[Mac] Initial Events implementation.dominique-Events

27 files changed, 538 insertions, 261 deletions

diff --git a/Xamarin.PropertyEditing.Mac/BaseOutlineList.cs b/Xamarin.PropertyEditing.Mac/BaseOutlineList.cs
new file mode 100644
index 0000000..a1f9a34
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/BaseOutlineList.cs
@@ -0,0 +1,84 @@
+using System;
+using AppKit;
+using CoreGraphics;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal abstract class BaseOutlineList
+		: NSView
+	{
+		private IHostResourceProvider hostResources;
+		private readonly NSOutlineView outlineViewTable;
+		private readonly NSScrollView scrollView;
+		protected PanelViewModel viewModel;
+		public NSOutlineView OutlineViewTable => this.outlineViewTable;
+		protected BaseOutlineViewDataSource dataSource;
+
+		public IHostResourceProvider HostResourceProvider
+		{
+			get => this.hostResources;
+			set {
+				if (this.hostResources == value)
+					return;
+				if (value == null)
+					throw new ArgumentNullException (nameof (value), "Cannot set HostResourceProvider to null");
+
+				this.hostResources = value;
+				UpdateResourceProvider ();
+			}
+		}
+
+		public virtual PanelViewModel ViewModel {
+			get => this.viewModel;
+			set {
+				this.viewModel = value;
+			}
+		}
+
+		internal BaseOutlineList (IHostResourceProvider hostResources, string columnID)
+		{
+			if (hostResources == null)
+				throw new ArgumentNullException (nameof (hostResources));
+
+			if (columnID == null)
+				throw new ArgumentNullException (nameof (columnID));
+
+			this.hostResources = hostResources;
+
+			this.outlineViewTable = new FirstResponderOutlineView {
+				IndentationPerLevel = 0,
+				SelectionHighlightStyle = NSTableViewSelectionHighlightStyle.None,
+				HeaderView = null,
+				IntercellSpacing = new CGSize (0, 0)
+			};
+
+			var outlineViewColumn = new NSTableColumn (columnID);
+			this.outlineViewTable.AddColumn (outlineViewColumn);
+
+			this.scrollView = new NSScrollView {
+				AutoresizingMask = NSViewResizingMask.WidthSizable | NSViewResizingMask.HeightSizable,
+				HasHorizontalScroller = false,
+				HasVerticalScroller = true,
+			};
+
+			this.scrollView.DocumentView = this.outlineViewTable;
+			AddSubview (this.scrollView);
+		}
+
+		public sealed override void ViewDidChangeEffectiveAppearance ()
+		{
+			base.ViewDidChangeEffectiveAppearance ();
+
+			UpdateResourceProvider ();
+		}
+
+		protected virtual void UpdateResourceProvider ()
+		{
+			if (this.outlineViewTable == null || this.hostResources == null)
+				return;
+
+			this.outlineViewTable.BackgroundColor = this.hostResources.GetNamedColor (NamedResources.PadBackgroundColor);
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing.Mac/BaseOutlineViewDataSource.cs b/Xamarin.PropertyEditing.Mac/BaseOutlineViewDataSource.cs
new file mode 100644
index 0000000..2657222
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/BaseOutlineViewDataSource.cs
@@ -0,0 +1,43 @@
+using System;
+using System.Collections.Generic;
+using AppKit;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class BaseOutlineViewDataSource
+		: NSOutlineViewDataSource
+	{
+		internal bool Filtering => !string.IsNullOrEmpty (DataContext.FilterText);
+		internal PanelViewModel DataContext { get; }
+
+		internal Dictionary<object, NSObjectFacade> GroupFacades { get; }
+
+		internal BaseOutlineViewDataSource (PanelViewModel panelViewModel)
+		{
+			if (panelViewModel == null)
+				throw new ArgumentNullException (nameof (panelViewModel));
+
+			DataContext = panelViewModel;
+			GroupFacades = new Dictionary<object, NSObjectFacade> ();
+		}
+
+		internal bool TryGetFacade (object element, out NSObjectFacade facade)
+		{
+			return GroupFacades.TryGetValue (element, out facade);
+		}
+
+		internal NSObjectFacade GetFacade (object element)
+		{
+			NSObjectFacade facade;
+			if (element is PanelGroupViewModel) {
+				if (!GroupFacades.TryGetValue (element, out facade)) {
+					GroupFacades[element] = facade = new NSObjectFacade (element);
+				}
+			} else
+				facade = new NSObjectFacade (element);
+
+			return facade;
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/BaseOutlineViewDelegate.cs b/Xamarin.PropertyEditing.Mac/BaseOutlineViewDelegate.cs
new file mode 100644
index 0000000..63aef93
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/BaseOutlineViewDelegate.cs
@@ -0,0 +1,23 @@
+using System;
+using AppKit;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class BaseOutlineViewDelegate
+		: NSOutlineViewDelegate
+	{
+		internal IHostResourceProvider HostResources { get; }
+        internal BaseOutlineViewDataSource DataSource { get; }
+
+        public BaseOutlineViewDelegate (IHostResourceProvider hostResources, BaseOutlineViewDataSource dataSource)
+		{
+			if (hostResources == null)
+				throw new ArgumentNullException (nameof (hostResources));
+			if (dataSource == null)
+				throw new ArgumentNullException (nameof (dataSource));
+
+			HostResources = hostResources;
+			DataSource = dataSource;
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/Controls/CollectionEditorControl.cs b/Xamarin.PropertyEditing.Mac/Controls/CollectionEditorControl.cs
index 27297e3..c464205 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/CollectionEditorControl.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/CollectionEditorControl.cs
@@ -108,8 +108,7 @@ namespace Xamarin.PropertyEditing.Mac
 			controlsBorder.AddSubview (addBorder);
 			controlsBorder.AddSubview (removeBorder);
 
-			this.propertyList = new PropertyList {
-				HostResourceProvider = hostResources,
+			this.propertyList = new PropertyList (hostResources, PropertyEditorPanel.PropertyEditorColId) {
 				ShowHeader = false,
 			};
 
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs
index c621392..82acd29 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/PropertyButton.cs
@@ -40,17 +40,11 @@ namespace Xamarin.PropertyEditing.Mac
 			}
 		}
 
-		public PropertyButton (IHostResourceProvider hostResources)
+		public PropertyButton (IHostResourceProvider hostResources) : base (hostResources, "pe-property-button-default-mac-10")
 		{
-			if (hostResources == null)
-				throw new ArgumentNullException (nameof (hostResources));
-
-			this.hostResources = hostResources;
-
 			AccessibilityTitle = Properties.Resources.AccessibilityPropertiesButton;
 			AccessibilityHelp = Properties.Resources.AccessibilityPropertiesButtonDescription;
 			Enabled = true;
-			Image = this.hostResources.GetNamedImage ("pe-property-button-default-mac-10");
 			ImageScaling = NSImageScale.None;
 			ToolTip = Properties.Resources.Default;
 
@@ -69,20 +63,11 @@ namespace Xamarin.PropertyEditing.Mac
 			AppearanceChanged ();
 		}
 
-		public sealed override void ViewDidChangeEffectiveAppearance ()
-		{
-			base.ViewDidChangeEffectiveAppearance ();
-
-			AppearanceChanged ();
-		}
-
-		private void AppearanceChanged ()
+		protected override void AppearanceChanged ()
 		{
 			UpdateImage ();
 		}
 
-		private readonly IHostResourceProvider hostResources;
-
 		private void PopUpContextMenu ()
 		{
 			if (this.popUpContextMenu == null) {
@@ -175,34 +160,34 @@ namespace Xamarin.PropertyEditing.Mac
 			if (this.viewModel != null) {
 				
 				switch (this.viewModel.ValueSource) {
-				case ValueSource.Binding:
-					Image = focused ? this.hostResources.GetNamedImage ("pe-property-button-bound-mac-active-10") : this.hostResources.GetNamedImage ("pe-property-button-bound-mac-10");
-					break;
-
-				case ValueSource.Default:
-					Image = focused ? this.hostResources.GetNamedImage ("pe-property-button-default-mac-active-10") : this.hostResources.GetNamedImage ("pe-property-button-default-mac-10");
-					break;
-
-				case ValueSource.Local:
-					Image = focused ? this.hostResources.GetNamedImage ("pe-property-button-local-mac-active-10") : this.hostResources.GetNamedImage ("pe-property-button-local-mac-10");
-					break;
-
-				case ValueSource.Inherited:
-					Image = focused ? this.hostResources.GetNamedImage ("pe-property-button-inherited-mac-active-10") : this.hostResources.GetNamedImage ("pe-property-button-inherited-mac-10");
-					break;
-
-				case ValueSource.Resource:
-					Image = focused ? this.hostResources.GetNamedImage ("pe-property-button-inherited-mac-active-10") : this.hostResources.GetNamedImage ("pe-property-button-inherited-mac-10");
-					break;
-
-				case ValueSource.Unset:
-					Image = focused ? this.hostResources.GetNamedImage ("pe-property-button-default-mac-active-10") : this.hostResources.GetNamedImage ("pe-property-button-default-mac-10");
-					break;
-
-				default:
-					// To Handle ValueSource.DefaultStyle, ValueSource.Style etc.
-					Image = null;
-					break;
+					case ValueSource.Binding:
+						Image = focused ? HostResources.GetNamedImage ("pe-property-button-bound-mac-active-10") : HostResources.GetNamedImage ("pe-property-button-bound-mac-10");
+						break;
+
+					case ValueSource.Default:
+						Image = focused ? HostResources.GetNamedImage ("pe-property-button-default-mac-active-10") : HostResources.GetNamedImage ("pe-property-button-default-mac-10");
+						break;
+
+					case ValueSource.Local:
+						Image = focused ? HostResources.GetNamedImage ("pe-property-button-local-mac-active-10") : HostResources.GetNamedImage ("pe-property-button-local-mac-10");
+						break;
+
+					case ValueSource.Inherited:
+						Image = focused ? HostResources.GetNamedImage ("pe-property-button-inherited-mac-active-10") : HostResources.GetNamedImage ("pe-property-button-inherited-mac-10");
+						break;
+
+					case ValueSource.Resource:
+						Image = focused ? HostResources.GetNamedImage ("pe-property-button-inherited-mac-active-10") : HostResources.GetNamedImage ("pe-property-button-inherited-mac-10");
+						break;
+
+					case ValueSource.Unset:
+						Image = focused ? HostResources.GetNamedImage ("pe-property-button-default-mac-active-10") : HostResources.GetNamedImage ("pe-property-button-default-mac-10");
+						break;
+
+					default:
+						// To Handle ValueSource.DefaultStyle, ValueSource.Style etc.
+						Image = null;
+						break;
 				}
 			}
 		}
@@ -252,11 +237,11 @@ namespace Xamarin.PropertyEditing.Mac
 
 		private void OnCustomExpression (object sender, EventArgs e)
 		{
-			var customExpressionView = new CustomExpressionView (this.hostResources, viewModel) {
+			var customExpressionView = new CustomExpressionView (this.HostResources, viewModel) {
 				Appearance = EffectiveAppearance
 			};
 
-			var customExpressionPopOver = new AutoClosePopOver (this.hostResources, EffectiveAppearance) {
+			var customExpressionPopOver = new AutoClosePopOver (this.HostResources, EffectiveAppearance) {
 				CloseOnEnter = false,
 				ContentViewController = new NSViewController (null, null) { View = customExpressionView },
 			};
@@ -268,11 +253,11 @@ namespace Xamarin.PropertyEditing.Mac
 
 		private void OnResourceRequested (object sender, EventArgs e)
 		{
-			var requestResourceView = new RequestResourceView (this.hostResources, this.viewModel) {
+			var requestResourceView = new RequestResourceView (this.HostResources, this.viewModel) {
 				Appearance = EffectiveAppearance
 			};
 
-			var resourceSelectorPopOver = new AutoClosePopOver (this.hostResources, EffectiveAppearance) {
+			var resourceSelectorPopOver = new AutoClosePopOver (this.HostResources, EffectiveAppearance) {
 				ContentViewController = new NSViewController (null, null) { View = requestResourceView },
 			};
 
@@ -283,7 +268,7 @@ namespace Xamarin.PropertyEditing.Mac
 
 		private void OnBindingRequested (object sender, CreateBindingRequestedEventArgs e)
 		{
-			var bindingEditorWindow = new BindingEditorWindow (this.hostResources, this.viewModel) {
+			var bindingEditorWindow = new BindingEditorWindow (this.HostResources, this.viewModel) {
 				Appearance = EffectiveAppearance,
 			};
 
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs
index 2b82a62..5a55498 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/SpinnerButton.cs
@@ -19,12 +19,8 @@ namespace Xamarin.PropertyEditing.Mac
 			return base.HitTest (aPoint);
 		}
 
-		public SpinnerButton (IHostResourceProvider hostResource, bool isUp)
+		public SpinnerButton (IHostResourceProvider hostResource, bool isUp) : base (hostResource, "") // Blank because it is set up before AppearanceChanged is called
 		{
-			if (hostResource == null)
-				throw new ArgumentNullException (nameof (hostResource));
-
-			this.hostResources = hostResource;
 			this.imageBase += (isUp) ? "up" : "down";
 
 			AppearanceChanged ();
@@ -42,22 +38,14 @@ namespace Xamarin.PropertyEditing.Mac
 			UpdateImage ();
 		}
 
-		public sealed override void ViewDidChangeEffectiveAppearance ()
-		{
-			base.ViewDidChangeEffectiveAppearance ();
-
-			AppearanceChanged ();
-		}
-
-		private void AppearanceChanged ()
+		protected override void AppearanceChanged ()
 		{
-			this.image = this.hostResources.GetNamedImage (this.imageBase);
-			this.mouseOverImage = this.hostResources.GetNamedImage (this.imageBase + "-focus-blue");
+			this.image = HostResources.GetNamedImage (this.imageBase);
+			this.mouseOverImage = HostResources.GetNamedImage (this.imageBase + "-focus-blue");
 
 			UpdateImage ();
 		}
 
-		private readonly IHostResourceProvider hostResources;
 		private bool isMouseOver;
 		private string imageBase = "pe-stepper-";
 
diff --git a/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs b/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs
index e00482d..0316820 100644
--- a/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs
+++ b/Xamarin.PropertyEditing.Mac/Controls/Custom/UnfocusableButton.cs
@@ -3,17 +3,30 @@ using AppKit;
 
 namespace Xamarin.PropertyEditing.Mac
 {
-	public abstract class UnfocusableButton : NSImageView
+	public class UnfocusableButton : NSImageView
 	{
 		public event EventHandler OnMouseEntered;
 		public event EventHandler OnMouseExited;
 		public event EventHandler OnMouseLeftDown;
 		public event EventHandler OnMouseRightDown;
 
-		NSTrackingArea trackingArea;
+		private NSTrackingArea trackingArea;
 
-		public UnfocusableButton ()
+        internal IHostResourceProvider HostResources { get; }
+
+		private readonly string imageName;
+
+		internal UnfocusableButton (IHostResourceProvider hostResources, string imageName)
 		{
+			if (hostResources == null)
+				throw new ArgumentNullException (nameof (hostResources));
+
+			if (imageName == null)
+				throw new ArgumentNullException (nameof (imageName));
+
+			HostResources = hostResources;
+			this.imageName = imageName;
+		
 			Enabled = true;
 			ImageScaling = NSImageScale.AxesIndependently;
 		}
@@ -62,6 +75,13 @@ namespace Xamarin.PropertyEditing.Mac
 				AddTrackingArea (trackingArea);
 			}
 		}
+
+		public sealed override void ViewDidChangeEffectiveAppearance ()
+		{
+			base.ViewDidChangeEffectiveAppearance ();
+
+			AppearanceChanged ();
+		}
 		#endregion
 
 
@@ -86,6 +106,10 @@ namespace Xamarin.PropertyEditing.Mac
 			OnMouseRightDown?.Invoke (this, EventArgs.Empty);
 		}
 
+		protected virtual void AppearanceChanged ()
+		{
+			Image = HostResources.GetNamedImage (this.imageName);
+		}
 		#endregion
 	}
 }
diff --git a/Xamarin.PropertyEditing.Mac/EventList.cs b/Xamarin.PropertyEditing.Mac/EventList.cs
new file mode 100644
index 0000000..dae5a63
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/EventList.cs
@@ -0,0 +1,44 @@
+using System;

+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class EventList
+		: BaseOutlineList
+	{
+		public EventList (IHostResourceProvider hostResources, string columnID) : base (hostResources, columnID)
+		{
+		}
+
+		public override PanelViewModel ViewModel
+		{
+			set {
+				if (this.viewModel != null) {
+					OutlineViewTable.Delegate = null;
+					OutlineViewTable.DataSource = null;
+				}
+
+				this.viewModel = value;
+
+				if (this.viewModel != null) {
+					this.dataSource = new EventTableDataSource (this.viewModel);
+					OutlineViewTable.Delegate = new EventTableDelegate (HostResourceProvider, this.dataSource);
+					OutlineViewTable.DataSource = this.dataSource;
+				}
+			}
+		}
+
+		protected override void UpdateResourceProvider ()
+		{
+			base.UpdateResourceProvider ();
+
+			if (OutlineViewTable.Delegate == null)
+				OutlineViewTable.Delegate = new EventTableDelegate (HostResourceProvider, this.dataSource);
+		}
+
+		internal void ReloadDate ()
+		{
+			OutlineViewTable.ReloadData ();
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing.Mac/EventTableDataSource.cs b/Xamarin.PropertyEditing.Mac/EventTableDataSource.cs
new file mode 100644
index 0000000..2255257
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/EventTableDataSource.cs
@@ -0,0 +1,29 @@
+using System;

+using AppKit;

+using Foundation;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class EventTableDataSource : BaseOutlineViewDataSource
+	{
+		public EventTableDataSource (PanelViewModel panelVm) : base (panelVm)
+		{
+		}
+
+		public override nint GetChildrenCount (NSOutlineView outlineView, NSObject item)
+		{
+			return DataContext.Events.Count;
+		}
+
+		public override NSObject GetChild (NSOutlineView outlineView, nint childIndex, NSObject item)
+		{
+			return GetFacade (DataContext.Events.ElementAt ((int)childIndex));
+		}
+
+		public override bool ItemExpandable (NSOutlineView outlineView, NSObject item)
+		{
+			return false;
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing.Mac/EventTableDelegate.cs b/Xamarin.PropertyEditing.Mac/EventTableDelegate.cs
new file mode 100644
index 0000000..15d080a
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/EventTableDelegate.cs
@@ -0,0 +1,53 @@
+using System;

+using AppKit;
+using Foundation;
+using Xamarin.PropertyEditing.ViewModels;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class EventTableDelegate : BaseOutlineViewDelegate
+	{
+		public const string EventIdentifier = "EventContainer";
+
+		public EventTableDelegate (IHostResourceProvider hostResources, BaseOutlineViewDataSource dataSource) : base (hostResources, dataSource)
+		{
+		}
+
+		public override NSView GetView (NSOutlineView outlineView, NSTableColumn tableColumn, NSObject item)
+		{
+			if (item is NSObjectFacade facade) {
+				if (facade.Target is EventViewModel eventViewModel) {
+					var viewContainer = (NSView)outlineView.MakeView (EventIdentifier, this);
+					if (viewContainer == null) {
+						viewContainer = new NSView {
+							Identifier = EventIdentifier,
+						};
+
+						var title = new UnfocusableTextField {
+							Font = NSFont.FromFontName (PropertyEditorControl.DefaultFontName, PropertyEditorControl.DefaultDescriptionLabelFontSize),
+							TranslatesAutoresizingMaskIntoConstraints = false,
+							StringValue = eventViewModel.Name,
+						};
+						viewContainer.AddSubview (title);
+
+						viewContainer.AddConstraints (new[] {
+							NSLayoutConstraint.Create (title, NSLayoutAttribute.CenterY, NSLayoutRelation.Equal, viewContainer, NSLayoutAttribute.CenterY, 1, 0),
+							NSLayoutConstraint.Create (title, NSLayoutAttribute.Left, NSLayoutRelation.Equal, viewContainer,  NSLayoutAttribute.Left, 1f, 0f),
+							NSLayoutConstraint.Create (title, NSLayoutAttribute.Right, NSLayoutRelation.Equal, viewContainer,  NSLayoutAttribute.Right, 1f, -10f),
+							NSLayoutConstraint.Create (title, NSLayoutAttribute.Height, NSLayoutRelation.Equal, viewContainer, NSLayoutAttribute.Height, 1, 0),
+						});
+					}
+
+					return viewContainer;
+				}
+			}
+
+			return null;
+		}
+
+		public override nfloat GetRowHeight (NSOutlineView outlineView, NSObject item)
+		{
+			return 24f;
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing.Mac/FirstResponderOutlineView.cs b/Xamarin.PropertyEditing.Mac/FirstResponderOutlineView.cs
new file mode 100644
index 0000000..2dfe76a
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/FirstResponderOutlineView.cs
@@ -0,0 +1,40 @@
+using System;
+using AppKit;
+
+namespace Xamarin.PropertyEditing.Mac
+{
+	internal class FirstResponderOutlineView : NSOutlineView
+	{
+		private bool tabbedIn;
+		public override bool ValidateProposedFirstResponder (NSResponder responder, NSEvent forEvent)
+		{
+			return true;
+		}
+
+		public override bool BecomeFirstResponder ()
+		{
+			var willBecomeFirstResponder = base.BecomeFirstResponder ();
+			if (willBecomeFirstResponder) {
+				if (SelectedRows.Count == 0 && RowCount > 0) {
+					SelectRow (0, false);
+					this.tabbedIn = true;
+					var row = GetRowView ((nint)SelectedRows.FirstIndex, false);
+					return Window.MakeFirstResponder (row.NextValidKeyView);
+				}
+			}
+			this.tabbedIn = false;
+			return willBecomeFirstResponder;
+		}
+
+		public override bool ResignFirstResponder ()
+		{
+			var wilResignFirstResponder = base.ResignFirstResponder ();
+			if (wilResignFirstResponder) {
+				if (SelectedRows.Count > 0 && !this.tabbedIn) {
+					DeselectRow ((nint)SelectedRows.FirstIndex);
+				}
+			}
+			return wilResignFirstResponder;
+		}
+	}
+}
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator.png
new file mode 100644
index 0000000..438b639
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator@2x.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator@2x.png
new file mode 100644
index 0000000..31f56cc
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator~dark.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator~dark.png
new file mode 100644
index 0000000..438b639
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator~dark.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator~dark@2x.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator~dark@2x.png
new file mode 100644
index 0000000..31f56cc
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-header-separator~dark@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16.png
new file mode 100644
index 0000000..13368d5
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16@2x.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16@2x.png
new file mode 100644
index 0000000..a992b32
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16~dark.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16~dark.png
new file mode 100644
index 0000000..8a03423
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16~dark.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16~dark@2x.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16~dark@2x.png
new file mode 100644
index 0000000..ab9ddfc
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-events-16~dark@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16.png
new file mode 100644
index 0000000..894575e
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16@2x.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16@2x.png
new file mode 100644
index 0000000..fa4507f
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16~dark.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16~dark.png
new file mode 100644
index 0000000..de6c960
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16~dark.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16~dark@2x.png b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16~dark@2x.png
new file mode 100644
index 0000000..fea871a
--- /dev/null
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditingResource/Contents/Resources/pe-show-properties-16~dark@2x.png
diff --git a/Xamarin.PropertyEditing.Mac/PropertyEditorPanel.cs b/Xamarin.PropertyEditing.Mac/PropertyEditorPanel.cs
index 1463c48..02871a8 100644
--- a/Xamarin.PropertyEditing.Mac/PropertyEditorPanel.cs
+++ b/Xamarin.PropertyEditing.Mac/PropertyEditorPanel.cs
@@ -87,11 +87,14 @@ namespace Xamarin.PropertyEditing.Mac
 				if (this.viewModel != null) {
 					this.viewModel.PropertyChanged -= OnVmPropertyChanged;
 
-					var views = this.tabStack.Views;
-					for (int i = 0; i < views.Length; i++) {
-						var button = (TabButton)views[i];
-						button.Clicked -= OnArrangeModeChanged;
-						button.RemoveFromSuperview ();
+					var arrangeModeViews = this.arrangeModeTabStack.Views;
+					for (int i = 0; i < arrangeModeViews.Length; i++) {
+						((TabButton)arrangeModeViews[i]).Clicked -= OnArrangeModeChanged;
+					}
+
+					var propertiesEventsViews = this.propertiesEventsTabStack.Views;
+					for (int i = 0; i < propertiesEventsViews.Length; i++) {
+						((TabButton)propertiesEventsViews[i]).Clicked -= OnPropertiesEventsChanged;
 					}
 				}
 
@@ -114,12 +117,14 @@ namespace Xamarin.PropertyEditing.Mac
 
 						arrangeMode.Clicked += OnArrangeModeChanged;
 
-						this.tabStack.AddView (arrangeMode, NSStackViewGravity.Top);
+						this.arrangeModeTabStack.AddView (arrangeMode, NSStackViewGravity.Top);
 					}
 				}
 			}
 		}
 
+		
+
 		public ICollection<object> SelectedItems => this.viewModel.SelectedObjects;
 
 		public void Select (IEnumerable<object> selectedItems)
@@ -137,9 +142,14 @@ namespace Xamarin.PropertyEditing.Mac
 		private PanelViewModel viewModel;
 
 		private NSSearchField propertyFilter;
-		private NSStackView tabStack;
+		private NSStackView arrangeModeTabStack;
+		private NSStackView propertiesEventsTabStack;
 		private DynamicBox header, border;
 
+		private EventList eventList;
+		internal const string PropertyEditorColId = "PropertyEditors";
+		internal const string EventEditorColId = "EventEditors";
+
 		private void Initialize ()
 		{
 			this.header = new DynamicBox (HostResourceProvider, NamedResources.PanelTabBackground) {
@@ -161,29 +171,41 @@ namespace Xamarin.PropertyEditing.Mac
 
 			this.propertyFilter.Changed += OnPropertyFilterChanged;
 
-			this.tabStack = new NSStackView {
+			this.arrangeModeTabStack = new NSStackView {
 				Orientation = NSUserInterfaceLayoutOrientation.Horizontal,
 				TranslatesAutoresizingMaskIntoConstraints = false,
 				EdgeInsets = new NSEdgeInsets (0, 0, 0, 0)
 			};
 
-			((NSView)this.header.ContentView).AddSubview (this.tabStack);
+			((NSView)this.header.ContentView).AddSubview (this.arrangeModeTabStack);
 
-			this.propertyList = new PropertyList {
-				HostResourceProvider = this.hostResources,
+			this.propertiesEventsTabStack = new NSStackView {
+				Orientation = NSUserInterfaceLayoutOrientation.Horizontal,
+				TranslatesAutoresizingMaskIntoConstraints = false,
+				EdgeInsets = new NSEdgeInsets (0, 0, 0, 0)
+			};
+
+			((NSView)this.header.ContentView).AddSubview (this.propertiesEventsTabStack);
+
+			this.propertyList = new PropertyList (this.hostResources, PropertyEditorColId) {
 				TranslatesAutoresizingMaskIntoConstraints = false
 			};
 			AddSubview (this.propertyList);
 
-			this.AddConstraints (new[] {
+			AddConstraints (new[] {
 				NSLayoutConstraint.Create (this.header, NSLayoutAttribute.Top, NSLayoutRelation.Equal, this, NSLayoutAttribute.Top, 1, 0),
 				NSLayoutConstraint.Create (this.header, NSLayoutAttribute.Width, NSLayoutRelation.Equal, this, NSLayoutAttribute.Width, 1, 0),
 				NSLayoutConstraint.Create (this.header, NSLayoutAttribute.Height, NSLayoutRelation.Equal, 1, 30),
 
-				NSLayoutConstraint.Create (this.tabStack, NSLayoutAttribute.Left, NSLayoutRelation.Equal, this.header,  NSLayoutAttribute.Left, 1, 0),
-				NSLayoutConstraint.Create (this.tabStack, NSLayoutAttribute.Top, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Top, 1, 0),
-				NSLayoutConstraint.Create (this.tabStack, NSLayoutAttribute.Bottom, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Bottom, 1, 0),
-				NSLayoutConstraint.Create (this.tabStack, NSLayoutAttribute.Right, NSLayoutRelation.LessThanOrEqual, this.propertyFilter, NSLayoutAttribute.Left, 1, 0),
+				NSLayoutConstraint.Create (this.arrangeModeTabStack, NSLayoutAttribute.Left, NSLayoutRelation.Equal, this.header,  NSLayoutAttribute.Left, 1, 0),
+				NSLayoutConstraint.Create (this.arrangeModeTabStack, NSLayoutAttribute.Top, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Top, 1, 0),
+				NSLayoutConstraint.Create (this.arrangeModeTabStack, NSLayoutAttribute.Bottom, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Bottom, 1, 0),
+				NSLayoutConstraint.Create (this.arrangeModeTabStack, NSLayoutAttribute.Right, NSLayoutRelation.LessThanOrEqual, this.propertiesEventsTabStack, NSLayoutAttribute.Left, 1, 0),
+
+				NSLayoutConstraint.Create (this.propertiesEventsTabStack, NSLayoutAttribute.Top, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Top, 1, 0),
+				NSLayoutConstraint.Create (this.propertiesEventsTabStack, NSLayoutAttribute.Bottom, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Bottom, 1, 0),
+				NSLayoutConstraint.Create (this.propertiesEventsTabStack, NSLayoutAttribute.Left, NSLayoutRelation.GreaterThanOrEqual, this.arrangeModeTabStack, NSLayoutAttribute.Right, 1, 0),
+				NSLayoutConstraint.Create (this.propertiesEventsTabStack, NSLayoutAttribute.Right, NSLayoutRelation.LessThanOrEqual, this.propertyFilter, NSLayoutAttribute.Left, 1, 0),
 
 				NSLayoutConstraint.Create (this.propertyFilter, NSLayoutAttribute.Right, NSLayoutRelation.Equal, this.header, NSLayoutAttribute.Right, 1, -15),
 				NSLayoutConstraint.Create (this.propertyFilter, NSLayoutAttribute.Width, NSLayoutRelation.Equal, 1, 150),
@@ -232,12 +254,55 @@ namespace Xamarin.PropertyEditing.Mac
 			if (e.PropertyName == nameof (PanelViewModel.ArrangeMode) || String.IsNullOrEmpty (e.PropertyName)) {
 				if (this.viewModel != null) {
 					int selected = this.viewModel.ArrangeModes.Select (vm => vm.ArrangeMode).IndexOf (this.viewModel.ArrangeMode);
-					var views = this.tabStack.Views;
+					var views = this.arrangeModeTabStack.Views;
 					for (int i = 0; i < views.Length; i++) {
-						((TabButton)views[i]).Selected = (i == selected);
+						((TabButton)views[i]).Selected = i == selected;
 					}
 				}
 			}
+
+			if (e.PropertyName == nameof (PanelViewModel.EventsEnabled)) {
+				if (this.viewModel.EventsEnabled) {
+					var sepButton = new UnfocusableButton (this.hostResources, "pe-header-separator");
+
+					this.propertiesEventsTabStack.AddView (sepButton, NSStackViewGravity.Top);
+
+					var properties = new TabButton (this.hostResources, "pe-show-properties-16") {
+						Bounds = new CGRect (0, 0, 32, 30),
+						Selected = true,
+						Tag = 0,
+						ToolTip = Properties.Resources.PropertiesSelectedElement,
+					};
+
+					properties.Clicked += OnPropertiesEventsChanged;
+
+					this.propertiesEventsTabStack.AddView (properties, NSStackViewGravity.Top);
+
+					var events = new TabButton (this.hostResources, "pe-show-events-16") {
+						Bounds = new CGRect (0, 0, 32, 30),
+						Tag = 1,
+						ToolTip = Properties.Resources.EventHandlersSelectedElement,
+					};
+
+					events.Clicked += OnPropertiesEventsChanged;
+
+					this.propertiesEventsTabStack.AddView (events, NSStackViewGravity.Top);
+
+					this.eventList = new EventList (this.hostResources, EventEditorColId) {
+						Hidden = true,
+						TranslatesAutoresizingMaskIntoConstraints = false,
+						ViewModel = this.viewModel,
+					};
+					AddSubview (this.eventList);
+
+					AddConstraints (new[]{
+						NSLayoutConstraint.Create (this.propertiesEventsTabStack, NSLayoutAttribute.Left, NSLayoutRelation.Equal, this.arrangeModeTabStack,  NSLayoutAttribute.Right, 1, 4),
+						NSLayoutConstraint.Create (this.eventList, NSLayoutAttribute.Top, NSLayoutRelation.Equal, this.border, NSLayoutAttribute.Bottom, 1, 0),
+						NSLayoutConstraint.Create (this.eventList, NSLayoutAttribute.Bottom, NSLayoutRelation.Equal, this, NSLayoutAttribute.Bottom, 1, 0),
+						NSLayoutConstraint.Create (this.eventList, NSLayoutAttribute.Width, NSLayoutRelation.Equal, this, NSLayoutAttribute.Width, 1, 0),
+					});
+				}
+			}
 		}
 
 		private string GetIconName (PropertyArrangeMode mode)
@@ -251,5 +316,32 @@ namespace Xamarin.PropertyEditing.Mac
 				throw new ArgumentException();
 			}
 		}
+
+		private void OnPropertiesEventsChanged (object sender, EventArgs e)
+		{
+			if (sender is TabButton tabButton) {
+				// Reset them all
+				NSView[] views = this.propertiesEventsTabStack.Views;
+				for (int i = 0; i < views.Length; i++) {
+					if (views[i] is TabButton tb) {
+						tb.Selected = false;
+					}
+				}
+
+				switch (tabButton.Tag) {
+					case 0:
+						this.propertyList.Hidden = false;
+						this.eventList.Hidden = true;
+						break;
+					case 1:
+						this.propertyList.Hidden = true;
+						this.eventList.Hidden = false;
+						this.eventList.ReloadDate ();
+						break;
+				}
+
+				tabButton.Selected = true;
+			}
+		}
 	}
-}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing.Mac/PropertyList.cs b/Xamarin.PropertyEditing.Mac/PropertyList.cs
index 06b76e5..40dae90 100644
--- a/Xamarin.PropertyEditing.Mac/PropertyList.cs
+++ b/Xamarin.PropertyEditing.Mac/PropertyList.cs
@@ -9,30 +9,10 @@ using Xamarin.PropertyEditing.ViewModels;
 namespace Xamarin.PropertyEditing.Mac
 {
 	internal class PropertyList
-		: NSView
+		: BaseOutlineList
 	{
-		internal const string PropertyEditorColId = "PropertyEditors";
-
-		public PropertyList ()
+		public PropertyList (IHostResourceProvider hostResources, string columnID) : base (hostResources, columnID)
 		{
-			this.propertyTable = new FirstResponderOutlineView {
-				IndentationPerLevel = 0,
-				SelectionHighlightStyle = NSTableViewSelectionHighlightStyle.None,
-				HeaderView = null,
-				IntercellSpacing = new CGSize (0, 0)
-			};
-
-			var propertyEditors = new NSTableColumn (PropertyEditorColId);
-			this.propertyTable.AddColumn (propertyEditors);
-
-			this.scrollView = new NSScrollView {
-				AutoresizingMask = NSViewResizingMask.WidthSizable | NSViewResizingMask.HeightSizable,
-				HasHorizontalScroller = false,
-				HasVerticalScroller = true,
-			};
-
-			this.scrollView.DocumentView = this.propertyTable;
-			AddSubview (this.scrollView);
 		}
 
 		public bool ShowHeader
@@ -44,23 +24,21 @@ namespace Xamarin.PropertyEditing.Mac
 					return;
 
 				this.showHeader = value;
-				if (this.dataSource != null) {
-					this.dataSource.ShowHeader = value;
-					this.propertyTable.ReloadData ();
+				if (this.dataSource != null && this.dataSource is PropertyTableDataSource propertyTableDataSource) {
+					propertyTableDataSource.ShowHeader = value;
+					OutlineViewTable.ReloadData ();
 				}
 			}
 		}
 
-		public PanelViewModel ViewModel
+		public override PanelViewModel ViewModel
 		{
-			get { return this.viewModel; }
-			set
-			{
+			set {
 				if (this.viewModel != null) {
 					this.viewModel.ArrangedPropertiesChanged -= OnPropertiesChanged;
 
-					this.propertyTable.Delegate = null;
-					this.propertyTable.DataSource = null;
+					OutlineViewTable.Delegate = null;
+					OutlineViewTable.DataSource = null;
 				}
 
 				this.viewModel = value;
@@ -69,97 +47,32 @@ namespace Xamarin.PropertyEditing.Mac
 					this.viewModel.ArrangedPropertiesChanged += OnPropertiesChanged;
 
 					this.dataSource = new PropertyTableDataSource (this.viewModel) { ShowHeader = ShowHeader };
-					this.propertyTable.Delegate = new PropertyTableDelegate (HostResourceProvider, this.dataSource);
-					this.propertyTable.DataSource = this.dataSource;
+					OutlineViewTable.Delegate = new PropertyTableDelegate (HostResourceProvider, this.dataSource);
+					OutlineViewTable.DataSource = this.dataSource;
 				}
 			}
 		}
 
-		public IHostResourceProvider HostResourceProvider
-		{
-			get => this.hostResources;
-			set
-			{
-				if (this.hostResources == value)
-					return;
-				if (value == null)
-					throw new ArgumentNullException (nameof (value), "Cannot set HostResourceProvider to null");
-
-				this.hostResources = value;
-				UpdateResourceProvider ();
-			}
-		}
-
-		public sealed override void ViewDidChangeEffectiveAppearance ()
-		{
-			base.ViewDidChangeEffectiveAppearance ();
-
-			UpdateResourceProvider ();
-		}
-
 		public void UpdateExpansions ()
 		{
-			((PropertyTableDelegate)this.propertyTable.Delegate).UpdateExpansions (this.propertyTable);
+			((PropertyTableDelegate)OutlineViewTable.Delegate).UpdateExpansions (OutlineViewTable);
 		}
 
-		private readonly NSOutlineView propertyTable;
-		private readonly NSScrollView scrollView;
-		private IHostResourceProvider hostResources;
-		private PropertyTableDataSource dataSource;
-		private PanelViewModel viewModel;
 		private bool showHeader = true;
 
-		private class FirstResponderOutlineView : NSOutlineView
-		{
-			private bool tabbedIn;
-			public override bool ValidateProposedFirstResponder (NSResponder responder, NSEvent forEvent)
-			{
-				return true;
-			}
-
-			public override bool BecomeFirstResponder ()
-			{
-				var willBecomeFirstResponder = base.BecomeFirstResponder ();
-				if (willBecomeFirstResponder) {
-					if (SelectedRows.Count == 0 && RowCount > 0) {
-						SelectRow (0, false);
-						this.tabbedIn = true;
-						var row = GetRowView ((nint)SelectedRows.FirstIndex, false);
-						return Window.MakeFirstResponder (row.NextValidKeyView);
-					}
-				}
-				this.tabbedIn = false;
-				return willBecomeFirstResponder;
-			}
-
-			public override bool ResignFirstResponder ()
-			{
-				var wilResignFirstResponder = base.ResignFirstResponder ();
-				if (wilResignFirstResponder) {
-					if (SelectedRows.Count > 0 && !this.tabbedIn) {
-						DeselectRow ((nint)SelectedRows.FirstIndex);
-					}
-				}
-				return wilResignFirstResponder;
-			}
-		}
-
 		private void OnPropertiesChanged (object sender, EventArgs e)
 		{
-			this.propertyTable.ReloadData ();
+			OutlineViewTable.ReloadData ();
 
-			((PropertyTableDelegate)this.propertyTable.Delegate).UpdateExpansions (this.propertyTable);
+			((PropertyTableDelegate)OutlineViewTable.Delegate).UpdateExpansions (OutlineViewTable);
 		}
 
-		private void UpdateResourceProvider ()
+		protected override void UpdateResourceProvider ()
 		{
-			if (this.propertyTable == null || this.hostResources == null)
-				return;
-
-			this.propertyTable.BackgroundColor = this.hostResources.GetNamedColor (NamedResources.PadBackgroundColor);
+			base.UpdateResourceProvider ();
 
-			if (this.propertyTable.Delegate != null)
-				this.propertyTable.Delegate = new PropertyTableDelegate (HostResourceProvider, this.dataSource);
+			if (OutlineViewTable.Delegate != null)
+				OutlineViewTable.Delegate = new PropertyTableDelegate (HostResourceProvider, this.dataSource);
 		}
 	}
-}
+}
\ No newline at end of file
diff --git a/Xamarin.PropertyEditing.Mac/PropertyTableDataSource.cs b/Xamarin.PropertyEditing.Mac/PropertyTableDataSource.cs
index 1a312e0..3906508 100644
--- a/Xamarin.PropertyEditing.Mac/PropertyTableDataSource.cs
+++ b/Xamarin.PropertyEditing.Mac/PropertyTableDataSource.cs
@@ -1,7 +1,5 @@
 using System;
-using System.Collections.Generic;
 using System.ComponentModel;
-using System.Linq;
 using AppKit;
 using Foundation;
 using Xamarin.PropertyEditing.ViewModels;
@@ -9,20 +7,12 @@ using Xamarin.PropertyEditing.ViewModels;
 namespace Xamarin.PropertyEditing.Mac
 {
 	internal class PropertyTableDataSource
-		: NSOutlineViewDataSource
+		: BaseOutlineViewDataSource
 	{
-		bool Filtering => !string.IsNullOrEmpty (this.vm.FilterText);
-
-		internal PropertyTableDataSource (PanelViewModel panelVm)
+		internal PropertyTableDataSource (PanelViewModel panelVm) : base(panelVm)
 		{
-			if (panelVm == null)
-				throw new ArgumentNullException (nameof (panelVm));
-
-			this.vm = panelVm;
 		}
 
-		public PanelViewModel DataContext => this.vm;
-
 		public bool ShowHeader
 		{
 			get;
@@ -31,7 +21,7 @@ namespace Xamarin.PropertyEditing.Mac
 
 		public override nint GetChildrenCount (NSOutlineView outlineView, NSObject item)
 		{
-			if (this.vm.ArrangedEditors.Count == 0)
+			if (DataContext.ArrangedEditors.Count == 0)
 				return 0;
 
 			var facade = (NSObjectFacade)item;
@@ -40,11 +30,11 @@ namespace Xamarin.PropertyEditing.Mac
 				
 			int headerCount = (ShowHeader && !Filtering) ? 1 : 0;
 
-			if (this.vm.ArrangeMode == PropertyArrangeMode.Name)
-				return this.vm.ArrangedEditors[0].Editors.Count + headerCount;
+			if (DataContext.ArrangeMode == PropertyArrangeMode.Name)
+				return DataContext.ArrangedEditors[0].Editors.Count + headerCount;
 			else {
 				if (item == null)
-					return this.vm.ArrangedEditors.Count + headerCount;
+					return DataContext.ArrangedEditors.Count + headerCount;
 				else {
 					var group = (PanelGroupViewModel)((NSObjectFacade)item).Target;
 					return group.Editors.Count + group.UncommonEditors.Count;
@@ -64,11 +54,11 @@ namespace Xamarin.PropertyEditing.Mac
 				element = ovm.ValueModel.Properties[(int)childIndex];
 			} else {
 				int headerCount = (ShowHeader && !Filtering) ? 1 : 0;
-				if (this.vm.ArrangeMode == PropertyArrangeMode.Name)
-					element = this.vm.ArrangedEditors[0].Editors[(int)childIndex - headerCount];
+				if (DataContext.ArrangeMode == PropertyArrangeMode.Name)
+					element = DataContext.ArrangedEditors[0].Editors[(int)childIndex - headerCount];
 				else {
 					if (item == null)
-						element = this.vm.ArrangedEditors[(int)childIndex - headerCount];
+						element = DataContext.ArrangedEditors[(int)childIndex - headerCount];
 					else {
 						var group = (PanelGroupViewModel)f.Target;
 						var list = group.Editors;
@@ -102,31 +92,10 @@ namespace Xamarin.PropertyEditing.Mac
 				return ovm.CanDelve;
 			}
 
-			if (this.vm.ArrangeMode == PropertyArrangeMode.Name)
+			if (DataContext.ArrangeMode == PropertyArrangeMode.Name)
 				return false;
 
 			return f.Target is PanelGroupViewModel;
 		}
-
-		public NSObjectFacade GetFacade (object element)
-		{
-			NSObjectFacade facade;
-			if (element is PanelGroupViewModel) {
-				if (!this.groupFacades.TryGetValue (element, out facade)) {
-					this.groupFacades[element] = facade = new NSObjectFacade (element);
-				}
-			} else
-				facade = new NSObjectFacade (element);
-
-			return facade;
-		}
-
-		public bool TryGetFacade (object element, out NSObjectFacade facade)
-		{
-			return this.groupFacades.TryGetValue (element, out facade);
-		}
-
-		private readonly PanelViewModel vm;
-		private readonly Dictionary<object, NSObjectFacade> groupFacades = new Dictionary<object, NSObjectFacade> ();
 	}
 }
diff --git a/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs b/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs
index 49f2665..80bd429 100644
--- a/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs
+++ b/Xamarin.PropertyEditing.Mac/PropertyTableDelegate.cs
@@ -10,32 +10,25 @@ using Xamarin.PropertyEditing.ViewModels;
 namespace Xamarin.PropertyEditing.Mac
 {
 	internal class PropertyTableDelegate
-		: NSOutlineViewDelegate
+		: BaseOutlineViewDelegate
 	{
-		public PropertyTableDelegate (IHostResourceProvider hostResources, PropertyTableDataSource dataSource)
+		public PropertyTableDelegate (IHostResourceProvider hostResources, BaseOutlineViewDataSource dataSource) : base (hostResources, dataSource)
 		{
-			if (hostResources == null)
-				throw new ArgumentNullException (nameof (hostResources));
-			if (dataSource == null)
-				throw new ArgumentNullException (nameof (dataSource));
-
-			this.hostResources = hostResources;
-			this.dataSource = dataSource;
 		}
 
 		public void UpdateExpansions (NSOutlineView outlineView)
 		{
 			this.isUpdatingExpansions = true;
 
-			if (!String.IsNullOrWhiteSpace (this.dataSource.DataContext.FilterText)) {
+			if (!String.IsNullOrWhiteSpace (DataSource.DataContext.FilterText)) {
 				outlineView.ExpandItem (null, true);
 			} else {
-				foreach (PanelGroupViewModel g in this.dataSource.DataContext.ArrangedEditors) {
+				foreach (PanelGroupViewModel g in DataSource.DataContext.ArrangedEditors) {
 					NSObjectFacade item;
-					if (!this.dataSource.TryGetFacade (g, out item))
+					if (!DataSource.TryGetFacade (g, out item))
 						continue;
 
-					if (this.dataSource.DataContext.GetIsExpanded (g.Category))
+					if (DataSource.DataContext.GetIsExpanded (g.Category))
 						EnsureOpenOrClose (outlineView, item, open: true);
 					else
 						EnsureOpenOrClose (outlineView, item, open: false);
@@ -74,7 +67,7 @@ namespace Xamarin.PropertyEditing.Mac
 
 				((UnfocusableTextField)labelContainer.Subviews[1]).StringValue = group.Category;
 
-				if (this.dataSource.DataContext.GetIsExpanded (group.Category)) {
+				if (DataSource.DataContext.GetIsExpanded (group.Category)) {
 					SynchronizationContext.Current.Post (s => {
 						outlineView.ExpandItem (item);
 					}, null);
@@ -86,7 +79,7 @@ namespace Xamarin.PropertyEditing.Mac
 			NSView editorOrContainer = null;
 			if (this.firstCache.TryGetValue (cellIdentifier, out IEditorView editor)) {
 				this.firstCache.Remove (cellIdentifier);
-				editorOrContainer = (editor.NativeView is PropertyEditorControl) ? new EditorContainer (this.hostResources, editor) { Identifier = cellIdentifier } : editor.NativeView;
+				editorOrContainer = (editor.NativeView is PropertyEditorControl) ? new EditorContainer (HostResources, editor) { Identifier = cellIdentifier } : editor.NativeView;
 			} else {
 				editorOrContainer = GetEditor (cellIdentifier, evm, outlineView);
 				editor = ((editorOrContainer as EditorContainer)?.EditorView) ?? editorOrContainer as IEditorView;
@@ -129,7 +122,7 @@ namespace Xamarin.PropertyEditing.Mac
 					outlineView.NoteHeightOfRowsWithIndexesChanged (new NSIndexSet (index));
 				}
 			} else if (editorOrContainer is PanelHeaderEditorControl header) {
-				header.ViewModel = this.dataSource.DataContext;
+				header.ViewModel = DataSource.DataContext;
 			}
 
 			return editorOrContainer;
@@ -155,7 +148,7 @@ namespace Xamarin.PropertyEditing.Mac
 			}
 
 			if (facade.Target is PanelGroupViewModel group)
-				this.dataSource.DataContext.SetIsExpanded (group.Category, isExpanded: true);
+				DataSource.DataContext.SetIsExpanded (group.Category, isExpanded: true);
 			else if (facade.Target is ObjectPropertyViewModel ovm) {
 				NSView view = outline.GetView (0, row, makeIfNecessary: false);
 				SetRowValueBackground (view, valueBackground: true);
@@ -177,7 +170,7 @@ namespace Xamarin.PropertyEditing.Mac
 			}
 
 			if (facade.Target is PanelGroupViewModel group)
-				this.dataSource.DataContext.SetIsExpanded (group.Category, isExpanded: false);
+				DataSource.DataContext.SetIsExpanded (group.Category, isExpanded: false);
 			else if (facade.Target is ObjectPropertyViewModel ovm) {
 				NSView view = outline.GetView (0, row, makeIfNecessary: false);
 				SetRowValueBackground (view, valueBackground: false);
@@ -238,11 +231,9 @@ namespace Xamarin.PropertyEditing.Mac
 
 		public const string CategoryIdentifier = "label";
 
-		private PropertyTableDataSource dataSource;
 		private bool isUpdatingExpansions;
 		private readonly PropertyEditorSelector editorSelector = new PropertyEditorSelector ();
 
-		private readonly IHostResourceProvider hostResources;
 		private readonly Dictionary<string, EditorRegistration> registrations = new Dictionary<string, EditorRegistration> ();
 		private readonly Dictionary<string, IEditorView> firstCache = new Dictionary<string, IEditorView> ();
 
@@ -270,7 +261,7 @@ namespace Xamarin.PropertyEditing.Mac
 				return;
 
 			if (valueBackground) {
-				var c = this.hostResources.GetNamedColor (NamedResources.ValueBlockBackgroundColor);
+				var c = HostResources.GetNamedColor (NamedResources.ValueBlockBackgroundColor);
 				view.SetValueForKey (c, new NSString ("backgroundColor"));
 			} else {
 				view.SetValueForKey (NSColor.Clear, new NSString ("backgroundColor"));
@@ -284,7 +275,7 @@ namespace Xamarin.PropertyEditing.Mac
 				return view;
 
 			if (vm != null) {
-				IEditorView editor = this.editorSelector.GetEditor (this.hostResources, vm);
+				IEditorView editor = this.editorSelector.GetEditor (HostResources, vm);
 
 				var editorControl = editor?.NativeView as PropertyEditorControl;
 				if (editorControl != null) {
@@ -294,9 +285,9 @@ namespace Xamarin.PropertyEditing.Mac
 					return editor.NativeView;
 				}
 
-				return new EditorContainer (this.hostResources, editor) { Identifier = identifier };
+				return new EditorContainer (HostResources, editor) { Identifier = identifier };
 			} else
-				return new PanelHeaderEditorControl (this.hostResources);
+				return new PanelHeaderEditorControl (HostResources);
 		}
 
 		private void GetVMGroupCellItendifiterFromFacade (NSObject item, out EditorViewModel vm, out PanelGroupViewModel group, out string cellIdentifier)