Allow editing the "Content" and "Header" properties.

git-svn-id: svn://svn.sharpdevelop.net/sharpdevelop/trunk@2444 1ccf3a8d-04fe-1044-b7c0-cef0b8235c61

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/Controls/GridAdorner.cs

@@ -118,6 +118,8 @@ namespace ICSharpCode.WpfDesign.Designer.Controls
 						rowCollection.CollectionElements.Insert(i + 1, newRowDefinition);
 						rowCollection.CollectionElements[i].Properties[RowDefinition.HeightProperty].SetValue(newLength1);
 						newRowDefinition.Properties[RowDefinition.HeightProperty].SetValue(newLength2);
+						
+						FixIndicesAfterSplit(i, Grid.RowProperty, Grid.RowSpanProperty);
 						changeGroup.Commit();
 						gridItem.Services.Selection.SetSelectedComponents(new DesignItem[] { newRowDefinition }, SelectionTypes.Auto);
 						break;
@@ -141,10 +143,11 @@ namespace ICSharpCode.WpfDesign.Designer.Controls
 						GridLength oldLength = (GridLength)column.GetValue(ColumnDefinition.WidthProperty);
 						GridLength newLength1, newLength2;
 						SplitLength(oldLength, insertionPosition - column.Offset, column.ActualWidth, out newLength1, out newLength2);
-						columnCollection.CollectionElements[i].Properties[ColumnDefinition.WidthProperty].SetValue(newLength1);
 						DesignItem newColumnDefinition = gridItem.Services.Component.RegisterComponentForDesigner(new ColumnDefinition());
-						newColumnDefinition.Properties[ColumnDefinition.WidthProperty].SetValue(newLength2);
 						columnCollection.CollectionElements.Insert(i + 1, newColumnDefinition);
+						columnCollection.CollectionElements[i].Properties[ColumnDefinition.WidthProperty].SetValue(newLength1);
+						newColumnDefinition.Properties[ColumnDefinition.WidthProperty].SetValue(newLength2);
+						FixIndicesAfterSplit(i, Grid.ColumnProperty, Grid.ColumnSpanProperty);
 						changeGroup.Commit();
 						gridItem.Services.Selection.SetSelectedComponents(new DesignItem[] { newColumnDefinition }, SelectionTypes.Auto);
 						break;
@@ -153,6 +156,20 @@ namespace ICSharpCode.WpfDesign.Designer.Controls
 			}
 		}
 		
+		void FixIndicesAfterSplit(int splitIndex, DependencyProperty idxProperty, DependencyProperty spanProperty)
+		{
+			// increment ColSpan of all controls in the split column, increment Column of all controls in later columns:
+			foreach (DesignItem child in gridItem.Properties["Children"].CollectionElements) {
+				int start = (int)child.Properties.GetAttachedProperty(idxProperty).ValueOnInstance;
+				int span = (int)child.Properties.GetAttachedProperty(spanProperty).ValueOnInstance;
+				if (start <= splitIndex && splitIndex < start + span) {
+					child.Properties.GetAttachedProperty(spanProperty).SetValue(span + 1);
+				} else if (start > splitIndex) {
+					child.Properties.GetAttachedProperty(idxProperty).SetValue(start + 1);
+				}
+			}
+		}
+		
 		void SplitLength(GridLength oldLength, double insertionPosition, double oldActualValue,
 		                 out GridLength newLength1, out GridLength newLength2)
 		{

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/Controls/PropertyEditor/PropertyEditor.cs

@@ -35,7 +35,7 @@ namespace ICSharpCode.WpfDesign.Designer
 		// this is not compiled, but gives us code-completion inside SharpDevelop
 		TextBox nameTextBox;
 		Label typeLabel;
-		Image componentImage;
+		Rectangle componentImage;
 		TextBox searchTextBox;
 		StackPanel contentStackPanel;
 		#endif
@@ -73,7 +73,9 @@ namespace ICSharpCode.WpfDesign.Designer
 		
 		void OnEditedObjectPropertyChanged(DependencyPropertyChangedEventArgs e)
 		{
-			ShowProperties(e.NewValue as IPropertyEditorDataSource);
+			IPropertyEditorDataSource dataSource = e.NewValue as IPropertyEditorDataSource;
+			componentImage.Fill = dataSource != null ? dataSource.CreateThumbnailBrush() : null;
+			ShowProperties(dataSource);
 			if (EditedObjectChanged != null) {
 				EditedObjectChanged(this, EventArgs.Empty);
 			}

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/Controls/PropertyEditor/PropertyEditor.xaml

@@ -13,7 +13,7 @@
 						<ColumnDefinition Width="*" />
 						<ColumnDefinition Width="Auto" />
 					</Grid.ColumnDefinitions>
-					<Image Grid.Column="0" Width="32" Height="32" Name="componentImage" />
+					<Rectangle Grid.Column="0" Width="32" Height="32" Name="componentImage"/>
 					<Grid Grid.Column="1" Margin="0 0 2 0">
 						<Grid.ColumnDefinitions>
 							<ColumnDefinition Width="Auto" />

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/Controls/TypeEditors/ContentEditor.cs

@@ -0,0 +1,139 @@
+// <file>
+//     <copyright see="prj:///doc/copyright.txt"/>
+//     <license see="prj:///doc/license.txt"/>
+//     <owner name="Daniel Grunwald" email="daniel@danielgrunwald.de"/>
+//     <version>$Revision$</version>
+// </file>
+
+using System;
+using System.Diagnostics;
+using System.Windows;
+using System.Windows.Data;
+using System.Windows.Controls;
+using System.Windows.Documents;
+using System.Windows.Media;
+using System.Windows.Threading;
+using ICSharpCode.WpfDesign.PropertyEditor;
+
+namespace ICSharpCode.WpfDesign.Designer.Controls.TypeEditors
+{
+	/// <summary>
+	/// Description of ContentEditor.
+	/// </summary>
+	[PropertyEditor(typeof(ContentControl), "Content")]
+	[PropertyEditor(typeof(HeaderedContentControl), "Header")]
+	[PropertyEditor(typeof(HeaderedItemsControl), "Header")]
+	public class ContentEditor : DockPanel
+	{
+		readonly IPropertyEditorDataProperty property;
+		Button createObjectButton = new Button();
+		readonly TextBoxEditor textBoxEditor;
+		readonly FallbackEditor fallbackEditor;
+		readonly DataPropertyWithCustomOnValueChangedEvent textBoxEditorDataProperty, fallbackEditorDataProperty;
+		UIElement activeEditor;
+		DataPropertyWithCustomOnValueChangedEvent activeEditorDataProperty;
+		
+		public ContentEditor(IPropertyEditorDataProperty property)
+		{
+			this.property = property;
+			PropertyEditorBindingHelper.AddValueChangedEventHandler(this, property, OnValueChanged);
+			
+			createObjectButton.Content = "C";
+			createObjectButton.ContextMenuOpening += delegate {
+				createObjectButton.ContextMenu = CreateContextMenu();
+			};
+			createObjectButton.Click += delegate {
+				createObjectButton.ContextMenu = CreateContextMenu();
+				createObjectButton.ContextMenu.IsOpen = true;
+			};
+			SetDock(createObjectButton, Dock.Right);
+			this.Children.Add(createObjectButton);
+			
+			textBoxEditor = new TextBoxEditor(textBoxEditorDataProperty = new DataPropertyWithCustomOnValueChangedEvent(property));
+			fallbackEditor = new FallbackEditor(fallbackEditorDataProperty = new DataPropertyWithCustomOnValueChangedEvent(property));
+			
+			OnValueChanged(null, null);
+		}
+		
+		#region CreateObjectButton Context menu
+		ContextMenu CreateContextMenu()
+		{
+			ContextMenu contextMenu = new ContextMenu();
+			contextMenu.Items.Add(CreateMenuItem("Set to _null", delegate { property.Value = null; }));
+			contextMenu.Items.Add(CreateMenuItem("Create _string", delegate { property.Value = ""; }));
+			return contextMenu;
+		}
+		
+		static MenuItem CreateMenuItem(string title, RoutedEventHandler handler)
+		{
+			MenuItem item = new MenuItem();
+			item.Header = title;
+			item.Click += handler;
+			return item;
+		}
+		#endregion
+		
+		void SetActiveEditor(UIElement newEditor, DataPropertyWithCustomOnValueChangedEvent newDataProperty)
+		{
+			if (activeEditor != newEditor) {
+				if (activeEditorDataProperty != null) {
+					activeEditorDataProperty.preventSetValue = true;
+				}
+				this.Children.Remove(activeEditor);
+				this.Children.Add(newEditor);
+				activeEditor = newEditor;
+				newDataProperty.preventSetValue = false;
+				activeEditorDataProperty = newDataProperty;
+			}
+		}
+		
+		void OnValueChanged(object sender, EventArgs e)
+		{
+			object val = property.Value;
+			if (val is string) {
+				SetActiveEditor(textBoxEditor, textBoxEditorDataProperty);
+			} else {
+				SetActiveEditor(fallbackEditor, fallbackEditorDataProperty);
+			}
+			// raise ValueChanged after the new editor's Loaded event has fired
+			Dispatcher.BeginInvoke(DispatcherPriority.Loaded,
+			                       (Action)activeEditorDataProperty.RaiseValueChanged);
+		}
+		
+		sealed class DataPropertyWithCustomOnValueChangedEvent : ProxyPropertyEditorDataProperty
+		{
+			internal DataPropertyWithCustomOnValueChangedEvent(IPropertyEditorDataProperty property)
+				: base(property)
+			{
+			}
+			
+			EventHandler valueChangedListeners;
+			internal bool preventSetValue;
+			
+			public override object Value {
+				get { return base.Value; }
+				set {
+					if (!preventSetValue) {
+						base.Value = value;
+					}
+				}
+			}
+			
+			public override event EventHandler ValueChanged {
+				add    { valueChangedListeners += value; }
+				remove { valueChangedListeners -= value; }
+			}
+			
+			public override System.ComponentModel.TypeConverter TypeConverter {
+				get { return System.ComponentModel.TypeDescriptor.GetConverter(typeof(string)); }
+			}
+			
+			internal void RaiseValueChanged()
+			{
+				if (valueChangedListeners != null) {
+					valueChangedListeners(this, EventArgs.Empty);
+				}
+			}
+		}
+	}
+}

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/Extensions/GridPlacementSupport.cs

@@ -103,12 +103,15 @@ namespace ICSharpCode.WpfDesign.Designer.Extensions
 				default:
 					throw new NotSupportedException();
 			}
-			return new Rect(left, top, width, height);
+			return new Rect(left, top, Math.Max(0, width), Math.Max(0, height));
 		}
 		
 		double GetColumnOffset(int index)
 		{
-			if (index < grid.ColumnDefinitions.Count)
+			// when the grid has no columns, we still need to return 0 for index=0 and grid.Width for index=1
+			if (index == 0)
+				return 0;
+			else if (index < grid.ColumnDefinitions.Count)
 				return grid.ColumnDefinitions[index].Offset;
 			else
 				return grid.ActualWidth;
@@ -116,7 +119,9 @@ namespace ICSharpCode.WpfDesign.Designer.Extensions
 		
 		double GetRowOffset(int index)
 		{
-			if (index < grid.RowDefinitions.Count)
+			if (index == 0)
+				return 0;
+			else if (index < grid.RowDefinitions.Count)
 				return grid.RowDefinitions[index].Offset;
 			else
 				return grid.ActualHeight;

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/WpfDesign.Designer.csproj

@@ -71,6 +71,7 @@
     <Compile Include="Controls\ResizeThumb.cs" />
     <Compile Include="Controls\SingleVisualChildElement.cs" />
     <Compile Include="Controls\TypeEditors\BrushEditor.cs" />
+    <Compile Include="Controls\TypeEditors\ContentEditor.cs" />
     <Compile Include="Controls\WindowClone.cs" />
     <Compile Include="DesignPanel.cs" />
     <Compile Include="Extensions\GridAdornerProvider.cs" />

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.Designer/Project/Xaml/XamlDesignItem.cs

@@ -100,6 +100,14 @@ namespace ICSharpCode.WpfDesign.Designer.Xaml
 			}
 		}
 		
+		/// <summary>
+		/// Occurs when the parent of this design item changes.
+		/// </summary>
+		public override event EventHandler ParentChanged {
+			add    { _xamlObject.ParentPropertyChanged += value; }
+			remove { _xamlObject.ParentPropertyChanged += value; }
+		}
+		
 		public override UIElement View {
 			get {
 				if (_view != null)

src/AddIns/DisplayBindings/WpfDesign/WpfDesign.XamlDom/Project/XamlPropertyValue.cs

@@ -33,13 +33,23 @@ namespace ICSharpCode.WpfDesign.XamlDom
 		public XamlProperty ParentProperty {
 			get { return _parentProperty; }
 			internal set {
-				_parentProperty = value;
-				OnParentPropertyChanged();
+				if (_parentProperty != value) {
+					_parentProperty = value;
+					OnParentPropertyChanged();
+				}
 			}
 		}
 		
+		/// <summary>
+		/// Occurs when the value of the ParentProperty property changes.
+		/// </summary>
+		public event EventHandler ParentPropertyChanged;
+		
 		internal virtual void OnParentPropertyChanged()
 		{
+			if (ParentPropertyChanged != null) {
+				ParentPropertyChanged(this, EventArgs.Empty);
+			}
 		}
 		
 		internal abstract void RemoveNodeFromParent();

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/DesignItem.cs

@@ -48,6 +48,11 @@ namespace ICSharpCode.WpfDesign
 		/// </summary>
 		public abstract DesignItem Parent { get; }
 		
+		/// <summary>
+		/// Occurs when the parent of this design item changes.
+		/// </summary>
+		public abstract event EventHandler ParentChanged;
+		
 		/// <summary>
 		/// Gets the property where this DesignItem is used as a value.
 		/// </summary>

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/Extensions/ExtensionManager.cs

@@ -41,7 +41,9 @@ namespace ICSharpCode.WpfDesign.Extensions
 		void ReapplyExtensions(IEnumerable<DesignItem> items, ExtensionServer server)
 		{
 			foreach (DesignItem item in items) {
-				item.ReapplyExtensionServer(this, server);
+				if (item != null) {
+					item.ReapplyExtensionServer(this, server);
+				}
 			}
 		}
 		

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/Extensions/SelectionExtensionServer.cs

@@ -96,8 +96,6 @@ namespace ICSharpCode.WpfDesign.Extensions
 	/// </summary>
 	public class PrimarySelectionParentExtensionServer : DefaultExtensionServer
 	{
-		DesignItem oldPrimarySelectionParent;
-		
 		/// <summary>
 		/// Is called after the extension server is initialized and the Context property has been set.
 		/// </summary>
@@ -107,30 +105,32 @@ namespace ICSharpCode.WpfDesign.Extensions
 			this.Services.Selection.PrimarySelectionChanged += OnPrimarySelectionChanged;
 		}
 		
-		DesignItem PrimarySelectionParent {
-			get {
-				DesignItem newPrimarySelection = this.Services.Selection.PrimarySelection;
+		DesignItem primarySelection;
+		DesignItem primarySelectionParent;
+		
+		void OnPrimarySelectionChanged(object sender, EventArgs e)
+		{
+			DesignItem newPrimarySelection = this.Services.Selection.PrimarySelection;
+			if (primarySelection != newPrimarySelection) {
+				if (primarySelection != null) {
+					primarySelection.ParentChanged -= OnParentChanged;
+				}
 				if (newPrimarySelection != null) {
-					return newPrimarySelection.Parent;
-				} else {
-					return null;
+					newPrimarySelection.ParentChanged += OnParentChanged;
 				}
+				primarySelection = newPrimarySelection;
+				OnParentChanged(sender, e);
 			}
 		}
 		
-		void OnPrimarySelectionChanged(object sender, EventArgs e)
+		void OnParentChanged(object sender, EventArgs e)
 		{
-			DesignItem newPrimarySelectionParent = PrimarySelectionParent;
+			DesignItem newPrimarySelectionParent = primarySelection != null ? primarySelection.Parent : null;
 			
-			if (oldPrimarySelectionParent != newPrimarySelectionParent) {
-				if (oldPrimarySelectionParent == null) {
-					ReapplyExtensions(new DesignItem[] { newPrimarySelectionParent });
-				} else if (newPrimarySelectionParent == null) {
-					ReapplyExtensions(new DesignItem[] { oldPrimarySelectionParent });
-				} else {
-					ReapplyExtensions(new DesignItem[] { oldPrimarySelectionParent, newPrimarySelectionParent });
-				}
-				oldPrimarySelectionParent = newPrimarySelectionParent;
+			if (primarySelectionParent != newPrimarySelectionParent) {
+				DesignItem oldPrimarySelectionParent = primarySelectionParent;
+				primarySelectionParent = newPrimarySelectionParent;
+				ReapplyExtensions(new DesignItem[] { oldPrimarySelectionParent, newPrimarySelectionParent });
 			}
 		}
 		
@@ -139,7 +139,7 @@ namespace ICSharpCode.WpfDesign.Extensions
 		/// </summary>
 		public override bool ShouldApplyExtensions(DesignItem extendedItem)
 		{
-			return PrimarySelectionParent == extendedItem;
+			return primarySelectionParent == extendedItem;
 		}
 	}
 }

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PlacementOperation.cs

@@ -159,7 +159,8 @@ namespace ICSharpCode.WpfDesign
 					info.OriginalBounds = op.currentContainerBehavior.GetPosition(op, info.Item);
 					info.Bounds = info.OriginalBounds;
 				}
-			} catch {
+			} catch (Exception ex) {
+				Debug.WriteLine(ex.ToString());
 				op.changeGroup.Abort();
 				throw;
 			}

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PropertyEditor/DesignItemDataSource.cs

@@ -150,5 +150,17 @@ namespace ICSharpCode.WpfDesign.PropertyEditor
 		public ServiceContainer Services {
 			get { return item.Services; }
 		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataSource"/></summary>
+		public Brush CreateThumbnailBrush()
+		{
+			if (item.View != null) {
+				VisualBrush b = new VisualBrush(item.View);
+				b.AutoLayoutContent = false;
+				return b;
+			} else {
+				return null;
+			}
+		}
 	}
 }

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PropertyEditor/FallbackEditor.cs

@@ -44,20 +44,24 @@ namespace ICSharpCode.WpfDesign.PropertyEditor
 			} else {
 				this.FontWeight = FontWeights.Regular;
 			}
-			object val = property.Value;
-			if (val == null) {
-				this.Text = "null";
-				this.FontStyle = FontStyles.Italic;
+			if (property.IsAmbiguous) {
+				this.Text = "";
 			} else {
-				this.FontStyle = FontStyles.Normal;
-				try {
-					this.Text = val.ToString();
-				} catch (Exception ex) {
-					this.FontWeight = FontWeights.Regular;
-					Inlines.Clear();
-					Inlines.Add(new Italic(new Run(ex.GetType().Name)));
-					Inlines.Add(" ");
-					Inlines.Add(ex.Message);
+				object val = property.Value;
+				if (val == null) {
+					this.Text = "null";
+					this.FontStyle = FontStyles.Italic;
+				} else {
+					this.FontStyle = FontStyles.Normal;
+					try {
+						this.Text = val.ToString();
+					} catch (Exception ex) {
+						this.FontWeight = FontWeights.Regular;
+						Inlines.Clear();
+						Inlines.Add(new Italic(new Run(ex.GetType().Name)));
+						Inlines.Add(" ");
+						Inlines.Add(ex.Message);
+					}
 				}
 			}
 		}

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PropertyEditor/IPropertyEditorDataSource.cs

@@ -52,6 +52,11 @@ namespace ICSharpCode.WpfDesign.PropertyEditor
 		/// Gets the service container attached to this data source.
 		/// </summary>
 		ServiceContainer Services { get; }
+		
+		/// <summary>
+		/// Gets a brush used as a preview for the data source.
+		/// </summary>
+		Brush CreateThumbnailBrush();
 	}
 	
 	/// <summary>

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PropertyEditor/MultipleSelectionDataSource.cs

@@ -7,6 +7,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Windows.Media;
 
 namespace ICSharpCode.WpfDesign.PropertyEditor
 {
@@ -127,5 +128,11 @@ namespace ICSharpCode.WpfDesign.PropertyEditor
 		public ServiceContainer Services {
 			get { return services; }
 		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataSource"/></summary>
+		public Brush CreateThumbnailBrush()
+		{
+			return null;
+		}
 	}
 }

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PropertyEditor/ProxyPropertyEditorDataProperty.cs

@@ -0,0 +1,109 @@
+// <file>
+//     <copyright see="prj:///doc/copyright.txt"/>
+//     <license see="prj:///doc/license.txt"/>
+//     <owner name="Daniel Grunwald" email="daniel@danielgrunwald.de"/>
+//     <version>$Revision$</version>
+// </file>
+
+using System;
+
+namespace ICSharpCode.WpfDesign.PropertyEditor
+{
+	/// <summary>
+	/// Implements IPropertyEditorDataProperty by forwarding all calls to another IPropertyEditorDataProperty.
+	/// </summary>
+	public abstract class ProxyPropertyEditorDataProperty : IPropertyEditorDataProperty
+	{
+		readonly IPropertyEditorDataProperty data;
+		
+		/// <summary></summary>
+		protected ProxyPropertyEditorDataProperty(IPropertyEditorDataProperty data)
+		{
+			if (data == null)
+				throw new ArgumentNullException("data");
+			this.data = data;
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual event EventHandler IsSetChanged {
+			add    { data.IsSetChanged += value; }
+			remove { data.IsSetChanged -= value; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual event EventHandler ValueChanged {
+			add    { data.ValueChanged += value; }
+			remove { data.ValueChanged -= value; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual IPropertyEditorDataSource OwnerDataSource {
+			get { return data.OwnerDataSource; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual string Category {
+			get { return data.Category; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual string Name {
+			get { return data.Name; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual Type ReturnType {
+			get { return data.ReturnType; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual Type DeclaringType {
+			get { return data.DeclaringType; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual System.ComponentModel.TypeConverter TypeConverter {
+			get { return data.TypeConverter; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual bool IsSet {
+			get { return data.IsSet; }
+			set { data.IsSet = value; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual bool IsAmbiguous {
+			get { return data.IsAmbiguous; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual object Value {
+			get { return data.Value; }
+			set { data.Value = value; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual bool CanUseCustomExpression {
+			get { return data.CanUseCustomExpression; }
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual object GetDescription()
+		{
+			return data.GetDescription();
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual void SetCustomExpression(string expression)
+		{
+			data.SetCustomExpression(expression);
+		}
+		
+		/// <summary>See <see cref="IPropertyEditorDataProperty"/></summary>
+		public virtual System.Windows.UIElement CreateEditor()
+		{
+			return data.CreateEditor();
+		}
+	}
+}

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/PropertyEditor/TextBoxEditor.cs

@@ -22,7 +22,7 @@ namespace ICSharpCode.WpfDesign.PropertyEditor
 	/// <summary>
 	/// Type editor used to edit properties using a text box and the type's default type converter.
 	/// </summary>
-	sealed class TextBoxEditor : TextBox
+	public sealed class TextBoxEditor : TextBox
 	{
 		readonly IPropertyEditorDataProperty property;
 		bool isDirty;
@@ -33,6 +33,9 @@ namespace ICSharpCode.WpfDesign.PropertyEditor
 		/// </summary>
 		public TextBoxEditor(IPropertyEditorDataProperty property)
 		{
+			if (property == null)
+				throw new ArgumentNullException("property");
+			
 			this.property = property;
 			UpdateFromSource();
 			PropertyEditorBindingHelper.AddValueChangedEventHandler(

src/AddIns/DisplayBindings/WpfDesign/WpfDesign/Project/WpfDesign.csproj

@@ -90,6 +90,7 @@
     <Compile Include="PlacementType.cs" />
     <Compile Include="PropertyEditor\BooleanEditor.cs" />
     <Compile Include="PropertyEditor\MultipleSelectionDataProperty.cs" />
+    <Compile Include="PropertyEditor\ProxyPropertyEditorDataProperty.cs" />
     <Compile Include="PropertyEditor\StandardValuesComboBoxEditor.cs" />
     <Compile Include="PropertyEditor\DesignItemDataProperty.cs" />
     <Compile Include="PropertyEditor\DesignItemDataSource.cs" />