Allow TabControl to reparent children of its Deck.

Perspex.Controls/ContentControl.cs

@@ -1,6 +1,6 @@
 // -----------------------------------------------------------------------
 // <copyright file="ContentControl.cs" company="Steven Kirk">
-// Copyright 2014 MIT Licence. See licence.md for more information.
+// Copyright 2015 MIT Licence. See licence.md for more information.
 // </copyright>
 // -----------------------------------------------------------------------
 
@@ -13,52 +13,97 @@ namespace Perspex.Controls
     using Perspex.Controls.Templates;
     using Perspex.Layout;
 
-    public class ContentControl : TemplatedControl, IContentControl
+    /// <summary>
+    /// Displays <see cref="Content"/> according to a <see cref="DataTemplate"/>.
+    /// </summary>
+    public class ContentControl : TemplatedControl, IContentControl, IReparentingHost
     {
+        /// <summary>
+        /// Defines the <see cref="Content"/> property.
+        /// </summary>
         public static readonly PerspexProperty<object> ContentProperty =
-            PerspexProperty.Register<ContentControl, object>("Content");
+            PerspexProperty.Register<ContentControl, object>(nameof(Content));
 
+        /// <summary>
+        /// Defines the <see cref="HorizontalContentAlignment"/> property.
+        /// </summary>
         public static readonly PerspexProperty<HorizontalAlignment> HorizontalContentAlignmentProperty =
-            PerspexProperty.Register<ContentControl, HorizontalAlignment>("HorizontalContentAlignment");
+            PerspexProperty.Register<ContentControl, HorizontalAlignment>(nameof(HorizontalContentAlignment));
 
+        /// <summary>
+        /// Defines the <see cref="VerticalContentAlignment"/> property.
+        /// </summary>
         public static readonly PerspexProperty<VerticalAlignment> VerticalContentAlignmentProperty =
-            PerspexProperty.Register<ContentControl, VerticalAlignment>("VerticalContentAlignment");
+            PerspexProperty.Register<ContentControl, VerticalAlignment>(nameof(VerticalContentAlignment));
 
+        /// <summary>
+        /// Initializes a new instance of the <see cref="ContentControl"/> class.
+        /// </summary>
         public ContentControl()
         {
         }
 
+        /// <summary>
+        /// Gets or sets the content to display.
+        /// </summary>
         public object Content
         {
             get { return this.GetValue(ContentProperty); }
             set { this.SetValue(ContentProperty, value); }
         }
 
+        /// <summary>
+        /// Gets the presenter from the control's template.
+        /// </summary>
         public ContentPresenter Presenter
         {
             get;
             private set;
         }
 
+        /// <summary>
+        /// Gets or sets the horizontal alignment of the content within the control.
+        /// </summary>
         public HorizontalAlignment HorizontalContentAlignment
         {
             get { return this.GetValue(HorizontalContentAlignmentProperty); }
             set { this.SetValue(HorizontalContentAlignmentProperty, value); }
         }
 
+        /// <summary>
+        /// Gets or sets the vertical alignment of the content within the control.
+        /// </summary>
         public VerticalAlignment VerticalContentAlignment
         {
             get { return this.GetValue(VerticalContentAlignmentProperty); }
             set { this.SetValue(VerticalContentAlignmentProperty, value); }
         }
 
+        /// <summary>
+        /// Gets a writeable logical children collection from the host.
+        /// </summary>
+        IPerspexList<ILogical> IReparentingHost.LogicalChildren => this.LogicalChildren;
+
+        /// <summary>
+        /// Asks the control whether it wants to reparent the logical children of the specified
+        /// control.
+        /// </summary>
+        /// <param name="control">The control.</param>
+        /// <returns>
+        /// True if the control wants to reparent its logical children otherwise false.
+        /// </returns>
+        bool IReparentingHost.WillReparentChildrenOf(IControl control)
+        {
+            return control is IContentPresenter && control.TemplatedParent == this;
+        }
+
+        /// <inheritdoc/>
         protected override void OnTemplateApplied()
         {
             // 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.
             this.Presenter = this.FindTemplateChild<ContentPresenter>("contentPresenter");
-            ((IReparentingControl)this.Presenter)?.ReparentLogicalChildren(this, this.LogicalChildren);
         }
     }
 }

Perspex.Controls/DropDown.cs

@@ -69,7 +69,6 @@ namespace Perspex.Controls
         protected override void OnTemplateApplied()
         {
             var container = this.GetTemplateChild<Panel>("container");
-            ((IReparentingControl)container).ReparentLogicalChildren(this, this.LogicalChildren);
         }
 
         private void SetContentParent(Tuple<object, object> change)

Perspex.Controls/IReparentingHost.cs

@@ -0,0 +1,31 @@
+// -----------------------------------------------------------------------
+// <copyright file="IReparentingHost.cs" company="Steven Kirk">
+// Copyright 2015 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Controls
+{
+    using Perspex.Collections;
+
+    /// <summary>
+    /// A control that can use the visual children of another control as its logical children.
+    /// </summary>
+    public interface IReparentingHost : ILogical
+    {
+        /// <summary>
+        /// Gets a writeable logical children collection from the host.
+        /// </summary>
+        new IPerspexList<ILogical> LogicalChildren { get; }
+
+        /// <summary>
+        /// Asks the control whether it wants to reparent the logical children of the specified
+        /// control.
+        /// </summary>
+        /// <param name="control">The control.</param>
+        /// <returns>
+        /// True if the control wants to reparent its logical children otherwise false.
+        /// </returns>
+        bool WillReparentChildrenOf(IControl control);
+    }
+}

Perspex.Controls/ItemsControl.cs

@@ -22,7 +22,7 @@ namespace Perspex.Controls
     /// <summary>
     /// Displays a collection of items.
     /// </summary>
-    public class ItemsControl : TemplatedControl
+    public class ItemsControl : TemplatedControl, IReparentingHost
     {
         /// <summary>
         /// The default value for the <see cref="ItemsPanel"/> property.
@@ -45,8 +45,6 @@ namespace Perspex.Controls
 
         private IItemContainerGenerator itemContainerGenerator;
 
-        private IItemsPresenter presenter;
-
         /// <summary>
         /// Initializes static members of the <see cref="ItemsControl"/> class.
         /// </summary>
@@ -102,16 +100,27 @@ namespace Perspex.Controls
         /// </summary>
         public IItemsPresenter Presenter
         {
-            get
-            {
-                return this.presenter;
-            }
+            get;
+            set;
+        }
 
-            protected set
-            {
-                this.presenter = value;
-                (value as IReparentingControl)?.ReparentLogicalChildren(this, this.LogicalChildren);
-            }
+        /// <inheritdoc/>
+        IPerspexList<ILogical> IReparentingHost.LogicalChildren
+        {
+            get { return this.LogicalChildren; }
+        }
+
+        /// <summary>
+        /// Asks the control whether it wants to reparent the logical children of the specified
+        /// control.
+        /// </summary>
+        /// <param name="control">The control.</param>
+        /// <returns>
+        /// True if the control wants to reparent its logical children otherwise false.
+        /// </returns>
+        bool IReparentingHost.WillReparentChildrenOf(IControl control)
+        {
+            return control is IItemsPresenter && control.TemplatedParent == this;
         }
 
         /// <summary>

Perspex.Controls/Perspex.Controls.csproj

@@ -39,10 +39,12 @@
     <Compile Include="Generators\ITreeItemContainerGenerator.cs" />
     <Compile Include="Generators\ItemContainers.cs" />
     <Compile Include="IControl.cs" />
+    <Compile Include="IReparentingHost.cs" />
     <Compile Include="ISetLogicalParent.cs" />
     <Compile Include="MenuItemAccessKeyHandler.cs" />
     <Compile Include="Mixins\SelectableMixin.cs" />
     <Compile Include="Parsers\GridLengthsParser.cs" />
+    <Compile Include="Presenters\IContentPresenter.cs" />
     <Compile Include="Primitives\AccessText.cs" />
     <Compile Include="Border.cs" />
     <Compile Include="GlobalSuppressions.cs" />

Perspex.Controls/Presenters/ContentPresenter.cs

@@ -6,16 +6,12 @@
 
 namespace Perspex.Controls.Presenters
 {
-    using System.Linq;
-    using System.Reactive.Linq;
-    using Perspex.Collections;
-    using Perspex.Controls.Primitives;
     using Perspex.Controls.Templates;
 
     /// <summary>
     /// Presents a single item of data inside a <see cref="TemplatedControl"/> template.
     /// </summary>
-    public class ContentPresenter : Control, IPresenter
+    public class ContentPresenter : Control, IContentPresenter
     {
         /// <summary>
         /// Defines the <see cref="Content"/> property.
@@ -25,8 +21,6 @@ namespace Perspex.Controls.Presenters
 
         private bool createdChild;
 
-        private ILogical logicalParent;
-
         /// <summary>
         /// Initializes static members of the <see cref="ContentPresenter"/> class.
         /// </summary>
@@ -40,7 +34,8 @@ namespace Perspex.Controls.Presenters
         /// </summary>
         public IControl Child
         {
-            get { return (Control)this.LogicalChildren.SingleOrDefault(); }
+            get;
+            private set;
         }
 
         /// <summary>
@@ -61,20 +56,6 @@ namespace Perspex.Controls.Presenters
             }
         }
 
-        /// <inheritdoc/>
-        void IReparentingControl.ReparentLogicalChildren(ILogical logicalParent, IPerspexList<ILogical> children)
-        {
-            if (this.Child != null)
-            {
-                ((ISetLogicalParent)this.Child).SetParent(null);
-                ((ISetLogicalParent)this.Child).SetParent(logicalParent);
-                children.Add(this.Child);
-            }
-
-            this.logicalParent = logicalParent;
-            this.RedirectLogicalChildren(children);
-        }
-
         /// <inheritdoc/>
         protected override Size MeasureCore(Size availableSize)
         {
@@ -110,23 +91,29 @@ namespace Perspex.Controls.Presenters
         /// </summary>
         private void CreateChild()
         {
-            IControl result = null;
-            object content = this.Content;
+            var old = this.Child;
+            var content = this.Content;
+            var result = content != null ? this.MaterializeDataTemplate(content) : null;
+            var logicalHost = this.FindReparentingHost();
+            var logicalChildren = logicalHost?.LogicalChildren ?? this.LogicalChildren;
 
-            this.LogicalChildren.Clear();
+            logicalChildren.Remove(old);
             this.ClearVisualChildren();
 
-            if (content != null)
+            this.Child = result;
+
+            if (result != null)
             {
-                result = this.MaterializeDataTemplate(content);
+                this.AddVisualChild(result);
 
                 if (result.Parent == null)
                 {
-                    ((ISetLogicalParent)result).SetParent(this.logicalParent ?? this);
+                    ((ISetLogicalParent)result).SetParent((ILogical)logicalHost ?? this);
+
                 }
 
-                this.AddVisualChild(result);
-                this.LogicalChildren.Add(result);
+                logicalChildren.Remove(old);
+                logicalChildren.Add(result);
             }
 
             this.createdChild = true;

Perspex.Controls/Presenters/DeckPresenter.cs

@@ -15,6 +15,7 @@ namespace Perspex.Controls.Presenters
     using Perspex.Collections;
     using Perspex.Controls.Generators;
     using Perspex.Controls.Primitives;
+    using Templates;
     using Perspex.Controls.Utils;
 
     /// <summary>
@@ -140,28 +141,28 @@ namespace Perspex.Controls.Presenters
             }
         }
 
-        /// <inheritdoc/>
-        void IReparentingControl.ReparentLogicalChildren(ILogical logicalParent, IPerspexList<ILogical> children)
-        {
-            this.ApplyTemplate();
-            ((IReparentingControl)this.Panel).ReparentLogicalChildren(logicalParent, children);
-        }
-
         /// <summary>
         /// Creates the <see cref="Panel"/>.
         /// </summary>
         private void CreatePanel()
         {
+            var logicalHost = this.FindReparentingHost();
+
             this.ClearVisualChildren();
+            this.Panel = this.ItemsPanel.Build();
+            this.Panel.SetValue(TemplatedParentProperty, this.TemplatedParent);
+
+            this.AddVisualChild(this.Panel);
 
-            if (this.ItemsPanel != null)
+            if (logicalHost != null)
             {
-                this.Panel = this.ItemsPanel.Build();
-                this.Panel.TemplatedParent = this.TemplatedParent;
-                this.AddVisualChild(this.Panel);
-                this.createdPanel = true;
-                var task = this.MoveToPage(-1, this.SelectedIndex);
+                ((IReparentingControl)this.Panel).ReparentLogicalChildren(
+                    logicalHost,
+                    logicalHost.LogicalChildren);
             }
+
+            this.createdPanel = true;
+            var task = this.MoveToPage(-1, this.SelectedIndex);
         }
 
         /// <summary>

Perspex.Controls/Presenters/IContentPresenter.cs

@@ -0,0 +1,25 @@
+// -----------------------------------------------------------------------
+// <copyright file="IContentPresenter.cs" company="Steven Kirk">
+// Copyright 2015 MIT Licence. See licence.md for more information.
+// </copyright>
+// -----------------------------------------------------------------------
+
+namespace Perspex.Controls.Presenters
+{
+    /// <summary>
+    /// Interface for controls that present a single item of data inside a 
+    /// <see cref="TemplatedControl"/> template.
+    /// </summary>
+    public interface IContentPresenter : IPresenter
+    {
+        /// <summary>
+        /// Gets the control displayed by the presenter.
+        /// </summary>
+        IControl Child { get; }
+
+        /// <summary>
+        /// Gets or sets the content to be displayed by the presenter.
+        /// </summary>
+        object Content { get; set; }
+    }
+}

Perspex.Controls/Presenters/IPresenter.cs

@@ -18,7 +18,7 @@ namespace Perspex.Controls.Presenters
     /// of a <see cref="TemplatedControl"/> then that signals that the visual child
     /// of the presenter is not a part of the template.
     /// </remarks>
-    public interface IPresenter : IControl, INamed, IReparentingControl
+    public interface IPresenter : IControl, INamed
     {
     }
 }

Perspex.Controls/Presenters/ItemsPresenter.cs

@@ -9,15 +9,15 @@ namespace Perspex.Controls.Presenters
     using System;
     using System.Collections;
     using System.Collections.Specialized;
-    using Collections;
     using Perspex.Controls.Generators;
+    using Templates;
     using Perspex.Input;
     using Perspex.Styling;
 
     /// <summary>
     /// Displays items inside an <see cref="ItemsControl"/>.
     /// </summary>
-    public class ItemsPresenter : Control, IItemsPresenter, ITemplatedControl, IReparentingControl
+    public class ItemsPresenter : Control, IItemsPresenter, ITemplatedControl
     {
         /// <summary>
         /// Defines the <see cref="Items"/> property.
@@ -110,13 +110,6 @@ namespace Perspex.Controls.Presenters
             }
         }
 
-        /// <inheritdoc/>
-        public void ReparentLogicalChildren(ILogical logicalParent, IPerspexList<ILogical> children)
-        {
-            this.ApplyTemplate();
-            ((IReparentingControl)this.Panel).ReparentLogicalChildren(logicalParent, children);
-        }
-
         /// <inheritdoc/>
         protected override Size MeasureOverride(Size availableSize)
         {
@@ -140,8 +133,19 @@ namespace Perspex.Controls.Presenters
             this.ClearVisualChildren();
             this.Panel = this.ItemsPanel.Build();
             this.Panel.SetValue(TemplatedParentProperty, this.TemplatedParent);
-            KeyboardNavigation.SetTabNavigation(this.Panel, KeyboardNavigation.GetTabNavigation(this));
+
             this.AddVisualChild(this.Panel);
+
+            var logicalHost = this.FindReparentingHost();
+
+            if (logicalHost != null)
+            {
+                ((IReparentingControl)this.Panel).ReparentLogicalChildren(
+                    logicalHost,
+                    logicalHost.LogicalChildren);
+            }
+
+            KeyboardNavigation.SetTabNavigation(this.Panel, KeyboardNavigation.GetTabNavigation(this));
             this.createdPanel = true;
             this.CreateItemsAndListenForChanges(this.Items);
         }

Perspex.Controls/TabControl.cs

@@ -7,13 +7,13 @@
 namespace Perspex.Controls
 {
     using Perspex.Animation;
+    using Perspex.Controls.Presenters;
     using Perspex.Controls.Primitives;
-    using Perspex.Controls.Templates;
 
     /// <summary>
     /// A tab control that displays a tab strip along with the content of the selected tab.
     /// </summary>
-    public class TabControl : SelectingItemsControl
+    public class TabControl : SelectingItemsControl, IReparentingHost
     {
         /// <summary>
         /// Defines the <see cref="SelectedContent"/> property.
@@ -70,15 +70,17 @@ namespace Perspex.Controls
             set { this.SetValue(TransitionProperty, value); }
         }
 
-        /// <inheritdoc/>
-        protected override void OnTemplateApplied()
+        /// <summary>
+        /// Asks the control whether it wants to reparent the logical children of the specified
+        /// control.
+        /// </summary>
+        /// <param name="control">The control.</param>
+        /// <returns>
+        /// True if the control wants to reparent its logical children otherwise false.
+        /// </returns>
+        bool IReparentingHost.WillReparentChildrenOf(IControl control)
         {
-            base.OnTemplateApplied();
-
-            var deck = this.GetTemplateChild<Deck>("deck");
-            ((IReparentingControl)deck.Presenter.Panel).ReparentLogicalChildren(
-                this,
-                this.LogicalChildren);
+            return control is DeckPresenter;
         }
 
         /// <summary>

Perspex.Controls/Templates/TemplateExtensions.cs

@@ -15,6 +15,35 @@ namespace Perspex.Controls.Templates
 
     public static class TemplateExtensions
     {
+        public static IReparentingHost FindReparentingHost(this IControl control)
+        {
+            var tp = control.TemplatedParent;
+            var chain = new List<IReparentingHost>();
+
+            while (tp != null)
+            {
+                var reparentingHost = tp as IReparentingHost;
+                var styleable = tp as IStyleable;
+
+                if (reparentingHost != null)
+                {
+                    chain.Add(reparentingHost);
+                }
+
+                tp = styleable?.TemplatedParent ?? null;
+            }
+
+            foreach (var reparenting in chain.AsEnumerable().Reverse())
+            {
+                if (reparenting.WillReparentChildrenOf(control))
+                {
+                    return reparenting;
+                }
+            }
+
+            return null;
+        }
+
         public static T FindTemplateChild<T>(this ITemplatedControl control, string id) where T : INamed
         {
             return control.GetTemplateChildren().OfType<T>().SingleOrDefault(x => x.Name == id);

Perspex.Themes.Default/TabStripStyle.cs

@@ -26,7 +26,7 @@ namespace Perspex.Themes.Default
                         new Setter(TabStrip.TemplateProperty, new ControlTemplate<TabStrip>(this.Template)),
                     },
                 },
-                new Style(x => x.OfType<TabStrip>().Template().OfType<ItemsPresenter>().Template().OfType<StackPanel>())
+                new Style(x => x.OfType<TabStrip>().Template().OfType<StackPanel>())
                 {
                     Setters = new[]
                     {

Tests/Perspex.Controls.UnitTests/ContentControlTests.cs

@@ -218,8 +218,7 @@ namespace Perspex.Controls.UnitTests
             target.Content = child;
             target.ApplyTemplate();
 
-            ((ILogical)target).LogicalChildren.CollectionChanged += (s, e) =>
-                called = e.Action == NotifyCollectionChangedAction.Remove;
+            ((ILogical)target).LogicalChildren.CollectionChanged += (s, e) => called = true;
 
             target.Content = null;
 

Tests/Perspex.Controls.UnitTests/TabControlTests.cs

@@ -41,33 +41,6 @@ namespace Perspex.Controls.UnitTests
 
             Assert.Equal(selected, target.SelectedItem);
             Assert.Equal(selected, target.SelectedTab);
-            Assert.Equal("foo", target.SelectedContent);
-        }
-
-        [Fact]
-        public void SelectedContent_Should_Initially_Be_First_Tab_Content()
-        {
-            var target = new TabControl
-            {
-                Template = new ControlTemplate<TabControl>(this.CreateTabControlTemplate),
-                Items = new[]
-                {
-                    new TabItem
-                    {
-                        Name = "first",
-                        Content = "foo",
-                    },
-                    new TabItem
-                    {
-                        Name = "second",
-                        Content = "bar",
-                    },
-                }
-            };
-
-            target.ApplyTemplate();
-
-            Assert.Equal("foo", target.SelectedContent);
         }
 
         [Fact]
@@ -95,7 +68,6 @@ namespace Perspex.Controls.UnitTests
             target.SelectedItem = target.Items.Cast<TabItem>().ElementAt(1);
 
             Assert.Same(target.SelectedTab, target.SelectedItem);
-            Assert.Equal("bar", target.SelectedContent);
         }
 
         [Fact]