Added xaml parser support for collections in attached properties.

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/XamlDom/ExampleService.cs

@@ -26,6 +26,22 @@ namespace ICSharpCode.WpfDesign.Tests.XamlDom
 			TestHelperLog.Log("ExampleService.SetExample");
 			element.SetValue(ExampleProperty, value);
 		}
+		
+		public static readonly DependencyProperty ExampleCollectionProperty = DependencyProperty.RegisterAttached(
+			"ExampleCollection", typeof(ExampleClassList), typeof(ExampleService)
+		);
+		
+		public static ExampleClassList GetExampleCollection(DependencyObject element)
+		{
+			TestHelperLog.Log("ExampleService.GetExampleCollection");
+			return (ExampleClassList)element.GetValue(ExampleCollectionProperty);
+		}
+		
+		public static void SetExampleCollection(DependencyObject element, ExampleClassList value)
+		{
+			TestHelperLog.Log("ExampleService.SetExampleCollection");
+			element.SetValue(ExampleCollectionProperty, value);
+		}
 	}
 	
 	public class ExampleDependencyObject : DependencyObject

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Tests/XamlDom/SimpleLoadTests.cs

@@ -221,6 +221,25 @@ namespace ICSharpCode.WpfDesign.Tests.XamlDom
 			");
 		}
 		
+		[Test]
+		public void ExampleServiceCollectionTest()
+		{
+			TestLoading(@"
+<t:ExampleDependencyObject
+  xmlns=""http://schemas.microsoft.com/netfx/2007/xaml/presentation""
+  xmlns:t=""" + XamlTypeFinderTests.XamlDomTestsNamespace + @"""
+  xmlns:x=""http://schemas.microsoft.com/winfx/2006/xaml"">
+   <t:ExampleService.ExampleCollection>
+      <t:ExampleClassList>
+         <t:ExampleClass OtherProp=""a""> </t:ExampleClass>
+         <t:ExampleClass OtherProp=""b"" />
+         <t:ExampleClass OtherProp=""c"" />
+      </t:ExampleClassList>
+   </t:ExampleService.ExampleCollection>
+</t:ExampleDependencyObject>
+			");
+		}
+		
 		[Test]
 		public void ExampleClassObjectPropWithStringValue()
 		{

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.XamlDom/Project/XamlProperty.cs

@@ -278,14 +278,20 @@ namespace ICSharpCode.WpfDesign.XamlDom
 
 		XmlElement CreatePropertyElement()
 		{
-            string ns = parentObject.OwnerDocument.GetNamespaceFor(parentObject.ElementType);
+			Type propertyElementType = GetPropertyElementType();
+			string ns = parentObject.OwnerDocument.GetNamespaceFor(propertyElementType);
 			return parentObject.OwnerDocument.XmlDocument.CreateElement(
 				parentObject.OwnerDocument.GetPrefixForNamespace(ns),
-                parentObject.ElementType.Name + "." + this.PropertyName,
+				propertyElementType.Name + "." + this.PropertyName,
 				ns
 			);
 		}
 
+		Type GetPropertyElementType()
+		{
+			return this.IsAttached ? this.PropertyTargetType : parentObject.ElementType;
+		}
+		
 		static XmlNode FindChildNode(XmlNode node, string localName, string namespaceURI)
 		{
 			foreach (XmlNode childNode in node.ChildNodes) {
@@ -305,7 +311,8 @@ namespace ICSharpCode.WpfDesign.XamlDom
 		{
 			if (this.IsCollection) {
 				if (IsNodeCollectionForThisProperty(newChildNode)) {
-					XmlNode parentNode = FindChildNode(parentObject.XmlElement, parentObject.ElementType.Name + "." + this.PropertyName, parentObject.OwnerDocument.GetNamespaceFor(parentObject.ElementType));
+					Type propertyElementType = GetPropertyElementType();
+					XmlNode parentNode = FindChildNode(parentObject.XmlElement, propertyElementType.Name + "." + this.PropertyName, parentObject.OwnerDocument.GetNamespaceFor(propertyElementType));
 
 					if (parentNode == null) {
 						parentNode = CreatePropertyElement();

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.XamlDom/Project/XamlPropertyInfo.cs

@@ -39,6 +39,7 @@ namespace ICSharpCode.WpfDesign.XamlDom
 	{
 		readonly DependencyProperty property;
 		readonly bool isAttached;
+		readonly bool isCollection;
 
 		public override DependencyProperty DependencyProperty {
 			get { return property; }
@@ -49,6 +50,7 @@ namespace ICSharpCode.WpfDesign.XamlDom
 			Debug.Assert(property != null);
 			this.property = property;
 			this.isAttached = isAttached;
+			this.isCollection = CollectionSupport.IsCollectionType(property.PropertyType);
 		}
 		
 		public override TypeConverter TypeConverter {
@@ -84,7 +86,9 @@ namespace ICSharpCode.WpfDesign.XamlDom
 		}
 		
 		public override bool IsCollection {
-			get { return false; }
+			get {
+				return isCollection;
+			}
 		}
 		
 		public override object GetValue(object instance)