests;
 using Xunit;
 
 namespace Microsoft.Maui.UnitTests

src/Core/tests/UnitTests/Hosting/HostBuilderHandlerTests.cs

@@ -4,7 +4,6 @@ using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Maui.Handlers;
 using Microsoft.Maui.Hosting;
 using Microsoft.Maui.Hosting.Internal;
-using Microsoft.Maui.Tests;
 using Xunit;
 
 namespace Microsoft.Maui.UnitTests

src/Core/tests/UnitTests/Hosting/HostBuilderServiceBuilderTests.cs

@@ -6,7 +6,6 @@ using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.DependencyInjection.Extensions;
 using Microsoft.Extensions.Hosting;
 using Microsoft.Maui.Hosting;
-using Microsoft.Maui.Tests;
 using Xunit;
 
 namespace Microsoft.Maui.UnitTests

src/Core/tests/UnitTests/Hosting/HostBuilderServicesTests.cs

@@ -1,7 +1,6 @@
 using System;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Maui.Hosting;
-using Microsoft.Maui.Tests;
 using Xunit;
 
 namespace Microsoft.Maui.UnitTests

src/Core/tests/UnitTests/TestClasses/ApplicationStub.cs

@@ -1,4 +1,4 @@
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class ApplicationStub : IApplication
 	{

src/Core/tests/UnitTests/TestClasses/ButtonHandlerStub.cs

@@ -1,6 +1,6 @@
 using Microsoft.Maui.Handlers;
 
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class ButtonHandlerStub : ButtonHandler
 	{

src/Core/tests/UnitTests/TestClasses/ButtonStub.cs

@@ -1,6 +1,6 @@
 using Microsoft.Maui.Controls;
 
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class ButtonStub : View, IButton
 	{

src/Core/tests/UnitTests/TestClasses/HandlersContextStub.cs

@@ -1,7 +1,7 @@
 using System;
 using Microsoft.Extensions.DependencyInjection;
 
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class HandlersContextStub : IMauiContext
 	{
@@ -17,4 +17,4 @@ namespace Microsoft.Maui.Tests
 
 		public IMauiHandlersServiceProvider Handlers => _mauiHandlersServiceProvider;
 	}
-}
+}

src/Core/tests/UnitTests/TestClasses/IViewStub.cs

@@ -1,4 +1,4 @@
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	interface IViewStub : IView
 	{

src/Core/tests/UnitTests/TestClasses/InvalidHandlersContextStub.cs

@@ -0,0 +1,15 @@
+using System;
+
+namespace Microsoft.Maui.UnitTests
+{
+	class InvalidHandlersContextStub : IMauiContext
+	{
+		public InvalidHandlersContextStub()
+		{
+		}
+
+		public IServiceProvider Services => null!;
+
+		public IMauiHandlersServiceProvider Handlers => null!;
+	}
+}

src/Core/tests/UnitTests/TestClasses/NativeViewStub.cs

@@ -1,4 +1,4 @@
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class NativeViewStub
 	{

src/Core/tests/UnitTests/TestClasses/TestServices.cs

@@ -1,6 +1,6 @@
 using System.Collections.Generic;
 
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	interface IFooService
 	{

src/Core/tests/UnitTests/TestClasses/ViewHandlerStub.cs

@@ -1,5 +1,5 @@
 using Microsoft.Maui.Handlers;
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class ViewHandlerStub : ViewHandler<IViewStub, NativeViewStub>
 	{

src/Core/tests/UnitTests/TestClasses/ViewStub.cs

@@ -1,7 +1,7 @@
 using System;
 using Microsoft.Maui.Primitives;
 
-namespace Microsoft.Maui.Tests
+namespace Microsoft.Maui.UnitTests
 {
 	class ViewStub : IViewStub
 	{