[Core] Support child assignable types

5 files changed, 46 insertions, 7 deletions

diff --git a/Xamarin.PropertyEditing/AssignableTypesResult.cs b/Xamarin.PropertyEditing/AssignableTypesResult.cs
new file mode 100644
index 0000000..b16170a
--- /dev/null
+++ b/Xamarin.PropertyEditing/AssignableTypesResult.cs
@@ -0,0 +1,35 @@
+using System;
+using System.Collections.Generic;
+
+namespace Xamarin.PropertyEditing
+{
+	public class AssignableTypesResult
+	{
+		public AssignableTypesResult (IReadOnlyList<ITypeInfo> assignableTypes)
+		{
+			if (assignableTypes == null)
+				throw new ArgumentNullException (nameof(assignableTypes));
+
+			AssignableTypes = assignableTypes;
+		}
+
+		public AssignableTypesResult (IReadOnlyList<ITypeInfo> suggestedTypes, IReadOnlyList<ITypeInfo> assignableTypes)
+			: this (assignableTypes)
+		{
+			if (suggestedTypes == null)
+				throw new ArgumentNullException (nameof(suggestedTypes));
+
+			SuggestedTypes = suggestedTypes;
+		}
+
+		public IReadOnlyList<ITypeInfo> SuggestedTypes
+		{
+			get;
+		}
+
+		public IReadOnlyList<ITypeInfo> AssignableTypes
+		{
+			get;
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing/IObjectEditor.cs b/Xamarin.PropertyEditing/IObjectEditor.cs
index 9fbea05..2b53bb3 100644
--- a/Xamarin.PropertyEditing/IObjectEditor.cs
+++ b/Xamarin.PropertyEditing/IObjectEditor.cs
@@ -58,7 +58,10 @@ namespace Xamarin.PropertyEditing
 		/// </summary>
 		event EventHandler<EditorPropertyChangedEventArgs> PropertyChanged;
 
-		Task<IReadOnlyList<ITypeInfo>> GetAssignableTypesAsync (IPropertyInfo property);
+		/// <param name="property">The property to get retrieve assignable types for.</param>
+		/// <param name="childTypes">Whether or not to return assignable types for a property's children rather than the property itself.</param>
+		/// <returns>An <see cref="AssignableTypesResult"/> instance containing the assignable types. No assignable types should use an empty array and not return <c>null</c>.</returns>
+		Task<AssignableTypesResult> GetAssignableTypesAsync (IPropertyInfo property, bool childTypes);
 
 		/*
 		 * Dealing with async values in the context of what's possible across all target platforms is a bit complex.
diff --git a/Xamarin.PropertyEditing/Reflection/ReflectionObjectEditor.cs b/Xamarin.PropertyEditing/Reflection/ReflectionObjectEditor.cs
index 872d706..19b8d7d 100644
--- a/Xamarin.PropertyEditing/Reflection/ReflectionObjectEditor.cs
+++ b/Xamarin.PropertyEditing/Reflection/ReflectionObjectEditor.cs
@@ -92,19 +92,19 @@ namespace Xamarin.PropertyEditing.Reflection
 			return Task.FromResult (info.GetHandlers (this.target));
 		}
 
-		public Task<IReadOnlyList<ITypeInfo>> GetAssignableTypesAsync (IPropertyInfo property)
+		public Task<AssignableTypesResult> GetAssignableTypesAsync (IPropertyInfo property, bool childTypes)
 		{
 			return Task.Run (() => {
 				ReflectionPropertyInfo realInfo = (ReflectionPropertyInfo) property;
 				var assemblies = AppDomain.CurrentDomain.GetAssemblies ();
 				var entry = Assembly.GetEntryAssembly();
 
-				return (IReadOnlyList<ITypeInfo>)assemblies.Select (a => new { Assembly = a, Info = new AssemblyInfo (a.FullName, a == entry)})
+				return new AssignableTypesResult (assemblies.Select (a => new { Assembly = a, Info = new AssemblyInfo (a.FullName, a == entry)})
 					.SelectMany (a =>
 						a.Assembly.DefinedTypes.Select (t => new { Type = t, Assembly = a }))
 					.AsParallel ()
 					.Where (t => realInfo.Type.IsAssignableFrom (t.Type))
-					.Select (t => new TypeInfo (t.Assembly.Info, t.Type.Namespace, t.Type.Name)).ToList();
+					.Select (t => new TypeInfo (t.Assembly.Info, t.Type.Namespace, t.Type.Name)).ToList());
 			});
 		}
 
diff --git a/Xamarin.PropertyEditing/ViewModels/ObjectPropertyViewModel.cs b/Xamarin.PropertyEditing/ViewModels/ObjectPropertyViewModel.cs
index 15b454d..16f1b21 100644
--- a/Xamarin.PropertyEditing/ViewModels/ObjectPropertyViewModel.cs
+++ b/Xamarin.PropertyEditing/ViewModels/ObjectPropertyViewModel.cs
@@ -237,11 +237,11 @@ namespace Xamarin.PropertyEditing.ViewModels
 
 		private async Task<IReadOnlyDictionary<IAssemblyInfo, ILookup<string, ITypeInfo>>> GetAssignableTypesAsync ()
 		{
-			Task<IReadOnlyList<ITypeInfo>>[] typeTasks = Editors.Select (o => o.GetAssignableTypesAsync (Property)).ToArray();
-			IReadOnlyList<ITypeInfo>[] lists = await Task.WhenAll (typeTasks).ConfigureAwait (false);
+			Task<AssignableTypesResult>[] typeTasks = Editors.Select (o => o.GetAssignableTypesAsync (Property, childTypes: false)).ToArray();
+			AssignableTypesResult[] lists = await Task.WhenAll (typeTasks).ConfigureAwait (false);
 
 			var assemblies = new Dictionary<IAssemblyInfo, ILookup<string, ITypeInfo>> ();
-			foreach (ITypeInfo type in lists.SelectMany (t => t)) {
+			foreach (ITypeInfo type in lists.SelectMany (t => t.AssignableTypes)) {
 				if (!assemblies.TryGetValue (type.Assembly, out ILookup<string, ITypeInfo> types)) {
 					assemblies[type.Assembly] = types = new ObservableLookup<string, ITypeInfo> ();
 				}
diff --git a/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj b/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj
index fdc38df..be28bc8 100644
--- a/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj
+++ b/Xamarin.PropertyEditing/Xamarin.PropertyEditing.csproj
@@ -46,6 +46,7 @@
     <Reference Include="System.Xml" />
   </ItemGroup>
   <ItemGroup>
+    <Compile Include="AssignableTypesResult.cs" />
     <Compile Include="AsyncValue.cs" />
     <Compile Include="AsyncWorkQueue.cs" />
     <Compile Include="BidirectionalDictionary.cs" />