[Xaml] Set the TargetProperty on ServiceProvider (#847)

Xamarin.Forms.Core.UnitTests/BaseTestFixture.cs

@@ -11,6 +11,8 @@ namespace Xamarin.Forms.Core.UnitTests
 		[SetUp]
 		public virtual void Setup ()
 		{
+			Device.PlatformServices = new MockPlatformServices();
+
 #if !WINDOWS_PHONE
 			var culture = Environment.GetEnvironmentVariable ("UNIT_TEST_CULTURE");
 			
@@ -24,7 +26,7 @@ namespace Xamarin.Forms.Core.UnitTests
 		[TearDown]
 		public virtual void TearDown ()
 		{
-			
+			Device.PlatformServices = null;
 		}
 	}
 }

Xamarin.Forms.Xaml.UnitTests/Issues/Bz53275.xaml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<ContentPage xmlns="http://xamarin.com/schemas/2014/forms"
+	xmlns:x="http://schemas.microsoft.com/winfx/2009/xaml"
+	xmlns:local="clr-namespace:Xamarin.Forms.Xaml.UnitTests"
+	x:Class="Xamarin.Forms.Xaml.UnitTests.Bz53275"
+	ANonBindableProperty="{local:TargetProperty}">
+	<Label x:Name="label" Text="{local:TargetProperty}" />
+</ContentPage>

Xamarin.Forms.Xaml.UnitTests/Issues/Bz53275.xaml.cs

@@ -0,0 +1,57 @@
+using System;
+using System.Reflection;
+using NUnit.Framework;
+using Xamarin.Forms.Core.UnitTests;
+
+namespace Xamarin.Forms.Xaml.UnitTests
+{
+	public class TargetPropertyExtension : IMarkupExtension
+	{
+		public object ProvideValue(IServiceProvider serviceProvider)
+		{
+			var targetProperty = (serviceProvider?.GetService(typeof(IProvideValueTarget)) as IProvideValueTarget)?.TargetProperty;
+			return (targetProperty as BindableProperty)?.PropertyName ?? (targetProperty as PropertyInfo)?.Name;
+		}
+	}
+
+	public partial class Bz53275 : ContentPage
+	{
+		public Bz53275()
+		{
+			InitializeComponent();
+		}
+
+		public Bz53275(bool useCompiledXaml)
+		{
+			//this stub will be replaced at compile time
+		}
+
+		public string ANonBindableProperty { get; set; }
+
+		[TestFixture]
+		class Tests
+		{
+			[SetUp]
+			public void Setup()
+			{
+				Device.PlatformServices = new MockPlatformServices();
+			}
+
+			[TearDown]
+			public void TearDown()
+			{
+				Device.PlatformServices = null;
+			}
+
+			[TestCase(true)]
+			[TestCase(false)]
+			public void TargetPropertyIsSetOnMarkups(bool useCompiledXaml)
+			{
+				var page = new Bz53275(useCompiledXaml);
+				Assert.AreEqual("ANonBindableProperty", page.ANonBindableProperty);
+				var l0 = page.label;
+				Assert.AreEqual("Text", l0.Text);
+			}
+		}
+	}
+}

Xamarin.Forms.Xaml.UnitTests/TypeExtension.xaml.cs

@@ -3,6 +3,7 @@ using System.Collections.Generic;
 using System.Windows.Input;
 using Xamarin.Forms;
 using NUnit.Framework;
+using Xamarin.Forms.Core.UnitTests;
 
 namespace Xamarin.Forms.Xaml.UnitTests
 {
@@ -46,6 +47,18 @@ namespace Xamarin.Forms.Xaml.UnitTests
 		[TestFixture]
 		public class Tests
 		{
+			[SetUp]
+			public void Setup()
+			{
+				Device.PlatformServices = new MockPlatformServices();
+			}
+
+			[TearDown]
+			public void TearDown()
+			{
+				Device.PlatformServices = null;
+			}
+
 			[TestCase(false)]
 			[TestCase(true)]
 			public void NestedMarkupExtensionInsideDataTemplate(bool useCompiledXaml)

Xamarin.Forms.Xaml.UnitTests/Xamarin.Forms.Xaml.UnitTests.csproj

@@ -470,6 +470,9 @@
     <Compile Include="Issues\Bz41048.xaml.cs">
       <DependentUpon>Bz41048.xaml</DependentUpon>
     </Compile>
+    <Compile Include="Issues\Bz53275.xaml.cs">
+      <DependentUpon>Bz53275.xaml</DependentUpon>
+    </Compile>
   </ItemGroup>
   <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />
   <Import Project="..\.nuspec\Xamarin.Forms.Debug.targets" />
@@ -860,6 +863,9 @@
     <EmbeddedResource Include="Issues\Bz41048.xaml">
       <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
     </EmbeddedResource>
+    <EmbeddedResource Include="Issues\Bz53275.xaml">
+      <Generator>MSBuild:UpdateDesignTimeXaml</Generator>
+    </EmbeddedResource>
   </ItemGroup>
   <ItemGroup>
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />

Xamarin.Forms.Xaml/ApplyPropertiesVisitor.cs

@@ -77,7 +77,8 @@ namespace Xamarin.Forms.Xaml
 		public void Visit(ElementNode node, INode parentNode)
 		{
 			var propertyName = XmlName.Empty;
-			if (TryGetPropertyName(node, parentNode, out propertyName) && propertyName == XmlName._CreateContent){
+
+			if (TryGetPropertyName(node, parentNode, out propertyName) && propertyName == XmlName._CreateContent) {
 				var s0 = Values[parentNode];
 				if (s0 is ElementTemplate) {
 					SetTemplate(s0 as ElementTemplate, node);
@@ -85,21 +86,7 @@ namespace Xamarin.Forms.Xaml
 				}
 			}
 
-			var value = Values [node];
 			var parentElement = parentNode as IElementNode;
-			var markupExtension = value as IMarkupExtension;
-			var valueProvider = value as IValueProvider;
-
-			if (markupExtension != null) {
-				var serviceProvider = value.GetType().GetTypeInfo().GetCustomAttribute<AcceptEmptyServiceProviderAttribute>() == null ? new XamlServiceProvider(node, Context) : null;
-				value = markupExtension.ProvideValue(serviceProvider);
-			}
-
-			if (valueProvider != null) {
-				var serviceProvider = value.GetType().GetTypeInfo().GetCustomAttribute<AcceptEmptyServiceProviderAttribute>() == null ? new XamlServiceProvider(node, Context) : null;
-				value = valueProvider.ProvideValue(serviceProvider);
-			}
-
 			propertyName = XmlName.Empty;
 
 			//Simplify ListNodes with single elements
@@ -110,6 +97,15 @@ namespace Xamarin.Forms.Xaml
 				parentElement = parentNode as IElementNode;
 			}
 
+			var value = Values[node];
+
+			var markupExtension = value as IMarkupExtension;
+			var valueProvider = value as IValueProvider;
+			XamlServiceProvider serviceProvider = null;
+			if (markupExtension != null || valueProvider != null)
+				serviceProvider = value.GetType().GetTypeInfo().GetCustomAttribute<AcceptEmptyServiceProviderAttribute>() == null ? new XamlServiceProvider(node, Context) : null;
+
+
 			if (propertyName != XmlName.Empty || TryGetPropertyName(node, parentNode, out propertyName)) {
 				if (Skips.Contains(propertyName))
 					return;
@@ -117,8 +113,21 @@ namespace Xamarin.Forms.Xaml
 					return;
 
 				var source = Values [parentNode];
+				if (serviceProvider != null)
+					((XamlValueTargetProvider)serviceProvider.IProvideValueTarget).TargetProperty = GetTargetProperty(source, propertyName, Context, node);
+
+				if (markupExtension != null)
+					value = markupExtension.ProvideValue(serviceProvider);
+				else if (valueProvider != null)
+					value = valueProvider.ProvideValue(serviceProvider);
+
 				SetPropertyValue(source, propertyName, value, Context.RootElement, node, Context, node);
 			} else if (IsCollectionItem(node, parentNode) && parentNode is IElementNode) {
+				if (markupExtension != null)
+					value = markupExtension.ProvideValue(serviceProvider);
+				else if (valueProvider != null)
+					value = valueProvider.ProvideValue(serviceProvider);
+
 				// Collection element, implicit content, or implicit collection element.
 				string contentProperty;
 				if (typeof(IEnumerable).GetTypeInfo().IsAssignableFrom(Context.Types [parentElement].GetTypeInfo()) && Context.Types[parentElement].GetRuntimeMethods().Any(mi => mi.Name == "Add" && mi.GetParameters().Length == 1)) {
@@ -140,6 +149,11 @@ namespace Xamarin.Forms.Xaml
 				} else
 					throw new XamlParseException($"Can not set the content of {((IElementNode)parentNode).XmlType.Name} as it doesn't have a ContentPropertyAttribute", node);
 			} else if (IsCollectionItem(node, parentNode) && parentNode is ListNode) {
+				if (markupExtension != null)
+					value = markupExtension.ProvideValue(serviceProvider);
+				else if (valueProvider != null)
+					value = valueProvider.ProvideValue(serviceProvider);
+
 				var parentList = (ListNode)parentNode;
 				var source = Values [parentNode.Parent];
 
@@ -269,6 +283,22 @@ namespace Xamarin.Forms.Xaml
 			return null;
 		}
 
+		static object GetTargetProperty(object xamlelement, XmlName propertyName, HydratationContext context, IXmlLineInfo lineInfo)
+		{
+			var localName = propertyName.LocalName;
+			//If it's an attached BP, update elementType and propertyName
+			var bpOwnerType = xamlelement.GetType();
+			GetRealNameAndType(ref bpOwnerType, propertyName.NamespaceURI, ref localName, context, lineInfo);
+			var property = GetBindableProperty(bpOwnerType, localName, lineInfo, false);
+
+			if (property != null)
+				return property;
+			
+			var elementType = xamlelement.GetType();
+			var propertyInfo = elementType.GetRuntimeProperties().FirstOrDefault(p => p.Name == localName);
+			return propertyInfo;
+		}
+
 		public static void SetPropertyValue(object xamlelement, XmlName propertyName, object value, object rootElement, INode node, HydratationContext context, IXmlLineInfo lineInfo)
 		{
 			var localName = propertyName.LocalName;
@@ -397,6 +427,9 @@ namespace Xamarin.Forms.Xaml
 			if (property == null)
 				return false;
 
+			if (serviceProvider != null && serviceProvider.IProvideValueTarget != null)
+				((XamlValueTargetProvider)serviceProvider.IProvideValueTarget).TargetProperty = property;
+
 			Func<MemberInfo> minforetriever;
 			if (attached)
 				minforetriever = () => property.DeclaringType.GetRuntimeMethod("Get" + property.PropertyName, new [] { typeof(BindableObject) });
@@ -436,6 +469,9 @@ namespace Xamarin.Forms.Xaml
 			if (!IsVisibleFrom(setter, context.RootElement))
 				return false;
 
+			if (serviceProvider != null && serviceProvider.IProvideValueTarget != null)
+				((XamlValueTargetProvider)serviceProvider.IProvideValueTarget).TargetProperty = propertyInfo;
+
 			object convertedValue = value.ConvertTo(propertyInfo.PropertyType, () => propertyInfo, serviceProvider);
 			if (convertedValue != null && !propertyInfo.PropertyType.IsInstanceOfType(convertedValue))
 				return false;
@@ -475,6 +511,7 @@ namespace Xamarin.Forms.Xaml
 			if (addMethod == null)
 				return false;
 
+			((XamlValueTargetProvider)serviceProvider.IProvideValueTarget).TargetProperty = propertyInfo;
 			addMethod.Invoke(collection, new [] { value.ConvertTo(addMethod.GetParameters() [0].ParameterType, (Func<TypeConverter>)null, serviceProvider) });
 			return true;
 		}

Xamarin.Forms.Xaml/XamlServiceProvider.cs

@@ -103,7 +103,7 @@ namespace Xamarin.Forms.Xaml.Internals
 
 		HydratationContext Context { get; }
 		public object TargetObject { get; }
-		public object TargetProperty { get; } = null;
+		public object TargetProperty { get; internal set; } = null;
 
 		IEnumerable<object> IProvideParentValues.ParentObjects
 		{