Shell routing and Service registration automation

src/Controls/src/Core/MauiServiceAttribute.cs

@@ -0,0 +1,30 @@
+using System;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Microsoft.Maui.Controls
+{
+	[AttributeUsage(AttributeTargets.Class)]
+	public class MauiServiceAttribute : Attribute
+	{
+		/// <summary>
+		/// Type gets registered in the DI container, defaults to Singleton
+		/// </summary>
+		public MauiServiceAttribute(ServiceLifetime lifetime = ServiceLifetime.Singleton) => Lifetime = lifetime;
+
+		/// <summary>
+		/// Lifetime of the Service type on which this attribute is defined.
+		/// </summary>
+		public ServiceLifetime Lifetime { get; }
+
+		/// <summary>
+		/// The type for which this service would be resolved for.
+		/// <code>builder.Services.AddSingleton&lt;INavigationService, NavigationService&gt;();</code>
+		/// </summary>
+		public Type? RegisterFor { get; set; }
+
+		/// <summary>
+		/// If set to true, makes use of the TryAdd method construct while registering the service.
+		/// </summary>
+		public bool UseTryAdd { get; set; }
+	}
+}

src/Controls/src/Core/PublicAPI/netstandard/PublicAPI.Unshipped.txt

@@ -1,7 +1,26 @@
 #nullable enable
 *REMOVED*override Microsoft.Maui.Controls.RefreshView.MeasureOverride(double widthConstraint, double heightConstraint) -> Microsoft.Maui.Graphics.Size
 Microsoft.Maui.Controls.LayoutOptions.Equals(Microsoft.Maui.Controls.LayoutOptions other) -> bool
+Microsoft.Maui.Controls.MauiServiceAttribute
+Microsoft.Maui.Controls.MauiServiceAttribute.MauiServiceAttribute(Microsoft.Extensions.DependencyInjection.ServiceLifetime lifetime = Microsoft.Extensions.DependencyInjection.ServiceLifetime.Singleton) -> void
+Microsoft.Maui.Controls.MauiServiceAttribute.RegisterFor.get -> System.Type?
+Microsoft.Maui.Controls.MauiServiceAttribute.RegisterFor.set -> void
+Microsoft.Maui.Controls.MauiServiceAttribute.Lifetime.get -> Microsoft.Extensions.DependencyInjection.ServiceLifetime
+Microsoft.Maui.Controls.MauiServiceAttribute.UseTryAdd.get -> bool
+Microsoft.Maui.Controls.MauiServiceAttribute.UseTryAdd.set -> void
 Microsoft.Maui.Controls.Region.Equals(Microsoft.Maui.Controls.Region other) -> bool
+Microsoft.Maui.Controls.RouteAttribute
+Microsoft.Maui.Controls.RouteAttribute.ImplicitViewModel.get -> bool
+Microsoft.Maui.Controls.RouteAttribute.ImplicitViewModel.set -> void
+Microsoft.Maui.Controls.RouteAttribute.Route.get -> string?
+Microsoft.Maui.Controls.RouteAttribute.RouteAttribute() -> void
+Microsoft.Maui.Controls.RouteAttribute.RouteAttribute(string! route, Microsoft.Extensions.DependencyInjection.ServiceLifetime lifetime = Microsoft.Extensions.DependencyInjection.ServiceLifetime.Singleton) -> void
+Microsoft.Maui.Controls.RouteAttribute.Routes.get -> string![]?
+Microsoft.Maui.Controls.RouteAttribute.Routes.set -> void
+Microsoft.Maui.Controls.RouteAttribute.Lifetime.get -> Microsoft.Extensions.DependencyInjection.ServiceLifetime
+Microsoft.Maui.Controls.RouteAttribute.Lifetime.set -> void
+Microsoft.Maui.Controls.RouteAttribute.ViewModelType.get -> System.Type?
+Microsoft.Maui.Controls.RouteAttribute.ViewModelType.set -> void
 Microsoft.Maui.Controls.Shapes.Matrix.Equals(Microsoft.Maui.Controls.Shapes.Matrix other) -> bool
 Microsoft.Maui.Controls.VisualElement.~VisualElement() -> void
 override Microsoft.Maui.Controls.LayoutOptions.GetHashCode() -> int

src/Controls/src/Core/RouteAttribute.cs

@@ -0,0 +1,38 @@
+using System;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Microsoft.Maui.Controls
+{
+	[AttributeUsage(AttributeTargets.Class)]
+	public class RouteAttribute : Attribute
+	{
+		public RouteAttribute() { }
+
+		public RouteAttribute(string route, ServiceLifetime lifetime = ServiceLifetime.Singleton)
+			=> (Route, Lifetime) = (route, lifetime);
+
+		public string? Route { get; }
+
+		/// <summary>
+		/// Routes of the View (page) type on which this attribute is defined.
+		/// When both Routes and Route properties are defined, Routes takes precedence.
+		/// </summary>
+		public string[]? Routes { get; set; }
+
+		/// <summary>
+		/// Lifetime of the View (page) / ViewModel type on which this attribute is defined.
+		/// </summary>
+		public ServiceLifetime Lifetime { get; set; }
+
+		/// <summary>
+		/// Indicates whether the ViewModel should be associated automatically.
+		/// </summary>
+		public bool ImplicitViewModel { get; set; }
+
+		/// <summary>
+		/// Type of the ViewModel associated with the View (page) on which this attribute is defined.
+		/// When both ImplicitViewModel and ViewModelType properties are defined, ViewModelType takes precedence.
+		/// </summary>
+		public Type? ViewModelType { get; set; }
+	}
+}

src/Controls/src/SourceGen/Helper.cs

@@ -0,0 +1,52 @@
+using Microsoft.CodeAnalysis;
+using Microsoft.CodeAnalysis.CSharp.Syntax;
+
+namespace Microsoft.Maui.Controls.SourceGen
+{
+	internal static class Helper
+	{
+		internal const string Singleton = nameof(Singleton);
+		internal const string Scoped = nameof(Scoped);
+		internal const string Transient = nameof(Transient);
+
+		// Determine the namespace the class/enum/struct/record is declared in, if any
+		internal static string GetNamespace(BaseTypeDeclarationSyntax syntax)
+		{
+			// If we don't have a namespace at all we'll return an empty string
+			// This accounts for the "default namespace" case
+			string @namespace = string.Empty;
+
+			// Get the containing syntax node for the type declaration
+			// (could be a nested type, for example)
+			SyntaxNode? potentialNamespaceParent = syntax.Parent;
+
+			// Keep moving "out" of nested classes etc until we get to a namespace
+			// or until we run out of parents
+			while (potentialNamespaceParent is not null
+				&& potentialNamespaceParent is not NamespaceDeclarationSyntax
+				&& potentialNamespaceParent is not FileScopedNamespaceDeclarationSyntax)
+			{
+				potentialNamespaceParent = potentialNamespaceParent.Parent;
+			}
+
+			// Build up the final namespace by looping until we no longer have a namespace declaration
+			if (potentialNamespaceParent is BaseNamespaceDeclarationSyntax namespaceParent)
+			{
+				// We have a namespace. Use that as the type
+				@namespace = namespaceParent.Name.ToString();
+
+				// Keep moving "out" of the namespace declarations until we 
+				// run out of nested namespace declarations
+				while (namespaceParent.Parent is NamespaceDeclarationSyntax parent)
+				{
+					// Add the outer namespace as a prefix to the final namespace
+					@namespace = $"{parent.Name}.{@namespace}";
+					namespaceParent = parent;
+				}
+			}
+
+			// return the final namespace
+			return @namespace;
+		}
+	}
+}