Manipulate logical parent thru ISetLogicalParent.

Ported from ideas branch. Also includes beginnings of INameScope
support, though nothing implements this interface yet.

Perspex.Controls/Control.cs

@@ -7,11 +7,13 @@
 namespace Perspex.Controls
 {
     using System;
+    using System.Linq;
     using System.Reactive.Linq;
     using Perspex.Collections;
     using Perspex.Controls.Primitives;
     using Perspex.Input;
     using Perspex.Interactivity;
+    using Perspex.LogicalTree;
     using Perspex.Rendering;
     using Perspex.Styling;
     using Splat;
@@ -29,7 +31,7 @@ namespace Perspex.Controls
     /// - Implements <see cref="IStyleable"/> to allow styling to work on the control.
     /// - Implements <see cref="ILogical"/> to form part of a logical tree.
     /// </remarks>
-    public class Control : InputElement, IControl
+    public class Control : InputElement, IControl, ISetLogicalParent
     {
         /// <summary>
         /// Defines the <see cref="DataContext"/> property.
@@ -231,7 +233,6 @@ namespace Perspex.Controls
         public IControl Parent
         {
             get { return this.GetValue(ParentProperty); }
-            internal set { this.SetValue(ParentProperty, value); }
         }
 
         /// <summary>
@@ -306,6 +307,55 @@ namespace Perspex.Controls
             this.RaiseEvent(ev);
         }
 
+        /// <summary>
+        /// Sets the control's logical parent.
+        /// </summary>
+        /// <param name="parent">The parent.</param>
+        void ISetLogicalParent.SetParent(IControl parent)
+        {
+            var old = this.Parent;
+
+            if (old != null && parent != null)
+            {
+                throw new InvalidOperationException("The Control already has a parent.");
+            }
+
+            this.SetValue(ParentProperty, parent);
+
+            if (parent != null)
+            {
+                var nameScope = parent.GetSelfAndLogicalAncestors()
+                    .OfType<INameScope>()
+                    .FirstOrDefault();
+
+                if (nameScope != null)
+                {
+                    this.RegisterName(nameScope);
+
+                    foreach (var descendent in this.GetLogicalDescendents().OfType<Control>())
+                    {
+                        descendent.RegisterName(nameScope);
+                    }
+                }
+            }
+            else if (old != null)
+            {
+                var nameScope = old.GetSelfAndLogicalAncestors()
+                    .OfType<INameScope>()
+                    .FirstOrDefault();
+
+                if (nameScope != null)
+                {
+                    this.UnregisterName(nameScope);
+
+                    foreach (var descendent in this.GetLogicalDescendents().OfType<Control>())
+                    {
+                        descendent.UnregisterName(nameScope);
+                    }
+                }
+            }
+        }
+
         [Obsolete("Obsolete this: use properties instead")]
         protected static void PseudoClass(PerspexProperty<bool> property, string className)
         {
@@ -393,5 +443,29 @@ namespace Perspex.Controls
             IStyler styler = Locator.Current.GetService<IStyler>();
             styler.ApplyStyles(this);
         }
+
+        /// <summary>
+        /// Registers the control with the specified name scope.
+        /// </summary>
+        /// <param name="nameScope">The name scope.</param>
+        private void RegisterName(INameScope nameScope)
+        {
+            if (!string.IsNullOrWhiteSpace(this.Name))
+            {
+                nameScope.RegisterName(this.Name, this);
+            }
+        }
+
+        /// <summary>
+        /// Unregisters the control with the specified name scope.
+        /// </summary>
+        /// <param name="nameScope">The name scope.</param>
+        private void UnregisterName(INameScope nameScope)
+        {
+            if (!string.IsNullOrWhiteSpace(this.Name))
+            {
+                nameScope.UnregisterName(this.Name);
+            }
+        }
     }
 }

Perspex.Controls/Decorator.cs

@@ -102,14 +102,14 @@ namespace Perspex.Controls
 
             if (oldChild != null)
             {
-                oldChild.Parent = null;
+                ((ISetLogicalParent)oldChild).SetParent(null);
                 this.RemoveVisualChild(oldChild);
             }
 
             if (newChild != null)
             {
                 this.AddVisualChild(newChild);
-                newChild.Parent = this;
+                ((ISetLogicalParent)newChild).SetParent(this);
             }
 
             this.logicalChild.SingleItem = newChild;

Perspex.Controls/DropDown.cs

@@ -76,7 +76,6 @@ namespace Perspex.Controls
         protected override void OnTemplateApplied()
         {
             var container = this.GetTemplateChild<Panel>("container");
-            ((IItemsPanel)container).ChildLogicalParent = this;
             this.logicalChildren.Source = ((ILogical)container).LogicalChildren;
         }
 
@@ -87,12 +86,12 @@ namespace Perspex.Controls
 
             if (control1 != null)
             {
-                control1.Parent = null;
+                ((ISetLogicalParent)control1).SetParent(null);
             }
 
             if (control2 != null)
             {
-                control2.Parent = this;
+                ((ISetLogicalParent)control2).SetParent(this);
             }
         }
     }

Perspex.Controls/INameScope.cs

@@ -0,0 +1,40 @@
+// -----------------------------------------------------------------------
+// <copyright file="INameScope.cs" company="Steven Kirk">
+// Copyright 2015 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Controls
+{
+    /// <summary>
+    /// Defines the interface for object which define a name scope.
+    /// </summary>
+    public interface INameScope
+    {
+        /// <summary>
+        /// Returns an object tha thas the requested name.
+        /// </summary>
+        /// <param name="name">The name of the object.</param>
+        /// <returns>The named object or null if the named object was not found.</returns>
+        object FindName(string name);
+
+        /// <summary>
+        /// Registers an object with the specified name in the name scope.
+        /// </summary>
+        /// <param name="name">The name of the object.</param>
+        /// <param name="o">The object.</param>
+        /// <exception cref="ArgumentException">
+        /// An object with the same name has already been registered.
+        /// </exception>
+        void RegisterName(string name, object o);
+
+        /// <summary>
+        /// Unregisters the specified name in the name scope.
+        /// </summary>
+        /// <param name="name">The name of the object.</param>
+        /// <exception cref="ArgumentException">
+        /// The name does not exist in the name scope.
+        /// </exception>
+        void UnregisterName(string name);
+    }
+}

Perspex.Controls/ISetLogicalParent.cs

@@ -0,0 +1,23 @@
+// -----------------------------------------------------------------------
+// <copyright file="ISetLogicalParent.cs" company="Steven Kirk">
+// Copyright 2015 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Controls
+{
+    /// <summary>
+    /// Defines an interface through which a <see cref="Control"/>'s logical parent can be set.
+    /// </summary>
+    /// <remarks>
+    /// You should not usually need to use this interface - it is for advanced scenarios only.
+    /// </remarks>
+    public interface ISetLogicalParent
+    {
+        /// <summary>
+        /// Sets the control's parent.
+        /// </summary>
+        /// <param name="parent">The parent.</param>
+        void SetParent(IControl parent);
+    }
+}

Perspex.Controls/Panel.cs

@@ -122,7 +122,7 @@ namespace Perspex.Controls
         {
             foreach (var control in controls)
             {
-                control.Parent = null;
+                ((ISetLogicalParent)control).SetParent(null);
             }
         }
 
@@ -132,9 +132,11 @@ namespace Perspex.Controls
         /// <param name="controls">The controls.</param>
         private void SetLogicalParent(IEnumerable<Control> controls)
         {
+            var parent = this.childLogicalParent as Control;
+
             foreach (var control in controls)
             {
-                control.Parent = this.childLogicalParent as Control;
+                ((ISetLogicalParent)control).SetParent(parent);
             }
         }
 

Perspex.Controls/Perspex.Controls.csproj

@@ -37,6 +37,8 @@
   </PropertyGroup>
   <ItemGroup>
     <Compile Include="IControl.cs" />
+    <Compile Include="INameScope.cs" />
+    <Compile Include="ISetLogicalParent.cs" />
     <Compile Include="MenuItemAccessKeyHandler.cs" />
     <Compile Include="Parsers\GridLengthsParser.cs" />
     <Compile Include="Primitives\AccessText.cs" />

Perspex.Controls/Popup.cs

@@ -185,7 +185,6 @@ namespace Perspex.Controls
             {
                 this.popupRoot = new PopupRoot(this.DependencyResolver)
                 {
-                    Parent = this,
                     [~PopupRoot.ContentProperty] = this[~ChildProperty],
                     [~PopupRoot.WidthProperty] = this[~WidthProperty],
                     [~PopupRoot.HeightProperty] = this[~HeightProperty],
@@ -194,6 +193,8 @@ namespace Perspex.Controls
                     [~PopupRoot.MinHeightProperty] = this[~MinHeightProperty],
                     [~PopupRoot.MaxHeightProperty] = this[~MaxHeightProperty],
                 };
+
+                ((ISetLogicalParent)this.popupRoot).SetParent(this);
             }
 
             this.popupRoot.SetPosition(this.GetPosition());
@@ -279,12 +280,12 @@ namespace Perspex.Controls
         {
             if (values.Item1 != null)
             {
-                values.Item1.Parent = null;
+                ((ISetLogicalParent)values.Item1).SetParent(null);
             }
 
             if (values.Item2 != null)
             {
-                values.Item2.Parent = this;
+                ((ISetLogicalParent)values.Item2).SetParent(this);
             }
 
             this.logicalChild.SingleItem = values.Item2;

Perspex.Controls/Presenters/ContentPresenter.cs

@@ -87,7 +87,11 @@ namespace Perspex.Controls.Presenters
             if (content != null)
             {
                 result = this.MaterializeDataTemplate(content);
-                result.Parent = this.TemplatedParent as Control;
+
+                if (result.Parent == null)
+                {
+                    ((ISetLogicalParent)result).SetParent(this.TemplatedParent as Control);
+                }
 
                 var templatedParent = this.TemplatedParent as TemplatedControl;
 

Perspex.Controls/Primitives/AdornerDecorator.cs

@@ -11,7 +11,7 @@ namespace Perspex.Controls.Primitives
         public AdornerDecorator()
         {
             this.AdornerLayer = new AdornerLayer();
-            this.AdornerLayer.Parent = this;
+            ((ISetLogicalParent)this.AdornerLayer).SetParent(this);
             this.AdornerLayer.ZIndex = int.MaxValue;
             this.AddVisualChild(this.AdornerLayer);
         }

Perspex.Controls/Primitives/TemplatedControl.cs

@@ -140,7 +140,7 @@ namespace Perspex.Controls.Primitives
                     var child = this.Template.Build(this);
                     this.SetTemplatedParent(child);
                     this.AddVisualChild(child);
-                    child.Parent = this;
+                    ((ISetLogicalParent)child).SetParent(this);
 
                     foreach (var i in this.GetTemplateChildren())
                     {

Perspex.Controls/ToolTip.cs

@@ -117,7 +117,7 @@ namespace Perspex.Controls
                 var cp = MouseDevice.Instance.GetPosition(control);
                 var position = control.PointToScreen(cp) + new Vector(0, 22);
 
-                popup.Parent = control;
+                ((ISetLogicalParent)popup).SetParent(control);
                 ((ToolTip)popup.Content).Content = GetTip(control);
                 popup.SetPosition(position);
                 popup.Show();