Fixed applying control templates.

And added unit tests for it.

Perspex.Controls/Presenters/ContentPresenter.cs

@@ -125,14 +125,6 @@ namespace Perspex.Controls.Presenters
                     ((ISetLogicalParent)result).SetParent(this.logicalParent ?? this);
                 }
 
-                var templatedParent = this.TemplatedParent as TemplatedControl;
-
-                if (templatedParent != null)
-                {
-                    templatedParent = templatedParent.TemplatedParent as TemplatedControl;
-                }
-
-                ((Control)result).TemplatedParent = templatedParent;
                 this.AddVisualChild(result);
                 this.LogicalChildren.Add(result);
             }

Perspex.Controls/Presenters/ItemsPresenter.cs

@@ -139,7 +139,7 @@ namespace Perspex.Controls.Presenters
         {
             this.ClearVisualChildren();
             this.Panel = this.ItemsPanel.Build();
-            this.Panel.TemplatedParent = this;
+            this.Panel.SetValue(TemplatedParentProperty, this.TemplatedParent);
             KeyboardNavigation.SetTabNavigation(this.Panel, KeyboardNavigation.GetTabNavigation(this));
             this.AddVisualChild(this.Panel);
             this.createdPanel = true;

Perspex.Controls/Primitives/TemplatedControl.cs

@@ -198,15 +198,9 @@ namespace Perspex.Controls.Primitives
                     this.templateLog.Verbose("Creating control template");
 
                     var child = this.Template.Build(this);
-                    this.SetTemplatedParent((Control)child);
+                    this.SetTemplatedParentAndApplyChildTemplates(child);
                     this.AddVisualChild((Visual)child);
                     ((ISetLogicalParent)child).SetParent(this);
-
-                    foreach (var i in this.GetTemplateChildren())
-                    {
-                        i.ApplyTemplate();
-                    }
-
                     this.OnTemplateApplied();
                 }
 
@@ -222,19 +216,24 @@ namespace Perspex.Controls.Primitives
         }
 
         /// <summary>
-        /// Sets the <see cref="TemplatedParent"/> property of the control and decendents until
-        /// an <see cref="IPresenter"/> is found.
+        /// Sets the TemplatedParent property for a control created from the control template and
+        /// applies the templates of nested templated controls.
         /// </summary>
         /// <param name="control">The control.</param>
-        private void SetTemplatedParent(Control control)
+        private void SetTemplatedParentAndApplyChildTemplates(IControl control)
         {
-            control.TemplatedParent = this;
+            if (control.TemplatedParent == null)
+            {
+                control.SetValue(TemplatedParentProperty, this);
+            }
+
+            control.ApplyTemplate();
 
-            if (!(control is IPresenter))
+            if (!(control is IPresenter && control.TemplatedParent == this))
             {
-                foreach (var child in control.GetVisualChildren().OfType<Control>())
+                foreach (IControl child in control.GetVisualChildren())
                 {
-                    this.SetTemplatedParent(child);
+                    this.SetTemplatedParentAndApplyChildTemplates(child);
                 }
             }
         }

Perspex.Layout/ILayoutable.cs

@@ -35,6 +35,8 @@ namespace Perspex.Layout
 
         Rect? PreviousArrange { get; }
 
+        void ApplyTemplate();
+
         void Measure(Size availableSize, bool force = false);
 
         void Arrange(Rect rect, bool force = false);

Tests/Perspex.Controls.UnitTests/ItemsControlTests.cs

@@ -19,7 +19,7 @@ namespace Perspex.Controls.UnitTests
     public class ItemsControlTests
     {
         [Fact]
-        public void Panel_Should_Have_TemplatedParent_Set_To_ItemsPresenter()
+        public void Panel_Should_Have_TemplatedParent_Set_To_ItemsControl()
         {
             var target = new ItemsControl();
 
@@ -28,9 +28,9 @@ namespace Perspex.Controls.UnitTests
             target.ApplyTemplate();
 
             var presenter = target.GetTemplateChildren().OfType<ItemsPresenter>().Single();
-            var panel = presenter.GetTemplateChildren().OfType<StackPanel>().Single();
+            var panel = target.GetTemplateChildren().OfType<StackPanel>().Single();
 
-            Assert.Equal(presenter, panel.TemplatedParent);
+            Assert.Equal(target, panel.TemplatedParent);
         }
 
         [Fact]
@@ -43,7 +43,7 @@ namespace Perspex.Controls.UnitTests
             target.ApplyTemplate();
 
             var presenter = target.GetTemplateChildren().OfType<ItemsPresenter>().Single();
-            var panel = presenter.GetTemplateChildren().OfType<StackPanel>().Single();
+            var panel = target.GetTemplateChildren().OfType<StackPanel>().Single();
             var item = (TextBlock)panel.GetVisualChildren().First();
 
             Assert.Null(item.TemplatedParent);

Tests/Perspex.Controls.UnitTests/Perspex.Controls.UnitTests.csproj

@@ -98,6 +98,7 @@
     <Compile Include="Presenters\DeckPresenterTests.cs" />
     <Compile Include="Presenters\ItemsPresenterTests.cs" />
     <Compile Include="Presenters\ScrollContentPresenterTests.cs" />
+    <Compile Include="Primitives\TemplatedControlTests.cs" />
     <Compile Include="Primitives\ScrollBarTests.cs" />
     <Compile Include="Primitives\RangeBaseTests.cs" />
     <Compile Include="Primitives\SelectingItemsControlTests_AutoSelect.cs" />

Tests/Perspex.Controls.UnitTests/Presenters/ItemsPresenterTests.cs

@@ -144,16 +144,6 @@ namespace Perspex.Controls.UnitTests.Presenters
             Assert.Equal(panel, target.Panel);
         }
 
-        [Fact]
-        public void Panel_TemplatedParent_Should_Be_Set()
-        {
-            var target = new ItemsPresenter();
-
-            target.ApplyTemplate();
-
-            Assert.Equal(target, target.Panel.TemplatedParent);
-        }
-
         [Fact]
         public void Panel_TabNavigation_Should_Be_Set_To_Once()
         {

Tests/Perspex.Controls.UnitTests/Primitives/TemplatedControlTests.cs

@@ -0,0 +1,159 @@
+// -----------------------------------------------------------------------
+// <copyright file="TemplatedControlTests.cs" company="Steven Kirk">
+// Copyright 2015 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Controls.UnitTests.Primitives
+{
+    using System;
+    using System.Linq;
+    using Collections;
+    using Perspex.Controls.Presenters;
+    using Perspex.Controls.Primitives;
+    using Perspex.Controls.Templates;
+    using Perspex.LogicalTree;
+    using Perspex.VisualTree;
+    using Xunit;
+
+    public class TemplatedControlTests
+    {
+        [Fact]
+        public void ApplyTemplate_Should_Create_Visual_Child()
+        {
+            var target = new TemplatedControl
+            {
+                Template = new ControlTemplate(_ => new Decorator
+                {
+                    Child = new Panel
+                    {
+                        Children = new Controls
+                        {
+                            new TextBlock(),
+                            new Border(),
+                        }
+                    }
+                }),
+            };
+
+            target.ApplyTemplate();
+
+            var types = target.GetVisualDescendents().Select(x => x.GetType()).ToList();
+
+            Assert.Equal(
+                new[]
+                {
+                    typeof(Decorator),
+                    typeof(Panel),
+                    typeof(TextBlock),
+                    typeof(Border)
+                },
+                types);
+            Assert.Empty(target.GetLogicalChildren());
+        }
+
+        [Fact]
+        public void Templated_Children_Should_Have_TemplatedParent_Set()
+        {
+            var target = new TemplatedControl
+            {
+                Template = new ControlTemplate(_ => new Decorator
+                {
+                    Child = new Panel
+                    {
+                        Children = new Controls
+                        {
+                            new TextBlock(),
+                            new Border(),
+                        }
+                    }
+                }),
+            };
+
+            target.ApplyTemplate();
+
+            var templatedParents = target.GetVisualDescendents()
+                .OfType<IControl>()
+                .Select(x => x.TemplatedParent)
+                .ToList();
+
+            Assert.Equal(4, templatedParents.Count);
+            Assert.True(templatedParents.All(x => x == target));
+        }
+
+        [Fact]
+        public void Nested_TemplatedControls_Should_Be_Expanded_And_Have_Correct_TemplatedParent()
+        {
+            var target = new ItemsControl
+            {
+                Template = new ControlTemplate<ItemsControl>(ItemsControlTemplate),
+                Items = new[] { "Foo", }
+            };
+
+            target.ApplyTemplate();
+
+            var scrollViewer = target.GetVisualDescendents()
+                .OfType<ScrollViewer>()
+                .Single();
+            var types = target.GetVisualDescendents()
+                .Select(x => x.GetType())
+                .ToList();
+            var templatedParents = target.GetVisualDescendents()
+                .OfType<IControl>()
+                .Select(x => x.TemplatedParent)
+                .ToList();
+
+            Assert.Equal(
+                new[]
+                {
+                    typeof(Border),
+                    typeof(ScrollViewer),
+                    typeof(ScrollContentPresenter),
+                    typeof(ItemsPresenter),
+                    typeof(StackPanel),
+                    typeof(TextBlock),
+                },
+                types);
+
+            Assert.Equal(
+                new object[]
+                {
+                    target,
+                    target,
+                    scrollViewer,
+                    target,
+                    target,
+                    null
+                },
+                templatedParents);
+        }
+
+        private static IControl ItemsControlTemplate(ItemsControl control)
+        {
+            return new Border
+            {
+                Child = new ScrollViewer
+                {
+                    Template = new ControlTemplate<ScrollViewer>(ScrollViewerTemplate),
+                    Content = new ItemsPresenter
+                    {
+                        Name = "itemsPresenter",
+                        [~ItemsPresenter.ItemsProperty] = control[~ListBox.ItemsProperty],
+                        [~ItemsPresenter.ItemsPanelProperty] = control[~ListBox.ItemsPanelProperty],
+                    }
+                }
+            };
+        }
+
+        private static Control ScrollViewerTemplate(ScrollViewer control)
+        {
+            var result = new ScrollContentPresenter
+            {
+                Name = "contentPresenter",
+                [~ScrollContentPresenter.ContentProperty] = control[~ScrollViewer.ContentProperty],
+            };
+
+            return result;
+        }
+    }
+}