Added new style resource test.

To get style resources working, OmniXaml #84 really needs to be set, so
style resource tests failing for the moment.

src/Markup/Perspex.Markup.Xaml/Data/StyleResourceBinding.cs

@@ -5,6 +5,7 @@ using System;
 using System.Reactive.Disposables;
 using System.Reactive.Linq;
 using System.Reactive.Subjects;
+using Perspex.Controls;
 using Perspex.Data;
 using Perspex.Styling;
 
@@ -38,18 +39,20 @@ namespace Perspex.Markup.Xaml.Data
             PerspexProperty targetProperty,
             IPerspexObject treeAnchor = null)
         {
-            return new Subject(target, Name);
+            return new Subject(target, Name, treeAnchor);
         }
 
         private class Subject : ISubject<object>
         {
             private IPerspexObject _target;
             private string _name;
+            private IPerspexObject _treeAnchor;
 
-            public Subject(IPerspexObject target, string name)
+            public Subject(IPerspexObject target, string name, IPerspexObject treeAnchor)
             {
                 _target = target;
                 _name = name;
+                _treeAnchor = treeAnchor;
             }
 
             public void OnCompleted()
@@ -66,24 +69,25 @@ namespace Perspex.Markup.Xaml.Data
 
             public IDisposable Subscribe(IObserver<object> observer)
             {
-                // HACK around OmniXAML issue #84.
+                var host = (_target as IControl) ?? (_treeAnchor as IControl);
-                var po = (PerspexObject)_target;
+
-                var parent = PerspexPropertyRegistry.Instance.FindRegistered(po, "Parent");
+                if (host != null)
-
+                {
-                return po.GetObservable(parent)
+                    var resource = host.FindStyleResource(_name);
-                    .Where(x => x != PerspexProperty.UnsetValue && x != null)
+
-                    .Take(1)
+                    if (resource != PerspexProperty.UnsetValue)
-                    .Subscribe(_ =>
                     {
-                        var resource = ((IStyleHost)_target).FindStyleResource(_name);
+                        observer.OnNext(resource);
+                    }
 
-                        if (resource != PerspexProperty.UnsetValue)
+                    observer.OnCompleted();
-                        {
+                }
-                            observer.OnNext(resource);
+                else
-                        }
+                {
+                    // TODO: Log error.
+                }
 
-                        observer.OnCompleted();
+                return Disposable.Empty;
-                    });
             }
         }
     }

tests/Perspex.Markup.Xaml.UnitTests/Xaml/StyleTests.cs

@@ -113,5 +113,32 @@ namespace Perspex.Markup.Xaml.UnitTests.Xaml
                 Assert.Equal(0xff506070, brush.Color.ToUint32());
             }
         }
+
+        [Fact]
+        public void StyleResource_Can_Be_Assigned_To_StyleResource_Property()
+        {
+            using (UnitTestApplication.Start(TestServices.StyledWindow))
+            {
+                var xaml = @"
+<Window xmlns='https://github.com/perspex'
+        xmlns:mut='https://github.com/perspex/mutable'
+        xmlns:x='http://schemas.microsoft.com/winfx/2006/xaml'>
+    <Window.Styles>
+        <Style>
+            <Style.Resources>
+                <Color x:Key='color'>#ff506070</Color>
+                <mut:SolidColorBrush x:Key='brush' Color='{StyleResource color}'/>
+            </Style.Resources>
+        </Style>
+    </Window.Styles>
+</Window>";
+
+                var loader = new PerspexXamlLoader();
+                var window = (Window)loader.Load(xaml);
+                var brush = (Perspex.Media.Mutable.SolidColorBrush)window.FindStyleResource("brush");
+
+                Assert.Equal(0xff506070, brush.Color.ToUint32());
+            }
+        }
     }
 }