Implemented NameScopes

Some tests still failing as controls are only registered with name scope
when attached to a rooted visual tree. Need to work around this by
explicitly registering controls when applying template.

src/Perspex.Controls/Button.cs

@@ -147,13 +147,13 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
 
             if (IsDefault)
             {
-                var inputElement = root as IInputElement;
+                var inputElement = e.Root as IInputElement;
 
                 if (inputElement != null)
                 {
@@ -198,13 +198,13 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnDetachedFromVisualTree(IRenderRoot oldRoot)
+        protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnDetachedFromVisualTree(oldRoot);
+            base.OnDetachedFromVisualTree(e);
 
             if (IsDefault)
             {
-                var inputElement = oldRoot as IInputElement;
+                var inputElement = e.Root as IInputElement;
 
                 if (inputElement != null)
                 {

src/Perspex.Controls/Carousel.cs

@@ -55,11 +55,5 @@ namespace Perspex.Controls
         {
             // Ignore pointer presses.
         }
-
-        /// <inheritdoc/>
-        protected override void OnTemplateApplied()
-        {
-            base.OnTemplateApplied();
-        }
     }
 }

src/Perspex.Controls/ContentControl.cs

@@ -104,12 +104,12 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
             // We allow ContentControls without ContentPresenters in the template. This can be
             // useful for e.g. a simple ToggleButton that displays an image. There's no need to
             // have a ContentPresenter in the visual tree for that.
-            Presenter = this.FindTemplateChild<ContentPresenter>("PART_ContentPresenter");
+            Presenter = nameScope.Find<ContentPresenter>("PART_ContentPresenter");
         }
     }
 }

src/Perspex.Controls/Control.cs

@@ -19,7 +19,6 @@ namespace Perspex.Controls
     /// <remarks>
     /// The control class extends <see cref="InputElement"/> and adds the following features:
     ///
-    /// - A <see cref="Name"/>.
     /// - An inherited <see cref="DataContext"/>.
     /// - A <see cref="Tag"/> property to allow user-defined data to be attached to the control.
     /// - A collection of class strings for custom styling.
@@ -71,7 +70,6 @@ namespace Perspex.Controls
         private readonly Classes _classes = new Classes();
         private DataTemplates _dataTemplates;
         private IControl _focusAdorner;
-        private string _name;
         private IPerspexList<ILogical> _logicalChildren;
         private Styles _styles;
 
@@ -165,36 +163,6 @@ namespace Perspex.Controls
             }
         }
 
-        /// <summary>
-        /// Gets or sets the name of the control.
-        /// </summary>
-        /// <remarks>
-        /// A control's name is used to uniquely identify a control within the control's name
-        /// scope. Once a control is added to a visual tree, its name cannot be changed.
-        /// </remarks>
-        public string Name
-        {
-            get
-            {
-                return _name;
-            }
-
-            set
-            {
-                if (_name != null)
-                {
-                    throw new InvalidOperationException("Name already set.");
-                }
-
-                if (((IVisual)this).VisualParent != null)
-                {
-                    throw new InvalidOperationException("Cannot set Name : control already added to tree.");
-                }
-
-                _name = value;
-            }
-        }
-
         /// <summary>
         /// Gets or sets the styles for the control.
         /// </summary>
@@ -404,9 +372,9 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
 
             IStyler styler = PerspexLocator.Current.GetService<IStyler>();
 

src/Perspex.Controls/DropDown.cs

@@ -125,14 +125,14 @@ namespace Perspex.Controls
             base.OnPointerPressed(e);
         }
 
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
             if (_popup != null)
             {
                 _popup.Opened -= PopupOpened;
             }
 
-            _popup = this.GetTemplateChild<Popup>("PART_Popup");
+            _popup = nameScope.Get<Popup>("PART_Popup");
             _popup.Opened += PopupOpened;
         }
 

src/Perspex.Controls/GridSplitter.cs

@@ -34,9 +34,9 @@ namespace Perspex.Controls
             }
         }
 
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
             _grid = this.GetVisualParent<Grid>();
         }
     }

src/Perspex.Controls/ItemsControl.cs

@@ -147,9 +147,9 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
-            Presenter = this.FindTemplateChild<IItemsPresenter>("PART_ItemsPresenter");
+            Presenter = nameScope.Find<IItemsPresenter>("PART_ItemsPresenter");
         }
 
         /// <summary>

src/Perspex.Controls/Menu.cs

@@ -96,15 +96,12 @@ namespace Perspex.Controls
             IsOpen = true;
         }
 
-        /// <summary>
-        /// Called when the <see cref="MenuItem"/> is attached to the visual tree.
-        /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        /// <inheritdoc/>
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
 
-            var topLevel = root as TopLevel;
+            var topLevel = e.Root as TopLevel;
 
             topLevel.Deactivated += Deactivated;
 
@@ -117,7 +114,7 @@ namespace Perspex.Controls
                 pointerPress,
                 Disposable.Create(() => topLevel.Deactivated -= Deactivated));
 
-            var inputRoot = root as IInputRoot;
+            var inputRoot = e.Root as IInputRoot;
 
             if (inputRoot != null && inputRoot.AccessKeyHandler != null)
             {
@@ -125,13 +122,10 @@ namespace Perspex.Controls
             }
         }
 
-        /// <summary>
-        /// Called when the <see cref="Menu"/> is detached from the visual tree.
-        /// </summary>
-        /// <param name="oldRoot">The root of the visual tree being detached from.</param>
-        protected override void OnDetachedFromVisualTree(IRenderRoot oldRoot)
+        /// <inheritdoc/>
+        protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnDetachedFromVisualTree(oldRoot);
+            base.OnDetachedFromVisualTree(e);
             _subscription.Dispose();
         }
 

src/Perspex.Controls/MenuItem.cs

@@ -376,11 +376,11 @@ namespace Perspex.Controls
         /// <summary>
         /// Called when the MenuItem's template has been applied.
         /// </summary>
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
-            base.OnTemplateApplied();
+            base.OnTemplateApplied(nameScope);
 
-            _popup = this.GetTemplateChild<Popup>("PART_Popup");
+            _popup = nameScope.Get<Popup>("PART_Popup");
             _popup.DependencyResolver = DependencyResolver.Instance;
             _popup.PopupRootCreated += PopupRootCreated;
             _popup.Opened += PopupOpened;

src/Perspex.Controls/Primitives/AccessText.cs

@@ -108,14 +108,11 @@ namespace Perspex.Controls.Primitives
             return result.WithHeight(result.Height + 1);
         }
 
-        /// <summary>
-        /// Called when the control is attached to a visual tree.
-        /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        /// <inheritdoc/>
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
-            _accessKeys = (root as IInputRoot)?.AccessKeyHandler;
+            base.OnAttachedToVisualTree(e);
+            _accessKeys = (e.Root as IInputRoot)?.AccessKeyHandler;
 
             if (_accessKeys != null && AccessKey != 0)
             {
@@ -123,13 +120,10 @@ namespace Perspex.Controls.Primitives
             }
         }
 
-        /// <summary>
-        /// Called when the control is detached from a visual tree.
-        /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        protected override void OnDetachedFromVisualTree(IRenderRoot root)
+        /// <inheritdoc/>
+        protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnDetachedFromVisualTree(root);
+            base.OnDetachedFromVisualTree(e);
 
             if (_accessKeys != null && AccessKey != 0)
             {

src/Perspex.Controls/Primitives/Popup.cs

@@ -212,23 +212,17 @@ namespace Perspex.Controls.Primitives
             return new Size();
         }
 
-        /// <summary>
-        /// Called when the control is added to the visual tree.
-        /// </summary>
-        /// <param name="root">THe root of the visual tree.</param>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        /// <inheritdoc/>
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
-            _topLevel = root as TopLevel;
+            base.OnAttachedToVisualTree(e);
+            _topLevel = e.Root as TopLevel;
         }
 
-        /// <summary>
-        /// Called when the control is removed to the visual tree.
-        /// </summary>
-        /// <param name="root">THe root of the visual tree.</param>
-        protected override void OnDetachedFromVisualTree(IRenderRoot root)
+        /// <inheritdoc/>
+        protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnDetachedFromVisualTree(root);
+            base.OnDetachedFromVisualTree(e);
             _topLevel = null;
         }
 

src/Perspex.Controls/Primitives/PopupRoot.cs

@@ -93,9 +93,9 @@ namespace Perspex.Controls.Primitives
         }
 
         /// <inheritdoc/>
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
-            base.OnTemplateApplied();
+            base.OnTemplateApplied(nameScope);
 
             if (Parent.TemplatedParent != null)
             {

src/Perspex.Controls/Primitives/TemplatedControl.cs

@@ -195,6 +195,8 @@ namespace Perspex.Controls.Primitives
                     _templateLog.Verbose("Creating control template");
 
                     var child = Template.Build(this);
+                    var nameScope = new NameScope();
+                    NameScope.SetNameScope((Visual)child, nameScope);
 
                     // We need to call SetTemplatedParentAndApplyChildTemplates twice - once
                     // before the controls are added to the visual tree so that the logical
@@ -207,7 +209,7 @@ namespace Perspex.Controls.Primitives
                     AddVisualChild((Visual)child);
                     SetTemplatedParentAndApplyChildTemplates(child);
 
-                    OnTemplateApplied();
+                    OnTemplateApplied(nameScope);
                 }
 
                 _templateApplied = true;
@@ -217,7 +219,8 @@ namespace Perspex.Controls.Primitives
         /// <summary>
         /// Called when the control's template is applied.
         /// </summary>
-        protected virtual void OnTemplateApplied()
+        /// <param name="nameScope">The template name scope.</param>
+        protected virtual void OnTemplateApplied(INameScope nameScope)
         {
         }
 

src/Perspex.Controls/ProgressBar.cs

@@ -26,9 +26,9 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
-            _indicator = this.GetTemplateChild<Border>("PART_Indicator");
+            _indicator = nameScope.Get<Border>("PART_Indicator");
             UpdateIndicator(Bounds.Size);
         }
 

src/Perspex.Controls/Templates/TemplateExtensions.cs

@@ -41,27 +41,6 @@ namespace Perspex.Controls.Templates
             return null;
         }
 
-        public static T FindTemplateChild<T>(this ITemplatedControl control, string name) where T : INamed
-        {
-            return control.GetTemplateChildren().OfType<T>().SingleOrDefault(x => x.Name == name);
-        }
-
-        public static T GetTemplateChild<T>(this ITemplatedControl control, string name) where T : INamed
-        {
-            var result = control.FindTemplateChild<T>(name);
-
-            if (result == null)
-            {
-                throw new InvalidOperationException(string.Format(
-                    "Could not find template child '{0}' of type '{1}' in template for '{2}'.",
-                    name,
-                    typeof(T).FullName,
-                    control.GetType().FullName));
-            }
-
-            return result;
-        }
-
         public static IEnumerable<Control> GetTemplateChildren(this ITemplatedControl control)
         {
             var visual = control as IVisual;

src/Perspex.Controls/TextBox.cs

@@ -136,9 +136,9 @@ namespace Perspex.Controls
             set { SetValue(TextWrappingProperty, value); }
         }
 
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
-            _presenter = this.GetTemplateChild<TextPresenter>("PART_TextPresenter");
+            _presenter = nameScope.Get<TextPresenter>("PART_TextPresenter");
             _presenter.Cursor = new Cursor(StandardCursorType.Ibeam);
         }
 

src/Perspex.Controls/TopLevel.cs

@@ -287,9 +287,9 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
 
             throw new InvalidOperationException(
                 $"Control '{GetType().Name}' is a top level control and cannot be added as a child.");

src/Perspex.Controls/TreeViewItem.cs

@@ -83,9 +83,9 @@ namespace Perspex.Controls
         }
 
         /// <inheritdoc/>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
             _treeView = this.GetVisualAncestors().OfType<TreeView>().FirstOrDefault();
         }
 

src/Perspex.Input/InputElement.cs

@@ -348,9 +348,9 @@ namespace Perspex.Input
         }
 
         /// <inheritdoc/>
-        protected override void OnDetachedFromVisualTree(IRenderRoot oldRoot)
+        protected override void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnDetachedFromVisualTree(oldRoot);
+            base.OnDetachedFromVisualTree(e);
 
             if (IsFocused)
             {
@@ -359,9 +359,9 @@ namespace Perspex.Input
         }
 
         /// <inheritdoc/>
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
+        protected override void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
-            base.OnAttachedToVisualTree(root);
+            base.OnAttachedToVisualTree(e);
             UpdateIsEnabledCore();
         }
 

src/Perspex.SceneGraph/INameScope.cs

@@ -0,0 +1,31 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+namespace Perspex
+{
+    /// <summary>
+    /// Defines a name scope.
+    /// </summary>
+    public interface INameScope
+    {
+        /// <summary>
+        /// Registers an element eith the name scope.
+        /// </summary>
+        /// <param name="name">The element name.</param>
+        /// <param name="element">The element.</param>
+        void Register(string name, object element);
+
+        /// <summary>
+        /// Finds a named element in the name scope.
+        /// </summary>
+        /// <param name="name">The name.</param>
+        /// <returns>The element, or null if the name was not found.</returns>
+        object Find(string name);
+
+        /// <summary>
+        /// Unregisters an element with the name scope.
+        /// </summary>
+        /// <param name="name">The name.</param>
+        void Unregister(string name);
+    }
+}

src/Perspex.Styling/Styling/INamed.cs → src/Perspex.SceneGraph/INamed.cs

@@ -1,10 +1,16 @@
 // Copyright (c) The Perspex Project. All rights reserved.
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
-namespace Perspex.Styling
+namespace Perspex
 {
+    /// <summary>
+    /// Interface for named elements.
+    /// </summary>
     public interface INamed
     {
+        /// <summary>
+        /// Gets the element name.
+        /// </summary>
         string Name { get; }
     }
 }

src/Perspex.SceneGraph/NameScope.cs

@@ -0,0 +1,80 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using System.Collections.Generic;
+
+namespace Perspex
+{
+    /// <summary>
+    /// Implements a name scope.
+    /// </summary>
+    public class NameScope : INameScope
+    {
+        /// <summary>
+        /// Defines the NameScope attached property.
+        /// </summary>
+        public static readonly PerspexProperty<INameScope> NameScopeProperty =
+            PerspexProperty.RegisterAttached<NameScope, Visual, INameScope>("NameScope");
+
+        private Dictionary<string, object> _inner = new Dictionary<string, object>();
+
+        /// <summary>
+        /// Gets the value of the attached <see cref="NameScopeProperty"/> on a visual.
+        /// </summary>
+        /// <param name="visual">The visual.</param>
+        /// <returns>The value of the NameScope attached property.</returns>
+        public static INameScope GetNameScope(Visual visual)
+        {
+            return visual.GetValue(NameScopeProperty);
+        }
+
+        /// <summary>
+        /// Sets the value of the attached <see cref="NameScopeProperty"/> on a visual.
+        /// </summary>
+        /// <param name="visual">The visual.</param>
+        /// <param name="value">The value to set.</param>
+        public static void SetNameScope(Visual visual, INameScope value)
+        {
+            visual.SetValue(NameScopeProperty, value);
+        }
+
+        /// <summary>
+        /// Registers an element with the name scope.
+        /// </summary>
+        /// <param name="name">The element name.</param>
+        /// <param name="element">The element.</param>
+        public void Register(string name, object element)
+        {
+            Contract.Requires<ArgumentNullException>(name != null);
+            Contract.Requires<ArgumentNullException>(element != null);
+
+            _inner.Add(name, element);
+        }
+
+        /// <summary>
+        /// Finds a named element in the name scope.
+        /// </summary>
+        /// <param name="name">The name.</param>
+        /// <returns>The element, or null if the name was not found.</returns>
+        public object Find(string name)
+        {
+            Contract.Requires<ArgumentNullException>(name != null);
+
+            object result;
+            _inner.TryGetValue(name, out result);
+            return result;
+        }
+
+        /// <summary>
+        /// Unregisters an element with the name scope.
+        /// </summary>
+        /// <param name="name">The name.</param>
+        public void Unregister(string name)
+        {
+            Contract.Requires<ArgumentNullException>(name != null);
+
+            _inner.Remove(name);
+        }
+    }
+}

src/Perspex.SceneGraph/NameScopeExtensions.cs

@@ -0,0 +1,68 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using System.Collections.Generic;
+
+namespace Perspex
+{
+    /// <summary>
+    /// Extension methods for <see cref="INameScope"/>.
+    /// </summary>
+    public static class NameScopeExtensions
+    {
+        /// <summary>
+        /// Finds a named element in an <see cref="INameScope"/>.
+        /// </summary>
+        /// <typeparam name="T">The element type.</typeparam>
+        /// <param name="nameScope">The name scope.</param>
+        /// <param name="name">The name.</param>
+        /// <returns>The named element or null if not found.</returns>
+        public static T Find<T>(this INameScope nameScope, string name)
+            where T : class
+        {
+            Contract.Requires<ArgumentNullException>(nameScope != null);
+            Contract.Requires<ArgumentNullException>(name != null);
+
+            var result = nameScope.Find(name);
+
+            if (result != null && !(result is T))
+            {
+                throw new InvalidOperationException(
+                    $"Expected control '{name}' to be '{typeof(T)} but it was '{result.GetType()}'.");
+            }
+
+            return (T)result;
+        }
+
+        /// <summary>
+        /// Gets a named element from an <see cref="INameScope"/> or throws if no element of the
+        /// requested name was found.
+        /// </summary>
+        /// <typeparam name="T">The element type.</typeparam>
+        /// <param name="nameScope">The name scope.</param>
+        /// <param name="name">The name.</param>
+        /// <returns>The named element.</returns>
+        public static T Get<T>(this INameScope nameScope, string name)
+            where T : class
+        {
+            Contract.Requires<ArgumentNullException>(nameScope != null);
+            Contract.Requires<ArgumentNullException>(name != null);
+
+            var result = nameScope.Find(name);
+
+            if (result == null)
+            {
+                throw new KeyNotFoundException($"Could not find control '{name}'.");
+            }
+
+            if (!(result is T))
+            {
+                throw new InvalidOperationException(
+                    $"Expected control '{name}' to be '{typeof(T)} but it was '{result.GetType()}'.");
+            }
+
+            return (T)result;
+        }
+    }
+}

src/Perspex.SceneGraph/Perspex.SceneGraph.csproj

@@ -55,6 +55,8 @@
     <Compile Include="Animation\PageSlide.cs" />
     <Compile Include="Animation\CrossFade.cs" />
     <Compile Include="Animation\IPageTransition.cs" />
+    <Compile Include="INamed.cs" />
+    <Compile Include="INameScope.cs" />
     <Compile Include="Matrix.cs" />
     <Compile Include="Media\AlignmentY.cs" />
     <Compile Include="Media\AlignmentX.cs" />
@@ -101,6 +103,8 @@
     <Compile Include="Media\TileBrush.cs" />
     <Compile Include="Media\ImageBush.cs" />
     <Compile Include="Media\VisualBrush.cs" />
+    <Compile Include="NameScopeExtensions.cs" />
+    <Compile Include="NameScope.cs" />
     <Compile Include="RelativePoint.cs" />
     <Compile Include="Platform\IFormattedTextImpl.cs" />
     <Compile Include="Platform\IBitmapImpl.cs" />
@@ -122,6 +126,7 @@
     <Compile Include="Thickness.cs" />
     <Compile Include="Vector.cs" />
     <Compile Include="Visual.cs" />
+    <Compile Include="VisualTreeAttachmentEventArgs.cs" />
     <Compile Include="VisualTree\IHostedVisualTreeRoot.cs" />
     <Compile Include="VisualTree\IVisualTreeHost.cs" />
     <Compile Include="VisualTree\TransformedBounds.cs" />

src/Perspex.SceneGraph/Visual.cs

@@ -26,7 +26,7 @@ namespace Perspex
     /// To traverse the scene graph (aka Visual Tree), use the extension methods defined
     /// in <see cref="VisualExtensions"/>.
     /// </remarks>
-    public class Visual : Animatable, IVisual
+    public class Visual : Animatable, IVisual, INamed
     {
         /// <summary>
         /// Defines the <see cref="Bounds"/> property.
@@ -76,6 +76,11 @@ namespace Perspex
         public static readonly PerspexProperty<int> ZIndexProperty =
             PerspexProperty.Register<Visual, int>(nameof(ZIndex));
 
+        /// <summary>
+        /// The name of the visual, if any.
+        /// </summary>
+        private string _name;
+
         /// <summary>
         /// Holds the children of the visual.
         /// </summary>
@@ -128,6 +133,16 @@ namespace Perspex
             _visualChildren.CollectionChanged += VisualChildrenChanged;
         }
 
+        /// <summary>
+        /// Raised when the control is attached to a rooted visual tree.
+        /// </summary>
+        public event EventHandler<VisualTreeAttachmentEventArgs> AttachedToVisualTree;
+
+        /// <summary>
+        /// Raised when the control is detached from a rooted visual tree.
+        /// </summary>
+        public event EventHandler<VisualTreeAttachmentEventArgs> DetachedFromVisualTree;
+
         /// <summary>
         /// Gets the bounds of the scene graph node relative to its parent.
         /// </summary>
@@ -163,6 +178,36 @@ namespace Perspex
             set { SetValue(IsVisibleProperty, value); }
         }
 
+        /// <summary>
+        /// Gets or sets the name of the visual.
+        /// </summary>
+        /// <remarks>
+        /// An element's name is used to uniquely identify a control within the control's name
+        /// scope. Once the element is added to a visual tree, its name cannot be changed.
+        /// </remarks>
+        public string Name
+        {
+            get
+            {
+                return _name;
+            }
+
+            set
+            {
+                if (value.Trim() == string.Empty)
+                {
+                    throw new InvalidOperationException("Cannot set Name to empty string.");
+                }
+
+                if (_isAttachedToVisualTree)
+                {
+                    throw new InvalidOperationException("Cannot set Name : control already added to tree.");
+                }
+
+                _name = value;
+            }
+        }
+
         /// <summary>
         /// Gets the opacity of the scene graph node.
         /// </summary>
@@ -340,17 +385,19 @@ namespace Perspex
         /// <summary>
         /// Called when the control is added to a visual tree.
         /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        protected virtual void OnAttachedToVisualTree(IRenderRoot root)
+        /// <param name="e">The event args.</param>
+        protected virtual void OnAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
+            AttachedToVisualTree?.Invoke(this, e);
         }
 
         /// <summary>
         /// Called when the control is removed from a visual tree.
         /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        protected virtual void OnDetachedFromVisualTree(IRenderRoot root)
+        /// <param name="e">The event args.</param>
+        protected virtual void OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
+            DetachedFromVisualTree?.Invoke(this, e);
         }
 
         /// <summary>
@@ -367,6 +414,60 @@ namespace Perspex
             }
         }
 
+        /// <summary>
+        /// Gets the event args for an <see cref="AttachedToVisualTree"/> or
+        /// <see cref="DetachedFromVisualTree"/> event.
+        /// </summary>
+        /// <returns>
+        /// A <see cref="VisualTreeAttachmentEventArgs"/> if the visual currently has a root;
+        /// otherwise null.
+        /// </returns>
+        private VisualTreeAttachmentEventArgs GetAttachmentEventArgs()
+        {
+            var e = (IVisual)this;
+            IRenderRoot root = null;
+            INameScope nameScope = null;
+
+            while (e != null)
+            {
+                if (nameScope == null)
+                {
+                    nameScope = e as INameScope ?? NameScope.GetNameScope((Visual)e);
+                }
+
+                root = e as IRenderRoot;
+
+                if (root != null)
+                {
+                    return new VisualTreeAttachmentEventArgs(root, nameScope);
+                }
+
+                e = e.VisualParent;
+            }
+
+            return null;
+        }
+
+        /// <summary>
+        /// Gets the <see cref="VisualTreeAttachmentEventArgs"/> for this element based on the 
+        /// parent's args.
+        /// </summary>
+        /// <param name="e">The parent args.</param>
+        /// <returns>The args for this element.</returns>
+        private VisualTreeAttachmentEventArgs GetAttachmentEventArgs(VisualTreeAttachmentEventArgs e)
+        {
+            var childNameScope = (this as INameScope) ?? NameScope.GetNameScope(this);
+
+            if (childNameScope != null)
+            {
+                return new VisualTreeAttachmentEventArgs(e.Root, childNameScope);
+            }
+            else
+            {
+                return e;
+            }
+        }
+
         /// <summary>
         /// Gets the root of the controls visual tree and the distance from the root.
         /// </summary>
@@ -436,28 +537,23 @@ namespace Perspex
         {
             if (_visualParent != value)
             {
-                var old = _visualParent;
-                var oldRoot = this.GetVisualAncestors().OfType<IRenderRoot>().FirstOrDefault();
-                var newRoot = default(IRenderRoot);
-
-                if (value != null)
-                {
-                    newRoot = value.GetSelfAndVisualAncestors().OfType<IRenderRoot>().FirstOrDefault();
-                }
+                var oldArgs = GetAttachmentEventArgs();
 
                 _visualParent = value;
 
-                if (oldRoot != null)
+                if (oldArgs != null)
                 {
-                    NotifyDetachedFromVisualTree(oldRoot);
+                    NotifyDetachedFromVisualTree(oldArgs);
                 }
 
-                if (newRoot != null)
+                var newArgs = GetAttachmentEventArgs();
+
+                if (newArgs != null)
                 {
-                    NotifyAttachedToVisualTree(newRoot);
+                    NotifyAttachedToVisualTree(newArgs);
                 }
 
-                RaisePropertyChanged(VisualParentProperty, old, value, BindingPriority.LocalValue);
+                RaisePropertyChanged(VisualParentProperty, oldArgs, value, BindingPriority.LocalValue);
             }
         }
 
@@ -491,43 +587,56 @@ namespace Perspex
         }
 
         /// <summary>
-        /// Calls the <see cref="OnAttachedToVisualTree(IRenderRoot)"/> method for this control
-        /// and all of its visual descendents.
+        /// Calls the <see cref="OnAttachedToVisualTree(VisualTreeAttachmentEventArgs)"/> method 
+        /// for this control and all of its visual descendents.
         /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        private void NotifyAttachedToVisualTree(IRenderRoot root)
+        /// <param name="e">The event args.</param>
+        private void NotifyAttachedToVisualTree(VisualTreeAttachmentEventArgs e)
         {
             _visualLogger.Verbose("Attached to visual tree");
 
             _isAttachedToVisualTree = true;
-            OnAttachedToVisualTree(root);
+
+            if (Name != null && e.NameScope != null)
+            {
+                e.NameScope.Register(Name, this);
+            }
+
+            OnAttachedToVisualTree(e);
 
             if (_visualChildren != null)
             {
                 foreach (Visual child in _visualChildren.OfType<Visual>())
                 {
-                    child.NotifyAttachedToVisualTree(root);
+                    var ce = child.GetAttachmentEventArgs(e);
+                    child.NotifyAttachedToVisualTree(ce);
                 }
             }
         }
 
         /// <summary>
-        /// Calls the <see cref="OnDetachedFromVisualTree(IRenderRoot)"/> method for this control
-        /// and all of its visual descendents.
+        /// Calls the <see cref="OnDetachedFromVisualTree(VisualTreeAttachmentEventArgs)"/> method 
+        /// for this control and all of its visual descendents.
         /// </summary>
-        /// <param name="root">The root of the visual tree.</param>
-        private void NotifyDetachedFromVisualTree(IRenderRoot root)
+        /// <param name="e">The event args.</param>
+        private void NotifyDetachedFromVisualTree(VisualTreeAttachmentEventArgs e)
         {
             _visualLogger.Verbose("Detached from visual tree");
 
+            if (Name != null && e.NameScope != null)
+            {
+                e.NameScope.Unregister(Name);
+            }
+
             _isAttachedToVisualTree = false;
-            OnDetachedFromVisualTree(root);
+            OnDetachedFromVisualTree(e);
 
             if (_visualChildren != null)
             {
                 foreach (Visual child in _visualChildren.OfType<Visual>())
                 {
-                    child.NotifyDetachedFromVisualTree(root);
+                    var ce = child.GetAttachmentEventArgs(e);
+                    child.NotifyDetachedFromVisualTree(ce);
                 }
             }
         }

src/Perspex.SceneGraph/VisualTreeAttachmentEventArgs.cs

@@ -0,0 +1,36 @@
+// Copyright (c) The Perspex Project. All rights reserved.
+// Licensed under the MIT license. See licence.md file in the project root for full license information.
+
+using System;
+using Perspex.Rendering;
+
+namespace Perspex
+{
+    /// <summary>
+    /// Holds the event arguments for the <see cref="Visual.AttachedToVisualTree"/> and 
+    /// <see cref="Visual.DetachedFromVisualTree"/> events.
+    /// </summary>
+    public class VisualTreeAttachmentEventArgs : EventArgs
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="VisualTreeAttachmentEventArgs"/> class.
+        /// </summary>
+        /// <param name="root">The root visual.</param>
+        /// <param name="nameScope">The name scope.</param>
+        public VisualTreeAttachmentEventArgs(IRenderRoot root, INameScope nameScope)
+        {
+            Root = root;
+            NameScope = nameScope;
+        }
+
+        /// <summary>
+        /// Gets the root of the visual tree that the visual is being attached to or detached from.
+        /// </summary>
+        public IRenderRoot Root { get; }
+
+        /// <summary>
+        /// Gets the element's name scope.
+        /// </summary>
+        public INameScope NameScope { get; }
+    }
+}

src/Perspex.Styling/Perspex.Styling.csproj

@@ -46,7 +46,6 @@
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="Styling\Classes.cs" />
     <Compile Include="Styling\IGlobalStyles.cs" />
-    <Compile Include="Styling\INamed.cs" />
     <Compile Include="Styling\ISetter.cs" />
     <Compile Include="Styling\IStyle.cs" />
     <Compile Include="Styling\IStyleable.cs" />

tests/Perspex.Controls.UnitTests/Primitives/PopupTests.cs

@@ -214,7 +214,7 @@ namespace Perspex.Controls.UnitTests.Primitives
                 };
 
                 target.ApplyTemplate();
-                var popup = target.GetTemplateChild<Popup>("popup");
+                var popup = (Popup)target.GetTemplateChildren().First(x => x.Name == "popup");
                 popup.Open();
                 var popupRoot = popup.PopupRoot;
 

tests/Perspex.Controls.UnitTests/Primitives/ScrollBarTests.cs

@@ -2,6 +2,7 @@
 // Licensed under the MIT license. See licence.md file in the project root for full license information.
 
 using System;
+using System.Linq;
 using Perspex.Controls.Primitives;
 using Perspex.Controls.Templates;
 using Perspex.Media;
@@ -20,7 +21,7 @@ namespace Perspex.Controls.UnitTests.Primitives
             };
 
             target.ApplyTemplate();
-            var track = target.GetTemplateChild<Track>("track");
+            var track = (Track)target.GetTemplateChildren().First(x => x.Name == "track");
             target.Value = 50;
 
             Assert.Equal(track.Value, 50);
@@ -35,7 +36,7 @@ namespace Perspex.Controls.UnitTests.Primitives
             };
 
             target.ApplyTemplate();
-            var track = target.GetTemplateChild<Track>("track");
+            var track = (Track)target.GetTemplateChildren().First(x => x.Name == "track");
             track.Value = 50;
 
             Assert.Equal(target.Value, 50);
@@ -51,7 +52,7 @@ namespace Perspex.Controls.UnitTests.Primitives
 
             target.ApplyTemplate();
 
-            var track = target.GetTemplateChild<Track>("track");
+            var track = (Track)target.GetTemplateChildren().First(x => x.Name == "track");
             target.Value = 25;
             track.Value = 50;
 

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

@@ -50,6 +50,29 @@ namespace Perspex.Controls.UnitTests.Primitives
             Assert.Empty(target.GetLogicalChildren());
         }
 
+        [Fact]
+        public void Templated_Child_Should_Be_NameScope()
+        {
+            var target = new TemplatedControl
+            {
+                Template = new FuncControlTemplate(_ => new Decorator
+                {
+                    Child = new Panel
+                    {
+                        Children = new Controls
+                        {
+                            new TextBlock(),
+                            new Border(),
+                        }
+                    }
+                }),
+            };
+
+            target.ApplyTemplate();
+
+            Assert.NotNull(NameScope.GetNameScope((Visual)target.GetVisualChildren().Single()));
+        }
+
         [Fact]
         public void Templated_Children_Should_Have_TemplatedParent_Set()
         {

tests/Perspex.Controls.UnitTests/ScrollViewerTests.cs

@@ -24,9 +24,7 @@ namespace Perspex.Controls.UnitTests
 
             target.ApplyTemplate();
 
-            var presenter = target.GetTemplateChild<ScrollContentPresenter>("contentPresenter");
-
-            Assert.IsType<TextBlock>(presenter.Child);
+            Assert.IsType<TextBlock>(target.Presenter.Child);
         }
 
         [Fact]

tests/Perspex.Controls.UnitTests/TestTemplatedControl.cs

@@ -14,7 +14,7 @@ namespace Perspex.Controls.UnitTests
             base.AddVisualChild(visual);
         }
 
-        protected override void OnTemplateApplied()
+        protected override void OnTemplateApplied(INameScope nameScope)
         {
             OnTemplateAppliedCalled = true;
         }

tests/Perspex.SceneGraph.UnitTests/TestRoot.cs

@@ -7,8 +7,10 @@ using Perspex.Rendering;
 
 namespace Perspex.SceneGraph.UnitTests
 {
-    public class TestRoot : TestVisual, IRenderRoot
+    public class TestRoot : TestVisual, IRenderRoot, INameScope
     {
+        private NameScope nameScope = new NameScope();
+
         public IRenderTarget RenderTarget
         {
             get { throw new NotImplementedException(); }
@@ -23,5 +25,20 @@ namespace Perspex.SceneGraph.UnitTests
         {
             throw new NotImplementedException();
         }
+
+        public void Register(string name, object element)
+        {
+            nameScope.Register(name, element);
+        }
+
+        public object Find(string name)
+        {
+            return nameScope.Find(name);
+        }
+
+        public void Unregister(string name)
+        {
+            nameScope.Unregister(name);
+        }
     }
 }

tests/Perspex.SceneGraph.UnitTests/TestVisual.cs

@@ -20,11 +20,28 @@ namespace Perspex.SceneGraph.UnitTests
 
     public class TestVisual : Visual
     {
-        public event EventHandler<ParamEventArgs<IRenderRoot>> AttachedToVisualTreeCalled;
+        public new PerspexObject InheritanceParent => base.InheritanceParent;
 
-        public event EventHandler<ParamEventArgs<IRenderRoot>> DetachedFromVisualTreeCalled;
+        public IVisual Child
+        {
+            get
+            {
+                return ((IVisual)this).VisualChildren.FirstOrDefault();
+            }
 
-        public new PerspexObject InheritanceParent => base.InheritanceParent;
+            set
+            {
+                if (Child != null)
+                {
+                    RemoveVisualChild(Child);
+                }
+
+                if (value != null)
+                {
+                    AddVisualChild(value);
+                }
+            }
+        }
 
         public void AddChild(Visual v)
         {
@@ -45,21 +62,5 @@ namespace Perspex.SceneGraph.UnitTests
         {
             ClearVisualChildren();
         }
-
-        protected override void OnAttachedToVisualTree(IRenderRoot root)
-        {
-            if (AttachedToVisualTreeCalled != null)
-            {
-                AttachedToVisualTreeCalled(this, new ParamEventArgs<IRenderRoot>(root));
-            }
-        }
-
-        protected override void OnDetachedFromVisualTree(IRenderRoot oldRoot)
-        {
-            if (DetachedFromVisualTreeCalled != null)
-            {
-                DetachedFromVisualTreeCalled(this, new ParamEventArgs<IRenderRoot>(oldRoot));
-            }
-        }
     }
 }

tests/Perspex.SceneGraph.UnitTests/VisualTests.cs

@@ -4,6 +4,7 @@
 using System;
 using System.Collections.Generic;
 using System.Linq;
+using Perspex.Controls;
 using Perspex.VisualTree;
 using Xunit;
 
@@ -84,5 +85,91 @@ namespace Perspex.SceneGraph.UnitTests
 
             Assert.Equal(new Visual[] { null, null }, result);
         }
+
+        [Fact]
+        public void Adding_Children_Should_Fire_OnAttachedToVisualTree()
+        {
+            var child2 = new TestVisual();
+            var child1 = new TestVisual { Child = child2 };
+            var root = new TestRoot();
+            var called1 = false;
+            var called2 = false;
+
+            child1.AttachedToVisualTree += (s, e) => called1 = true;
+            child2.AttachedToVisualTree += (s, e) => called2 = true;
+
+            root.Child = child1;
+
+            Assert.True(called1);
+            Assert.True(called2);
+        }
+
+        [Fact]
+        public void Removing_Children_Should_Fire_OnDetachedFromVisualTree()
+        {
+            var child2 = new TestVisual();
+            var child1 = new TestVisual { Child = child2 };
+            var root = new TestRoot();
+            var called1 = false;
+            var called2 = false;
+
+            root.Child = child1;
+            child1.DetachedFromVisualTree += (s, e) => called1 = true;
+            child2.DetachedFromVisualTree += (s, e) => called2 = true;
+            root.Child = null;
+
+            Assert.True(called1);
+            Assert.True(called2);
+        }
+
+        [Fact]
+        public void Controls_Should_Add_Themselves_To_Root_NameScope()
+        {
+            var child2 = new TestVisual { Name = "bar" };
+            var child1 = new TestVisual { Name = "foo", Child = child2 };
+            var root = new TestRoot { Child = child1 };
+
+            Assert.Same(child1, root.Find("foo"));
+            Assert.Same(child2, root.Find("bar"));
+        }
+
+        [Fact]
+        public void Controls_Should_Add_Themselves_To_NameScopes_In_Attached_Property()
+        {
+            var child2 = new TestVisual { Name = "bar", [NameScope.NameScopeProperty] = new NameScope() };
+            var child1 = new TestVisual { Name = "foo", Child = child2};
+            var root = new TestRoot { Child = child1 };
+
+            Assert.Same(child1, root.Find("foo"));
+            Assert.Null(root.Find("bar"));
+            Assert.Same(child2, NameScope.GetNameScope(child2).Find("bar"));
+        }
+
+        [Fact]
+        public void Controls_Should_Remove_Themselves_From_Root_NameScope()
+        {
+            var child2 = new TestVisual { Name = "bar" };
+            var child1 = new TestVisual { Name = "foo", Child = child2 };
+            var root = new TestRoot { Child = child1 };
+
+            root.Child = null;
+
+            Assert.Null(root.Find("foo"));
+            Assert.Null(root.Find("bar"));
+        }
+
+        [Fact]
+        public void Controls_Should_Remove_Themselves_From_NameScopes_In_Attached_Property()
+        {
+            var child2 = new TestVisual { Name = "bar" };
+            var child1 = new TestVisual { Name = "foo", Child = child2,[NameScope.NameScopeProperty] = new NameScope() };
+            var root = new TestRoot { Child = child1 };
+
+            root.Child = null;
+
+            Assert.Null(root.Find("foo"));
+            Assert.Null(root.Find("bar"));
+            Assert.Null(NameScope.GetNameScope(child1).Find("bar"));
+        }
     }
 }