From 5b2f9d9b576f1009704d6d72a082c5b125699bcc Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jean-Philippe=20Bruy=C3=A8re?= <jp_bruyere@hotmail.com>
Date: Thu, 15 Apr 2021 05:33:39 +0200
Subject: [PATCH] save commit to find bug

---
 .../Templates/DefaultTableHeaderCell.template |   2 +
 Crow/Templates/MenuItem.template              |   2 +-
 Crow/src/IML/CompilerServices.cs              |   8 +-
 Crow/src/IML/Node.cs                          |   2 +-
 Crow/src/ItemTemplate.cs                      |   4 +-
 Crow/src/Widgets/Group.cs                     | 371 +++---------------
 Crow/src/Widgets/GroupBase.cs                 | 302 ++++++++++++++
 Crow/src/Widgets/Table copy.cs                | 259 ++++++++++++
 Crow/src/Widgets/Table.cs                     | 347 ++++++++++++----
 Crow/src/Widgets/TableRow copy.cs             | 321 +++++++++++++++
 Crow/src/Widgets/TableRow.cs                  | 288 +++++++-------
 Crow/src/Widgets/Widget.cs                    |  33 +-
 12 files changed, 1375 insertions(+), 564 deletions(-)
 create mode 100644 Crow/Templates/DefaultTableHeaderCell.template
 create mode 100644 Crow/src/Widgets/GroupBase.cs
 create mode 100644 Crow/src/Widgets/Table copy.cs
 create mode 100644 Crow/src/Widgets/TableRow copy.cs

diff --git a/Crow/Templates/DefaultTableHeaderCell.template b/Crow/Templates/DefaultTableHeaderCell.template
new file mode 100644
index 00000000..0bb5368b
--- /dev/null
+++ b/Crow/Templates/DefaultTableHeaderCell.template
@@ -0,0 +1,2 @@
+<?xml version="1.0"?>
+<Label RootDataLevel="true" Style="TableHeaderLabel" Text="{Caption}" Width="{Width}"/>
\ No newline at end of file
diff --git a/Crow/Templates/MenuItem.template b/Crow/Templates/MenuItem.template
index d5b39dd4..96adbd1e 100644
--- a/Crow/Templates/MenuItem.template
+++ b/Crow/Templates/MenuItem.template
@@ -1,7 +1,7 @@
 <?xml version="1.0"?>
 <ListItem>
 	<Popper Font="{./Font}" Caption="{./Caption}"  Background="{./Background}" PopDirection="{./PopDirection}"
-		Foreground = "{./Foreground}" CanPop="{./HasChildren}"
+		Foreground = "{./Foreground}" 
 		IsPopped="{²./IsOpened}" PopWidth="{./PopWidth}" PopHeight="{./PopHeight}">
 		<Template>
 			<CheckBox IsChecked="{²./IsPopped}" Caption="{./Caption}" Background="{./Background}" Foreground="{./Foreground}">
diff --git a/Crow/src/IML/CompilerServices.cs b/Crow/src/IML/CompilerServices.cs
index 644902f0..8d63bb8d 100644
--- a/Crow/src/IML/CompilerServices.cs
+++ b/Crow/src/IML/CompilerServices.cs
@@ -103,8 +103,8 @@ namespace Crow.IML
 		#region tree handling methods
 		internal static FieldInfo fiChild = typeof(PrivateContainer).GetField ("child", BindingFlags.Instance | BindingFlags.NonPublic);
 		internal static MethodInfo miSetChild = typeof (Container).GetMethod ("SetChild");
-		internal static MethodInfo miAddChild = typeof (Group).GetMethod ("AddChild");
-		internal static FieldInfo fiChildren = typeof(Group).GetField ("children", BindingFlags.Instance | BindingFlags.NonPublic);
+		internal static MethodInfo miAddChild = typeof (GroupBase).GetMethod ("AddChild");
+		internal static MethodInfo miGetChildren = typeof(GroupBase).GetProperty ("Children", BindingFlags.Instance | BindingFlags.Public).GetGetMethod();
 		internal static MethodInfo miLoadTmp = typeof (TemplatedControl).GetMethod ("loadTemplate", BindingFlags.Instance | BindingFlags.NonPublic);
 		internal static PropertyInfo piContent = typeof(TemplatedContainer).GetProperty ("Content");
 		internal static MethodInfo miAddItem = typeof (TemplatedGroup).GetMethod ("AddItem", BindingFlags.Instance | BindingFlags.Public);
@@ -504,8 +504,8 @@ namespace Crow.IML
 		/// <param name="parentType">Parent type</param>
 		/// <param name="index">Index of child, -1 for template root</param>
 		internal static void emitGetChild(ILGenerator il, Type parentType, int index){
-			if (typeof (Group).IsAssignableFrom (parentType)) {
-				il.Emit (OpCodes.Ldfld, fiChildren);
+			if (typeof (GroupBase).IsAssignableFrom (parentType)) {
+				il.Emit (OpCodes.Callvirt, miGetChildren);
 				il.Emit(OpCodes.Ldc_I4, index);
 				il.Emit (OpCodes.Callvirt, miGetGObjItem);
 				return;
diff --git a/Crow/src/IML/Node.cs b/Crow/src/IML/Node.cs
index 811cfd6d..5ef078c1 100644
--- a/Crow/src/IML/Node.cs
+++ b/Crow/src/IML/Node.cs
@@ -39,7 +39,7 @@ namespace Crow.IML
 		/// <returns>The child addition method</returns>
 		/// <param name="childIdx">child index or, template root node has index == -1</param>
 		public MethodInfo GetAddMethod(int childIdx){
-			if (typeof (Group).IsAssignableFrom (CrowType))
+			if (typeof (GroupBase).IsAssignableFrom (CrowType))
 				return CompilerServices.miAddChild;
 			if (typeof (Container).IsAssignableFrom (CrowType))
 				return CompilerServices.miSetChild;
diff --git a/Crow/src/ItemTemplate.cs b/Crow/src/ItemTemplate.cs
index e4fc2d8e..7e2f7194 100644
--- a/Crow/src/ItemTemplate.cs
+++ b/Crow/src/ItemTemplate.cs
@@ -279,8 +279,8 @@ namespace Crow
 		}
 		public static List<Widget> GetChildren (this Widget go) {
 			Type goType = go.GetType ();
-			if (typeof (Group).IsAssignableFrom (goType))
-				return (go as Group).Children;
+			if (typeof (GroupBase).IsAssignableFrom (goType))
+				return (go as GroupBase).Children;
 			if (typeof (Container).IsAssignableFrom (goType))
 				return new List<Widget> (new Widget[] { (go as Container).Child });
 			if (typeof (TemplatedContainer).IsAssignableFrom (goType))
diff --git a/Crow/src/Widgets/Group.cs b/Crow/src/Widgets/Group.cs
index d5e3d5e0..4ce70c4a 100644
--- a/Crow/src/Widgets/Group.cs
+++ b/Crow/src/Widgets/Group.cs
@@ -12,76 +12,20 @@ using static Crow.Logger;
 
 namespace Crow
 {
-	public class Group : Widget
+	public class Group : GroupBase
     {
-		#if DESIGN_MODE
-		public override bool FindByDesignID(string designID, out Widget go){
-			go = null;
-			if (base.FindByDesignID (designID, out go))
-				return true;
-			childrenRWLock.EnterReadLock ();
-			foreach (Widget w in Children) {
-				if (!w.FindByDesignID (designID, out go))
-					continue;
-				childrenRWLock.ExitReadLock ();
-				return true;
-			}
-			childrenRWLock.ExitReadLock ();
-			return false;
-		}
-		public override void getIML (System.Xml.XmlDocument doc, System.Xml.XmlNode parentElem)
-		{
-			if (this.design_isTGItem)
-				return;
-			base.getIML (doc, parentElem);
-			foreach (Widget g in Children) {
-				g.getIML (doc, parentElem.LastChild);	
-			}
-		}
-		#endif
-
-		protected ReaderWriterLockSlim childrenRWLock = new ReaderWriterLockSlim(LockRecursionPolicy.SupportsRecursion);
 
 		#region CTOR
 		public Group () {}
 		public Group(Interface iface, string style = null) : base (iface, style) { }
 		#endregion
 
+		internal Widget largestChild = null;
+		internal Widget tallestChild = null;
 		#region EVENT HANDLERS
 		public event EventHandler<EventArgs> ChildrenCleared;
 		#endregion
-
-		internal Widget largestChild = null;
-		internal Widget tallestChild = null;
-
-        bool _multiSelect = false;
-		ObservableList<Widget> children = new ObservableList<Widget>();
-
-        public virtual ObservableList<Widget> Children => children;
-		[DefaultValue(false)]
-        public bool MultiSelect
-        {
-            get => _multiSelect;
-            set { _multiSelect = value; }
-        }
-		public virtual void AddChild(Widget g){
-			if (disposed) {
-				DbgLogger.AddEvent (DbgEvtType.AlreadyDisposed | DbgEvtType.GOAddChild);
-				return;
-			}
-
-			childrenRWLock.EnterWriteLock();
-
-			g.Parent = this;
-			Children.Add (g);
-
-			childrenRWLock.ExitWriteLock();
-
-			//g.RegisteredLayoutings = LayoutingType.None;
-			g.LayoutChanged += OnChildLayoutChanges;
-			g.RegisterForLayouting (LayoutingType.Sizing | LayoutingType.ArrangeChildren);
-		}
-        public virtual void RemoveChild(Widget child)
+        public override void RemoveChild(Widget child)
 		{
 			child.LayoutChanged -= OnChildLayoutChanges;
 			//check if HoverWidget is removed from Tree
@@ -106,12 +50,7 @@ namespace Crow
 			this.RegisterForLayouting (LayoutingType.Sizing | LayoutingType.ArrangeChildren);
 
 		}
-        public virtual void DeleteChild(Widget child)
-		{
-			RemoveChild (child);
-			child.Dispose ();
-        }
-		public virtual void InsertChild (int idx, Widget g) {
+		public override void InsertChild (int idx, Widget g) {
 			if (disposed) {
 				DbgLogger.AddEvent (DbgEvtType.AlreadyDisposed | DbgEvtType.GOAddChild);
 				return;
@@ -120,20 +59,23 @@ namespace Crow
 				
 			g.Parent = this;
 			Children.Insert (idx, g);
-
+			
 			childrenRWLock.ExitWriteLock ();
 
-			g.RegisteredLayoutings = LayoutingType.None;
+			if (g.LastSlots.Width > contentSize.Width) {
+				largestChild = g;
+				contentSize.Width = g.LastSlots.Width;
+			}
+			if (g.LastSlots.Height > contentSize.Height) {
+				tallestChild = g;
+				contentSize.Height = g.LastSlots.Height;
+			}
+
+			
 			g.LayoutChanged += OnChildLayoutChanges;
 			g.RegisterForLayouting (LayoutingType.Sizing | LayoutingType.ArrangeChildren);
 		}
-		public virtual void RemoveChild (int idx) {
-			RemoveChild (children[idx]);
-		}
-		public virtual void DeleteChild (int idx) {
-			DeleteChild (children[idx]);
-		}
-		public virtual void ClearChildren()
+		public override void ClearChildren()
 		{
 			childrenRWLock.EnterWriteLock ();
 
@@ -151,104 +93,17 @@ namespace Crow
 			RegisterForLayouting (LayoutingType.Sizing);
 			ChildrenCleared.Raise (this, new EventArgs ());
 		}
-		public override void OnDataSourceChanged (object sender, DataSourceChangeEventArgs e)
-		{
-			base.OnDataSourceChanged (this, e);
-
-			childrenRWLock.EnterReadLock ();
-			foreach (Widget g in Children) {
-				if (g.localDataSourceIsNull & g.localLogicalParentIsNull)
-					g.OnDataSourceChanged (g, e);	
-			}
-			childrenRWLock.ExitReadLock ();
-		}
-
-		public void putWidgetOnTop(Widget w)
-		{
-			if (Children.Contains(w))
-			{
-				childrenRWLock.EnterWriteLock ();
-
-				Children.Remove (w);
-				Children.Add (w);
-
-				childrenRWLock.ExitWriteLock ();
-			}
-		}
-		public void putWidgetOnBottom(Widget w)
-		{
-			if (Children.Contains(w))
-			{
-				childrenRWLock.EnterWriteLock ();
-
-				Children.Remove (w);
-				Children.Insert (0, w);
-
-				childrenRWLock.ExitWriteLock ();
-			}
-		}
 
 		#region GraphicObject overrides
-
-		public override Widget FindByName (string nameToFind)
-		{
-			if (Name == nameToFind)
-				return this;
-			Widget tmp = null;
-
-			childrenRWLock.EnterReadLock ();
-
-			foreach (Widget w in Children) {
-				tmp = w.FindByName (nameToFind);
-				if (tmp != null)
-					break;
-			}
-
-			childrenRWLock.ExitReadLock ();
-
-			return tmp;
-		}
-		public override Widget FindByType<T> ()
-		{
-			if (this is T)
-				return this;
-			Widget tmp = null;
-
-			childrenRWLock.EnterReadLock ();
-
-			foreach (Widget w in Children) {
-				tmp = w.FindByType<T> ();
-				if (tmp != null)
-					break;
-			}
-
-			childrenRWLock.ExitReadLock ();
-
-			return tmp;
-		}
-		public override bool Contains (Widget goToFind)
-		{
-			foreach (Widget w in Children) {
-				if (w == goToFind)
-					return true;
-				if (w.Contains (goToFind))
-					return true;
-			}
-			return false;
-		}
 		public override int measureRawSize (LayoutingType lt)
 		{
 			if (Children.Count > 0) {
 				if (lt == LayoutingType.Width) {
 					if (largestChild == null)
-						searchLargestChild ();
-					if (largestChild == null)
-						searchLargestChild (true);
+						searchLargestChild ();					
 				} else {
 					if (tallestChild == null)
-						searchTallestChild ();
-					if (tallestChild == null)
-						searchTallestChild (true);
+						searchTallestChild ();					
 				}
 			}
 			return base.measureRawSize (lt);
@@ -262,97 +117,29 @@ namespace Crow
 			//position smaller objects in group when group size is fit
 			switch (layoutType) {
 			case LayoutingType.Width:
+				//childrenRWLock.EnterReadLock ();
 				foreach (Widget c in Children) {
 					if (c.Width.IsRelativeToParent)
 						c.RegisterForLayouting (LayoutingType.Width);
 					else
 						c.RegisterForLayouting (LayoutingType.X);
 				}
+				//childrenRWLock.ExitReadLock ();
 				break;
 			case LayoutingType.Height:
+				//childrenRWLock.EnterReadLock ();
 				foreach (Widget c in Children) {
 					if (c.Height.IsRelativeToParent)
 						c.RegisterForLayouting (LayoutingType.Height);
 					else
 						c.RegisterForLayouting (LayoutingType.Y);
 				}
+				//childrenRWLock.ExitReadLock ();
 				break;
 			}
 			childrenRWLock.ExitReadLock ();
 		}
-		protected override void onDraw (Context gr)
-		{
-			DbgLogger.StartEvent (DbgEvtType.GODraw, this);
-
-			base.onDraw (gr);			
-
-			if (ClipToClientRect) {
-				gr.Save ();
-				//clip to client zone
-				CairoHelpers.CairoRectangle (gr, ClientRectangle, CornerRadius);
-				gr.Clip ();
-			}
-
-			childrenRWLock.EnterReadLock ();
-
-			for (int i = 0; i < Children.Count; i++) 
-				Children[i].Paint (gr);			
-
-			childrenRWLock.ExitReadLock ();
-
-			if (ClipToClientRect)
-				gr.Restore ();
-
-			DbgLogger.EndEvent (DbgEvtType.GODraw);
-		}
-		protected override void UpdateCache (Context ctx)
-		{
-			DbgLogger.StartEvent(DbgEvtType.GOUpdateCache, this);
-			if (!Clipping.IsEmpty) {
-				using (Context gr = new Context (bmp)) {
-					for (int i = 0; i < Clipping.NumRectangles; i++)
-						gr.Rectangle(Clipping.GetRectangle(i));
-					gr.ClipPreserve();
-					gr.Operator = Operator.Clear;
-					gr.Fill();
-					gr.Operator = Operator.Over;
-
-					base.onDraw (gr);
-
-					if (ClipToClientRect) {
-						CairoHelpers.CairoRectangle (gr, ClientRectangle, CornerRadius);
-						gr.Clip ();
-					}
-
-					childrenRWLock.EnterReadLock ();
-
-					foreach (Widget c in Children) {
-						if (!c.IsVisible)
-							continue;
-						if (Clipping.Contains (c.Slot + ClientRectangle.Position) == RegionOverlap.Out)
-							continue;
-						c.Paint (gr);
-					}
-
-					childrenRWLock.ExitReadLock ();
-
-					#if DEBUG_CLIP_RECTANGLE
-					/*gr.LineWidth = 1;
-					gr.SetSourceColor(Color.DarkMagenta.AdjustAlpha (0.8));
-					for (int i = 0; i < Clipping.NumRectangles; i++)
-						gr.Rectangle(Clipping.GetRectangle(i));
-					gr.Stroke ();*/
-					#endif
-				}
-				DbgLogger.AddEvent (DbgEvtType.GOResetClip, this);
-				Clipping.Reset ();
-			}/*else
-				Console.WriteLine("GROUP REPAINT WITH EMPTY CLIPPING");*/
-			paintCache (ctx, Slot + Parent.ClientRectangle.Position);
-			DbgLogger.EndEvent(DbgEvtType.GOUpdateCache);				
-		}
 		#endregion
-
 		public virtual void OnChildLayoutChanges (object sender, LayoutingEventArgs arg)
 		{
 			DbgLogger.StartEvent(DbgEvtType.GOOnChildLayoutChange, this);
@@ -361,38 +148,28 @@ namespace Crow
 
 			switch (arg.LayoutType) {
 			case LayoutingType.Width:
-				if (Width != Measure.Fit) {
-					DbgLogger.EndEvent(DbgEvtType.GOOnChildLayoutChange);
-					return;
-				}
-				if (g.Slot.Width > contentSize.Width) {
-					largestChild = g;
-					contentSize.Width = g.Slot.Width;
-				} else if (g == largestChild)
-					searchLargestChild ();
-				else {
-					DbgLogger.EndEvent(DbgEvtType.GOOnChildLayoutChange);
-					return;
+				if (Width == Measure.Fit) {
+					if (g.Slot.Width > contentSize.Width) {
+						largestChild = g;
+						contentSize.Width = g.Slot.Width;
+					} else if (g == largestChild)
+						searchLargestChild ();
+					else
+						break;
+					this.RegisterForLayouting (LayoutingType.Width);
 				}
-
-				this.RegisterForLayouting (LayoutingType.Width);
 				break;
 			case LayoutingType.Height:
-				if (Height != Measure.Fit) {
-					DbgLogger.EndEvent(DbgEvtType.GOOnChildLayoutChange);					
-					return;
-				}
-				if (g.Slot.Height > contentSize.Height) {
-					tallestChild = g;
-					contentSize.Height = g.Slot.Height;
-				} else if (g == tallestChild)
-					searchTallestChild ();
-				else {
-					DbgLogger.EndEvent(DbgEvtType.GOOnChildLayoutChange);
-					return;
+				if (Height == Measure.Fit) {
+					if (g.Slot.Height > contentSize.Height) {
+						tallestChild = g;
+						contentSize.Height = g.Slot.Height;
+					} else if (g == tallestChild)
+						searchTallestChild ();
+					else
+						break;
+					this.RegisterForLayouting (LayoutingType.Height);
 				}
-
-				this.RegisterForLayouting (LayoutingType.Height);
 				break;
 			}
 			DbgLogger.EndEvent(DbgEvtType.GOOnChildLayoutChange);
@@ -403,10 +180,12 @@ namespace Crow
 			tallestChild = null;
 			contentSize = 0;
 		}
-		void searchLargestChild (bool forceMeasure = false)
+		protected virtual void searchLargestChild (bool forceMeasure = false)
 		{
 			DbgLogger.StartEvent (DbgEvtType.GOSearchLargestChild, this);
 
+			//childrenRWLock.EnterReadLock ();
+
 			largestChild = null;
 			contentSize.Width = 0;
 			for (int i = 0; i < Children.Count; i++) {
@@ -414,8 +193,8 @@ namespace Crow
 					continue;
 				int cw = 0;
 				if (forceMeasure)
-					cw = children [i].measureRawSize (LayoutingType.Width);
-				else if (children [i].RegisteredLayoutings.HasFlag (LayoutingType.Width))
+					cw = Children [i].measureRawSize (LayoutingType.Width);
+				else if (Children [i].RegisteredLayoutings.HasFlag (LayoutingType.Width))
 					continue;
 				else
 					cw = Children [i].Slot.Width;
@@ -424,13 +203,19 @@ namespace Crow
 					largestChild = Children [i];
 				}
 			}
+			if (largestChild == null && !forceMeasure)
+				searchLargestChild (true);
+
+			//childrenRWLock.ExitReadLock ();
 
 			DbgLogger.EndEvent (DbgEvtType.GOSearchLargestChild);
 		}
-		void searchTallestChild (bool forceMeasure = false)
+		protected virtual void searchTallestChild (bool forceMeasure = false)
 		{
 			DbgLogger.StartEvent (DbgEvtType.GOSearchTallestChild, this);
 
+			//childrenRWLock.EnterReadLock ();
+
 			tallestChild = null;
 			contentSize.Height = 0;
 			for (int i = 0; i < Children.Count; i++) {
@@ -438,8 +223,8 @@ namespace Crow
 					continue;
 				int ch = 0;
 				if (forceMeasure)
-					ch = children [i].measureRawSize (LayoutingType.Height);
-				else if (children [i].RegisteredLayoutings.HasFlag (LayoutingType.Height))
+					ch = Children [i].measureRawSize (LayoutingType.Height);
+				else if (Children [i].RegisteredLayoutings.HasFlag (LayoutingType.Height))
 					continue;
 				else
 					ch = Children [i].Slot.Height;
@@ -448,50 +233,12 @@ namespace Crow
 					tallestChild = Children [i];
 				}
 			}
+			if (tallestChild == null && !forceMeasure)
+				searchTallestChild (true);
 
-			DbgLogger.EndEvent (DbgEvtType.GOSearchTallestChild);
-		}
-
+			//childrenRWLock.ExitReadLock ();
 
-		#region Mouse handling
-		public override void checkHoverWidget (MouseMoveEventArgs e) {
-			base.checkHoverWidget (e);//TODO:check if not possible to put it at beginning of meth to avoid doubled check to DropTarget.
-			childrenRWLock.EnterReadLock ();
-			for (int i = Children.Count - 1; i >= 0; i--) {
-				if (Children[i].MouseIsIn (e.Position)) {
-					Children[i].checkHoverWidget (e);
-					childrenRWLock.ExitReadLock ();
-					return;
-				}
-			}
-			childrenRWLock.ExitReadLock ();			
-		}
-//		public override bool PointIsIn (ref Point m)
-//		{
-//			if (!base.PointIsIn (ref m))
-//				return false;
-//			if (CurrentInterface.HoverWidget == this)
-//				return true;
-//			lock (Children) {
-//				for (int i = Children.Count - 1; i >= 0; i--) {
-//					if (Children [i].Slot.ContainsOrIsEqual (m) && !(bool)CurrentInterface.HoverWidget?.IsOrIsInside(Children[i])) {						
-//						return false;
-//					}
-//				}
-//			}
-//			return true;
-//		}
-		#endregion
-
-		protected override void Dispose (bool disposing)
-		{
-			if (disposing) {
-				childrenRWLock.EnterReadLock ();
-				foreach (Widget c in children)
-					c.Dispose ();
-				childrenRWLock.ExitReadLock ();
-			}
-			base.Dispose (disposing);
+			DbgLogger.EndEvent (DbgEvtType.GOSearchTallestChild);
 		}
 	}
 }
diff --git a/Crow/src/Widgets/GroupBase.cs b/Crow/src/Widgets/GroupBase.cs
new file mode 100644
index 00000000..0ef24bda
--- /dev/null
+++ b/Crow/src/Widgets/GroupBase.cs
@@ -0,0 +1,302 @@
+// Copyright (c) 2013-2021  Jean-Philippe Bruyère <jp_bruyere@hotmail.com>
+//
+// This code is licensed under the MIT license (MIT) (http://opensource.org/licenses/MIT)
+
+using System;
+using System.Collections.Generic;
+using System.ComponentModel;
+using Crow.Cairo;
+using System.Threading;
+
+using static Crow.Logger;
+
+namespace Crow
+{
+	public abstract class GroupBase : Widget
+    {
+		#if DESIGN_MODE
+		public override bool FindByDesignID(string designID, out Widget go){
+			go = null;
+			if (base.FindByDesignID (designID, out go))
+				return true;
+			childrenRWLock.EnterReadLock ();
+			foreach (Widget w in Children) {
+				if (!w.FindByDesignID (designID, out go))
+					continue;
+				childrenRWLock.ExitReadLock ();
+				return true;
+			}
+			childrenRWLock.ExitReadLock ();
+			return false;
+		}
+		public override void getIML (System.Xml.XmlDocument doc, System.Xml.XmlNode parentElem)
+		{
+			if (this.design_isTGItem)
+				return;
+			base.getIML (doc, parentElem);
+			foreach (Widget g in Children) {
+				g.getIML (doc, parentElem.LastChild);	
+			}
+		}
+		#endif
+		protected ReaderWriterLockSlim childrenRWLock = new ReaderWriterLockSlim(LockRecursionPolicy.SupportsRecursion);
+
+		#region CTOR
+		public GroupBase () {}
+		public GroupBase (Interface iface, string style = null) : base (iface, style) { }
+		#endregion
+
+        bool _multiSelect = false;
+		ObservableList<Widget> children = new ObservableList<Widget>();
+        public virtual ObservableList<Widget> Children => children;
+
+		[DefaultValue(false)]
+        public bool MultiSelect
+        {
+            get => _multiSelect;
+            set {
+				if (_multiSelect == value)
+					return;
+				_multiSelect = value;
+				NotifyValueChangedAuto (_multiSelect);
+			}
+        }
+		public virtual void AddChild(Widget g){
+			InsertChild (children.Count, g);
+		}
+        public virtual void RemoveChild(Widget child)
+		{
+			//check if HoverWidget is removed from Tree
+			if (IFace.HoverWidget != null) {
+				if (this.Contains (IFace.HoverWidget))
+					IFace.HoverWidget = null;
+			}
+
+			childrenRWLock.EnterWriteLock ();
+
+			Children.Remove(child);
+			child.Parent = null;
+			child.LogicalParent = null;
+
+			childrenRWLock.ExitWriteLock ();
+		}
+        public virtual void DeleteChild(Widget child)
+		{
+			RemoveChild (child);
+			child.Dispose ();
+        }
+		public virtual void InsertChild (int idx, Widget g) {
+			if (disposed) {
+				DbgLogger.AddEvent (DbgEvtType.AlreadyDisposed | DbgEvtType.GOAddChild);
+				return;
+			}
+			childrenRWLock.EnterWriteLock ();
+				
+			g.Parent = this;
+			Children.Insert (idx, g);
+
+			childrenRWLock.ExitWriteLock ();			
+		}
+		public virtual void RemoveChild (int idx) {
+			RemoveChild (children[idx]);
+		}
+		public virtual void DeleteChild (int idx) {
+			DeleteChild (children[idx]);
+		}
+		public virtual void ClearChildren()
+		{
+			childrenRWLock.EnterWriteLock ();
+
+			while (Children.Count > 0) {
+				Widget g = Children [Children.Count - 1];
+				Children.RemoveAt (Children.Count - 1);
+				g.Dispose ();
+			}
+
+			childrenRWLock.ExitWriteLock ();
+		}
+		public override void OnDataSourceChanged (object sender, DataSourceChangeEventArgs e)
+		{
+			base.OnDataSourceChanged (this, e);
+
+			childrenRWLock.EnterReadLock ();
+			foreach (Widget g in Children) {
+				if (g.localDataSourceIsNull & g.localLogicalParentIsNull)
+					g.OnDataSourceChanged (g, e);	
+			}
+			childrenRWLock.ExitReadLock ();
+		}
+
+		public void putWidgetOnTop(Widget w)
+		{
+			if (Children.Contains(w))
+			{
+				childrenRWLock.EnterWriteLock ();
+
+				Children.Remove (w);
+				Children.Add (w);
+
+				childrenRWLock.ExitWriteLock ();
+			}
+		}
+		public void putWidgetOnBottom(Widget w)
+		{
+			if (Children.Contains(w))
+			{
+				childrenRWLock.EnterWriteLock ();
+
+				Children.Remove (w);
+				Children.Insert (0, w);
+
+				childrenRWLock.ExitWriteLock ();
+			}
+		}
+
+		#region GraphicObject overrides
+		public override Widget FindByName (string nameToFind)
+		{
+			if (Name == nameToFind)
+				return this;
+			Widget tmp = null;
+
+			childrenRWLock.EnterReadLock ();
+
+			foreach (Widget w in Children) {
+				tmp = w.FindByName (nameToFind);
+				if (tmp != null)
+					break;
+			}
+
+			childrenRWLock.ExitReadLock ();
+
+			return tmp;
+		}
+		public override Widget FindByType<T> ()
+		{
+			if (this is T)
+				return this;
+			Widget tmp = null;
+
+			childrenRWLock.EnterReadLock ();
+
+			foreach (Widget w in Children) {
+				tmp = w.FindByType<T> ();
+				if (tmp != null)
+					break;
+			}
+
+			childrenRWLock.ExitReadLock ();
+
+			return tmp;
+		}
+		public override bool Contains (Widget goToFind)
+		{
+			foreach (Widget w in Children) {
+				if (w == goToFind)
+					return true;
+				if (w.Contains (goToFind))
+					return true;
+			}
+			return false;
+		}
+
+		protected override void onDraw (Context gr)
+		{
+			DbgLogger.StartEvent (DbgEvtType.GODraw, this);
+
+			base.onDraw (gr);			
+
+			if (ClipToClientRect) {
+				gr.Save ();
+				//clip to client zone
+				CairoHelpers.CairoRectangle (gr, ClientRectangle, CornerRadius);
+				gr.Clip ();
+			}
+
+			childrenRWLock.EnterReadLock ();
+
+			for (int i = 0; i < Children.Count; i++) 
+				Children[i].Paint (gr);			
+
+			childrenRWLock.ExitReadLock ();
+
+			if (ClipToClientRect)
+				gr.Restore ();
+
+			DbgLogger.EndEvent (DbgEvtType.GODraw);
+		}
+		protected override void UpdateCache (Context ctx)
+		{
+			DbgLogger.StartEvent(DbgEvtType.GOUpdateCache, this);
+			if (!Clipping.IsEmpty) {
+				using (Context gr = new Context (bmp)) {
+					for (int i = 0; i < Clipping.NumRectangles; i++)
+						gr.Rectangle(Clipping.GetRectangle(i));
+					gr.ClipPreserve();
+					gr.Operator = Operator.Clear;
+					gr.Fill();
+					gr.Operator = Operator.Over;
+
+					base.onDraw (gr);
+
+					if (ClipToClientRect) {
+						CairoHelpers.CairoRectangle (gr, ClientRectangle, CornerRadius);
+						gr.Clip ();
+					}
+
+					childrenRWLock.EnterReadLock ();
+
+					foreach (Widget c in Children) {
+						if (!c.IsVisible)
+							continue;
+						if (Clipping.Contains (c.Slot + ClientRectangle.Position) == RegionOverlap.Out)
+							continue;
+						c.Paint (gr);
+					}
+
+					childrenRWLock.ExitReadLock ();
+
+					#if DEBUG_CLIP_RECTANGLE
+					/*gr.LineWidth = 1;
+					gr.SetSourceColor(Color.DarkMagenta.AdjustAlpha (0.8));
+					for (int i = 0; i < Clipping.NumRectangles; i++)
+						gr.Rectangle(Clipping.GetRectangle(i));
+					gr.Stroke ();*/
+					#endif
+				}
+				DbgLogger.AddEvent (DbgEvtType.GOResetClip, this);
+				Clipping.Reset ();
+			}/*else
+				Console.WriteLine("GROUP REPAINT WITH EMPTY CLIPPING");*/
+			paintCache (ctx, Slot + Parent.ClientRectangle.Position);
+			DbgLogger.EndEvent(DbgEvtType.GOUpdateCache);				
+		}
+		#endregion
+
+		#region Mouse handling
+		public override void checkHoverWidget (MouseMoveEventArgs e) {
+			base.checkHoverWidget (e);//TODO:check if not possible to put it at beginning of meth to avoid doubled check to DropTarget.
+			childrenRWLock.EnterReadLock ();
+			for (int i = Children.Count - 1; i >= 0; i--) {
+				if (Children[i].MouseIsIn (e.Position)) {
+					Children[i].checkHoverWidget (e);
+					childrenRWLock.ExitReadLock ();
+					return;
+				}
+			}
+			childrenRWLock.ExitReadLock ();			
+		}
+		#endregion
+
+		protected override void Dispose (bool disposing)
+		{
+			if (disposing) {
+				childrenRWLock.EnterReadLock ();
+				foreach (Widget c in Children)
+					c.Dispose ();
+				childrenRWLock.ExitReadLock ();
+			}
+			base.Dispose (disposing);
+		}
+	}
+}
diff --git a/Crow/src/Widgets/Table copy.cs b/Crow/src/Widgets/Table copy.cs
new file mode 100644
index 00000000..5aeaede8
--- /dev/null
+++ b/Crow/src/Widgets/Table copy.cs	
@@ -0,0 +1,259 @@
+// Copyright (c) 2019-2021  Jean-Philippe Bruyère <jp_bruyere@hotmail.com>
+//
+// This code is licensed under the MIT license (MIT) (http://opensource.org/licenses/MIT)
+using System;
+using System.ComponentModel;
+using System.Linq;
+using Crow.Cairo;
+
+namespace Crow
+{
+	/// <summary>
+	/// Table column definition
+	/// </summary>
+	public class Column2 : IValueChange
+	{
+		#region IValueChange implementation
+		public event EventHandler<ValueChangeEventArgs> ValueChanged;
+		public virtual void NotifyValueChanged (string MemberName, object _value)
+			=> ValueChanged.Raise (this, new ValueChangeEventArgs (MemberName, _value));
+		#endregion
+
+		string caption;
+		Measure width = Measure.Fit;
+		public int ComputedWidth;
+		public Widget LargestWidget;
+
+		public string Caption {
+			get => caption;
+			set {
+				if (caption == value)
+					return;
+				caption = value;
+				NotifyValueChanged ("Caption", caption);
+			}
+		}
+		/// <summary>
+		/// column width, special value 'Inherit' will be used to share table width equaly among columns
+		/// </summary>
+		/// <value>The column's width.</value>
+		public Measure Width {
+			get => width;
+			set {
+				if (width == value)
+					return;
+				width = value;
+				NotifyValueChanged ("Width", width);
+			}
+		}
+
+		public static Column Parse (string str) {
+			if (string.IsNullOrEmpty (str))
+				return null;				
+			Column c = new Column();
+			string[] tmp = str.Split (',');
+			c.Caption = tmp[0];
+			if (tmp.Length > 1)
+				c.Width = Measure.Parse (tmp[1]);
+			return c;
+		}
+	}
+
+
+	public class Table2 : VerticalStack
+	{
+		#region CTOR
+		public Table2 ()  {}
+		public Table2 (Interface iface, string style = null) : base (iface, style) { }
+		#endregion
+
+		//int lineWidth;
+		ObservableList<Column> columns = new ObservableList<Column>();
+
+		public ObservableList<Column> Columns {
+			get => columns;
+			set {
+				if (columns == value)
+					return;
+				if (columns != null) {
+					columns.ListAdd -= Ol_AddColumn;
+					columns.ListAdd -= Ol_RemoveColumn;
+
+					foreach (Column c in columns) 
+						c.ValueChanged += column_valueChanged;					
+				}
+
+				columns = value;
+
+				if (columns != null) {
+					columns.ListAdd += Ol_AddColumn;
+					columns.ListAdd += Ol_RemoveColumn;
+
+					foreach (Column c in columns) 
+						c.ValueChanged += column_valueChanged;					
+
+					foreach (TableRow row in Children) {
+						for (int i = 0; i < columns.Count && i < row.Children.Count; i++)
+							row.Children[i].Width = columns[i].Width;
+					}
+				}
+				NotifyValueChangedAuto(columns);
+			}
+		}
+
+		void column_valueChanged (object sender, ValueChangeEventArgs e) {
+			switch (e.MemberName) {
+			case "Width":
+				int columnIdx = columns.IndexOf (sender as Column);
+				foreach (TableRow row in Children.OfType<TableRow>().Where (r => r.Children.Count > columnIdx)) 
+					row.Children[columnIdx].Width = (Measure)e.NewValue;
+				break;							
+			}
+		}
+
+		public override void AddChild (Widget child) {
+			if (!(child is TableRow tr))			
+				throw new Exception ("Table widget accept only TableRow as child.");
+			base.AddChild (child);
+
+			tr.Children.ListAdd += Ol_tableRow_ChildAdd;
+			tr.Children.ListRemove += Ol_tableRow_ChildRemove;
+			tr.Children.ListClear += Ol_tableRow_ChildClear;
+
+			for (int i = 0; i < columns.Count && i < tr.Children.Count; i++)
+				tr.Children[i].Width = columns[i].Width;
+		}
+		public override void RemoveChild(Widget child)
+		{
+			base.RemoveChild(child);
+
+			TableRow tr = child as TableRow;
+			tr.Children.ListAdd -= Ol_tableRow_ChildAdd;
+			tr.Children.ListRemove -= Ol_tableRow_ChildRemove;
+			tr.Children.ListClear -= Ol_tableRow_ChildClear;
+		}
+		void Ol_tableRow_ChildAdd (object sender, ListChangedEventArg e)
+		{
+			Widget w = e.Element as Widget;
+			if (e.Index < Columns.Count)
+				w.Width = Columns[e.Index].Width;
+			w.LayoutChanged += onTableRow_ChildLayoutChanges;
+		}
+		void Ol_tableRow_ChildRemove (object sender, ListChangedEventArg e) {
+			Widget w = e.Element as Widget;
+			w.LayoutChanged -= onTableRow_ChildLayoutChanges;
+		}
+		void Ol_tableRow_ChildClear (object sender, ListClearEventArg e) {
+			foreach (Widget w in e.Elements)				
+				w.LayoutChanged -= onTableRow_ChildLayoutChanges;
+		}
+		void onTableRow_ChildLayoutChanges (object sender, LayoutingEventArgs arg) {
+			if (Columns == null)
+				return;
+			Widget g = sender as Widget;
+			TableRow tr = g.Parent as TableRow;
+			int cIdx = tr.Children.IndexOf (g);
+			//if (cIdx < Columns.Count && Columns.wi)
+		}
+		void Ol_AddColumn (object sender, ListChangedEventArg e) {
+			(e.Element as Column).ValueChanged += column_valueChanged;
+			foreach (TableRow row in Children) {
+				for (int i = e.Index; i < columns.Count && i < row.Children.Count; i++)
+					row.Children[i].Width = columns[i].Width;												
+			}
+			
+		}
+		void Ol_RemoveColumn (object sender, ListChangedEventArg e) {
+			(e.Element as Column).ValueChanged -= column_valueChanged;
+			foreach (TableRow row in Children) {
+				for (int i = e.Index; i < columns.Count && i < row.Children.Count; i++)
+					row.Children[i].Width = columns[i].Width;												
+			}			
+		}
+
+
+		public override void ChildrenLayoutingConstraints(ILayoutable layoutable, ref LayoutingType layoutType)
+		{
+			//trigger layouting for width only in the first row, the other will be set at the same horizontal position and width.
+			if (layoutable == Children[0])
+				layoutType &= (~LayoutingType.X);	
+			else
+				layoutType &= (~(LayoutingType.X|LayoutingType.Width));			
+		}
+
+		//overriden to prevent search for largest child, all the rows have the same total width.
+		public override void ComputeChildrenPositions () {
+			int d = 0;
+			childrenRWLock.EnterReadLock();
+			foreach (TableRow c in Children) {
+				if (!c.IsVisible)
+					continue;
+				c.Slot.Y = d;
+				d += c.Slot.Height + Spacing;
+			}
+			childrenRWLock.ExitReadLock();			
+			IsDirty = true;
+		}
+/*		public override bool UpdateLayout(LayoutingType layoutType)
+		{
+			RegisteredLayoutings &= (~layoutType);
+
+			if (layoutType == LayoutingType.Width) {
+				//propagate column.width to each row's children
+			}
+			return base.UpdateLayout(layoutType);
+		}*/
+	
+		/*public override void OnChildLayoutChanges (object sender, LayoutingEventArgs arg) {			
+			TableRow row = sender as TableRow;
+			TableRow firstRow = Children[0] as TableRow;
+
+			if (arg.LayoutType == LayoutingType.Width) {
+				if (row == firstRow) {
+					base.OnChildLayoutChanges (sender, arg);										
+					foreach (TableRow r in Children.Skip(1)) {						
+						r.contentSize = firstRow.contentSize;
+						setChildWidth (r, firstRow.Slot.Width);
+					}					
+				}
+			}
+
+			base.OnChildLayoutChanges (sender, arg);
+		}*/
+		/*protected override void onDraw (Context gr) {
+			DbgLogger.StartEvent (DbgEvtType.GODraw, this);
+
+			base.onDraw (gr);
+
+			if (Children.Count > 0) {
+
+				Rectangle cb = ClientRectangle;
+				TableRow fr = Children[0] as TableRow;
+
+				
+				gr.LineWidth = lineWidth;
+				Foreground.SetAsSource (IFace, gr, cb);				
+				CairoHelpers.CairoRectangle (gr, cb, CornerRadius, lineWidth);
+				double x = 0.5 + cb.Left + fr.Margin + 0.5 * fr.Spacing + fr.Children[0].Slot.Width;				
+				for (int i = 1; i < fr.Children.Count ; i++)
+				{
+					gr.MoveTo (x, cb.Y);
+					gr.LineTo (x, cb.Bottom);
+					x += fr.Spacing + fr.Children[i].Slot.Width ;
+				}
+
+				//horizontal lines
+				x = 0.5 + cb.Top + 0.5 * Spacing + Children[0].Slot.Height;
+				for (int i = 0; i < Children.Count - 1; i++)
+				{
+					gr.MoveTo (cb.Left, x);
+					gr.LineTo (cb.Right, x);
+					x += Spacing + Children[i].Slot.Height ;
+				}
+				gr.Stroke ();
+			}
+
+			DbgLogger.EndEvent (DbgEvtType.GODraw);
+		}*/		
+	}	
+}
diff --git a/Crow/src/Widgets/Table.cs b/Crow/src/Widgets/Table.cs
index 0beafb56..5ddd1af8 100644
--- a/Crow/src/Widgets/Table.cs
+++ b/Crow/src/Widgets/Table.cs
@@ -22,7 +22,7 @@ namespace Crow
 		string caption;
 		Measure width = Measure.Fit;
 		public int ComputedWidth;
-		public Widget LargestWidget;
+		public Widget LargestChild;
 
 		public string Caption {
 			get => caption;
@@ -66,111 +66,306 @@ namespace Crow
 		public Table ()  {}
 		public Table (Interface iface, string style = null) : base (iface, style) { }
 		#endregion
+		int columnSpacing, borderLineWidth, verticalLineWidth, horizontalLineWidth, rowsMargin;
+		ObservableList<Column> columns;
+		HorizontalStack HeaderRow;
+		string headerCellTemplate;
+		IML.Instantiator headerCellITor;
 
-		//int lineWidth;
-		ObservableList<Column> columns = new ObservableList<Column>();
+		[DefaultValue ("#Crow.DefaultTableHeaderCell.template")]
+		public string HeaderCellTemplate {
+			get => headerCellTemplate;
+			set {
+				if (headerCellTemplate == value)
+					return;
+				headerCellTemplate = value;
+				NotifyValueChangedAuto (headerCellTemplate);
 
+				headerCellITor = new IML.Instantiator (IFace, HeaderCellTemplate);
+				createHeaderRow();
+			}
+		}
+		public override void InsertChild (int idx, Widget g) {
+			g.Width = Measure.Stretched;
+			g.Margin = RowsMargin;
+			base.InsertChild (idx, g);			
+		}
+		[DefaultValue (2)]
+		public int ColumnSpacing {
+			get => columnSpacing;
+			set {
+				if (columnSpacing == value)
+					return;
+				columnSpacing = value;
+				NotifyValueChangedAuto (columnSpacing);
+				if (HeaderRow != null)
+					HeaderRow.Spacing = ColumnSpacing;
+				//RegisterForLayouting (LayoutingType.Sizing | LayoutingType.ArrangeChildren);
+			}
+		}
+		[DefaultValue (1)]
+		public int BorderLineWidth {
+			get => borderLineWidth;
+			set {
+				if (borderLineWidth == value)
+					return;
+				borderLineWidth = value;
+				NotifyValueChangedAuto (borderLineWidth);
+				RegisterForRedraw ();
+			}
+		}
+		[DefaultValue (1)]
+		public int HorizontalLineWidth {
+			get => horizontalLineWidth;
+			set {
+				if (horizontalLineWidth == value)
+					return;
+				horizontalLineWidth = value;
+				NotifyValueChangedAuto (horizontalLineWidth);
+				RegisterForRedraw ();
+			}
+		}
+		[DefaultValue (1)]
+		public int VerticalLineWidth {
+			get => verticalLineWidth;
+			set {
+				if (verticalLineWidth == value)
+					return;
+				verticalLineWidth = value;
+				NotifyValueChangedAuto (verticalLineWidth);
+				RegisterForRedraw ();
+			}
+		}
+		[DefaultValue (1)]
+		public int RowsMargin {
+			get => rowsMargin;
+			set {
+				if (rowsMargin == value)
+					return;
+				rowsMargin = value;
+				NotifyValueChangedAuto (rowsMargin);
+				childrenRWLock.EnterReadLock ();
+				foreach (Widget row in Children)
+					row.Margin = rowsMargin;
+				childrenRWLock.ExitReadLock ();
+			}
+		}		
+		//int lineWidth;		
 		public ObservableList<Column> Columns {
 			get => columns;
 			set {
 				if (columns == value)
 					return;
+				if (columns != null) {
+					deleteHeaderRow ();
+					columns.ListAdd -= Ol_AddColumn;
+					columns.ListAdd -= Ol_RemoveColumn;
+				}
+
 				columns = value;
+
+				if (columns != null) {
+					createHeaderRow ();					
+					columns.ListAdd += Ol_AddColumn;
+					columns.ListAdd += Ol_RemoveColumn;
+				}
 				NotifyValueChangedAuto(columns);
 			}
 		}
-		public override void AddChild (Widget child) {
-			TableRow tr = child as TableRow;
-			if (tr == null)
-				throw new Exception ("Table widget accept only TableRow as child.");
-			base.AddChild (child);
+		void deleteHeaderRow () {
+			if (HeaderRow == null)
+				return;
+			DeleteChild (HeaderRow);
+			HeaderRow = null;
 		}
-		/*public override void ChildrenLayoutingConstraints(ILayoutable layoutable, ref LayoutingType layoutType)
+		void createHeaderRow () {
+			deleteHeaderRow ();
+			if (Columns == null || headerCellITor == null)
+				return;
+			HeaderRow = new HorizontalStack(IFace, "TableHeaderRow") {Spacing = ColumnSpacing};
+			InsertChild (0, HeaderRow);			
+			foreach (Column c in Columns) {
+				Widget cell = headerCellITor.CreateInstance();
+				cell.LayoutChanged += onHeaderCell_LayoutChanges;
+				HeaderRow.AddChild (cell);
+				cell.DataSource = c;
+			}
+		}
+		
+		void Ol_AddColumn (object sender, ListChangedEventArg e) {
+			HeaderRow.InsertChild (e.Index, headerCellITor.CreateInstance());
+			HeaderRow.DataSource = e.Element;
+		}
+		void Ol_RemoveColumn (object sender, ListChangedEventArg e) {
+			Widget w = HeaderRow.Children[e.Index];
+			HeaderRow.RemoveChild (e.Index);
+			w.Dispose ();
+		}
+		void onHeaderCell_LayoutChanges (object sender, LayoutingEventArgs e) {
+			if (Columns == null)
+				return;
+			if (e.LayoutType == LayoutingType.Width) {
+				Widget g = sender as Widget;
+				int cIdx = HeaderRow.Children.IndexOf (g);
+				if (cIdx < Columns.Count &&  Columns[cIdx].Width.IsFit)
+					searchLargestChildInColumn (cIdx);				
+				childrenRWLock.EnterReadLock ();
+				for (int i = 1; i < Children.Count; i++) {
+					TableRow row = Children[i] as TableRow;
+					if (row.Children.Count <= cIdx)
+						continue;
+					setRowCellWidth (row.Children[cIdx], g.Slot.Width);
+				}
+				childrenRWLock.ExitReadLock ();
+
+				RegisterForRedraw ();
+			} else if (e.LayoutType == LayoutingType.X) {
+				Widget g = sender as Widget;
+				int cIdx = HeaderRow.Children.IndexOf (g);
+				childrenRWLock.EnterReadLock ();
+				for (int i = 1; i < Children.Count; i++) {
+					TableRow row = Children[i] as TableRow;
+					if (row.Children.Count <= cIdx)
+						continue;
+					row.Children[cIdx].Slot.X = g.Slot.X;
+					row.RegisterForRedraw();
+				}
+				childrenRWLock.ExitReadLock ();
+				RegisterForRedraw ();
+			}
+		}
+		protected void setRowCellWidth (Widget w, int newW) {
+			if (newW == w.Slot.Width)
+				return;
+			
+			w.Slot.Width = newW;
+			w.IsDirty = true;
+			w.OnLayoutChanges (LayoutingType.Width);
+			w.LastSlots.Width = w.Slot.Width;
+			w.RegisterForRedraw ();
+		}		
+
+		public override void ClearChildren()
 		{
-			//trigger layouting for width only in the first row, the other will be set at the same horizontal position and width.
-			if (layoutable == Children[0])
-				layoutType &= (~LayoutingType.X);	
-			else
-				layoutType &= (~(LayoutingType.X|LayoutingType.Width));			
-		}*/
-
-		//overriden to prevent search for largest child, all the rows as the same total width.
-		public override void ComputeChildrenPositions () {
-			int d = 0;
-			childrenRWLock.EnterReadLock();
-			foreach (Widget c in Children) {
-				if (!c.Visible)
+			base.ClearChildren();
+			createHeaderRow ();
+		}
+
+		void searchLargestChildInColumn (int cIdx)
+		{
+			DbgLogger.StartEvent (DbgEvtType.GOSearchLargestChild, this);
+
+			Column c = Columns[cIdx];
+
+			childrenRWLock.EnterReadLock ();
+
+			c.LargestChild = null;
+			int largestWidth = 0;	
+			for (int i = 1; i < Children.Count; i++) {
+				TableRow row = Children[i] as TableRow;
+				if (!row.IsVisible)
 					continue;
-				c.Slot.Y = d;
-				d += c.Slot.Height + Spacing;
+				int cw = row.Children [cIdx]. measureRawSize (LayoutingType.Width);
+				if (cw > largestWidth) {
+					largestWidth = cw;
+					c.LargestChild = row.Children [cIdx];
+				}
 			}
-			childrenRWLock.ExitReadLock();			
-			IsDirty = true;
+			childrenRWLock.ExitReadLock ();
+
+			if (HeaderRow.Children[cIdx].Slot.Width > largestWidth) {
+				c.LargestChild = HeaderRow.Children[cIdx];
+				return;
+			}
+			HeaderRow.Children[cIdx].Slot.Width = largestWidth;
+			//HeaderRow.adjustStretchedGo (LayoutingType.Width);
+
+			DbgLogger.EndEvent (DbgEvtType.GOSearchLargestChild);
 		}
-		public override bool UpdateLayout(LayoutingType layoutType)
+		int splitIndex = -1;		
+		const int minColumnSize = 10;		
+		public override void onMouseMove(object sender, MouseMoveEventArgs e)
 		{
-			RegisteredLayoutings &= (~layoutType);
-
-			if (layoutType == LayoutingType.Width) {
-				//propagate column.width to each row's children
-				foreach (TableRow row in Children) {
-					for (int i = 0; i < Columns.Count && i < row.Children.Count; i++) 
-						row.Children[i].Width = Columns[i].Width;
-				}				
-			}
-			return base.UpdateLayout(layoutType);
-		}
-	
-		/*public override void OnChildLayoutChanges (object sender, LayoutingEventArgs arg) {			
-			TableRow row = sender as TableRow;
-			TableRow firstRow = Children[0] as TableRow;
-
-			if (arg.LayoutType == LayoutingType.Width) {
-				if (row == firstRow) {
-					base.OnChildLayoutChanges (sender, arg);										
-					foreach (TableRow r in Children.Skip(1)) {						
-						r.contentSize = firstRow.contentSize;
-						setChildWidth (r, firstRow.Slot.Width);
-					}					
+			
+			if (ColumnSpacing > 0 && Columns.Count > 0) {
+				Point m = ScreenPointToLocal (e.Position);
+				if (IFace.IsDown (Glfw.MouseButton.Left) && splitIndex >= 0) {					
+					int splitPos = (int)(0.5 * ColumnSpacing + m.X);					
+					if (splitPos > HeaderRow.Children[splitIndex].Slot.Left + minColumnSize && splitPos < HeaderRow.Children[splitIndex+1].Slot.Right - minColumnSize) {
+						Columns[splitIndex+1].Width = HeaderRow.Children[splitIndex+1].Slot.Right - splitPos;
+						splitPos -= ColumnSpacing;
+						Columns[splitIndex].Width =  splitPos - HeaderRow.Children[splitIndex].Slot.Left;
+						HeaderRow.RegisterForLayouting (LayoutingType.ArrangeChildren);
+						e.Handled = true;
+					}
+					//Console.WriteLine ($"left:{HeaderRow.Children[splitIndex].Slot.Left} right:{HeaderRow.Children[splitIndex+1].Slot.Right} splitPos:{splitPos} m:{m}");				
+				} else {
+					splitIndex = -1;					
+					for (int i = 0; i < Columns.Count - 1; i++)
+					{
+						Rectangle r = HeaderRow.Children[i].Slot;
+						if (m.X >= r.Right) {
+							r = HeaderRow.Children[i+1].Slot;
+							if (m.X <= r.Left && Columns.Count - 1 > i ) {
+								IFace.MouseCursor = MouseCursor.sb_h_double_arrow;
+								splitIndex = i;
+								e.Handled = true;
+								break;
+							}
+						}
+					}
+					if (splitIndex < 0 && IFace.MouseCursor == MouseCursor.sb_h_double_arrow)
+						IFace.MouseCursor = MouseCursor.top_left_arrow;
 				}
 			}
+			base.onMouseMove(sender, e);
+		}		
 
-			base.OnChildLayoutChanges (sender, arg);
-		}*/
-		/*protected override void onDraw (Context gr) {
+
+		protected override void onDraw (Context gr) {
 			DbgLogger.StartEvent (DbgEvtType.GODraw, this);
 
 			base.onDraw (gr);
 
-			if (Children.Count > 0) {
+			if (Columns != null && columns.Count > 0 && HeaderRow != null) {
 
 				Rectangle cb = ClientRectangle;
-				TableRow fr = Children[0] as TableRow;
-
-				
-				gr.LineWidth = lineWidth;
-				Foreground.SetAsSource (IFace, gr, cb);				
-				CairoHelpers.CairoRectangle (gr, cb, CornerRadius, lineWidth);
-				double x = 0.5 + cb.Left + fr.Margin + 0.5 * fr.Spacing + fr.Children[0].Slot.Width;				
-				for (int i = 1; i < fr.Children.Count ; i++)
-				{
-					gr.MoveTo (x, cb.Y);
-					gr.LineTo (x, cb.Bottom);
-					x += fr.Spacing + fr.Children[i].Slot.Width ;
+							
+				Foreground.SetAsSource (IFace, gr, cb);
+				if (BorderLineWidth > 0) {
+					gr.LineWidth = BorderLineWidth;
+					CairoHelpers.CairoRectangle (gr, cb, CornerRadius, borderLineWidth);
+					gr.Stroke ();
+				}
+				double x = 0;
+				if (VerticalLineWidth > 0) {
+					gr.LineWidth = VerticalLineWidth;
+					x = cb.Left + HeaderRow.Margin + 0.5 * ColumnSpacing + HeaderRow.Children[0].Slot.Width;// - 0.5 * VerticalLineWidth;				
+					for (int i = 1; i < HeaderRow.Children.Count ; i++)
+					{
+						gr.MoveTo (x, cb.Y);
+						gr.LineTo (x, cb.Bottom);
+						x += columnSpacing + HeaderRow.Children[i].Slot.Width ;
+					}
+					gr.Stroke ();
 				}
 
-				//horizontal lines
-				x = 0.5 + cb.Top + 0.5 * Spacing + Children[0].Slot.Height;
-				for (int i = 0; i < Children.Count - 1; i++)
-				{
-					gr.MoveTo (cb.Left, x);
-					gr.LineTo (cb.Right, x);
-					x += Spacing + Children[i].Slot.Height ;
+				if (HorizontalLineWidth > 0) {
+					gr.LineWidth = HorizontalLineWidth;
+					x = cb.Top + 0.5 * Spacing + Children[0].Slot.Height;// - 0.5 * HorizontalLineWidth;
+					for (int i = 1; i < Children.Count; i++)
+					{
+						gr.MoveTo (cb.Left, x);
+						gr.LineTo (cb.Right, x);
+						x += Spacing + Children[i].Slot.Height ;
+					}
+					gr.Stroke ();
 				}
-				gr.Stroke ();
+				
 			}
 
 			DbgLogger.EndEvent (DbgEvtType.GODraw);
-		}*/		
-	}	
+		}			
+
+	}
 }
diff --git a/Crow/src/Widgets/TableRow copy.cs b/Crow/src/Widgets/TableRow copy.cs
new file mode 100644
index 00000000..2184d486
--- /dev/null
+++ b/Crow/src/Widgets/TableRow copy.cs	
@@ -0,0 +1,321 @@
+// Copyright (c) 2019-2021  Jean-Philippe Bruyère <jp_bruyere@hotmail.com>
+//
+// This code is licensed under the MIT license (MIT) (http://opensource.org/licenses/MIT)
+using System;
+using System.ComponentModel;
+using System.Linq;
+using Crow.Cairo;
+using Glfw;
+
+namespace Crow
+{
+	public class TableRow2 : Group, ISelectable {
+		#region ISelectable implementation
+		bool isSelected;
+		public event EventHandler Selected;
+		public event EventHandler Unselected;
+		[DefaultValue (false)]
+		public virtual bool IsSelected {
+			get { return isSelected; }
+			set {
+				if (isSelected == value)
+					return;
+				isSelected = value;
+
+				if (isSelected)
+					Selected.Raise (this, null);
+				else
+					Unselected.Raise (this, null);
+
+				NotifyValueChangedAuto (isSelected);
+			}
+		}
+		#endregion
+
+		public Table Table => Parent as Table;		
+
+		public override void ChildrenLayoutingConstraints(ILayoutable layoutable, ref LayoutingType layoutType)
+		{
+			//trigger layouting for width only in the first row, the other will be set at the same horizontal position and width.
+			if (Table == null) {
+				base.ChildrenLayoutingConstraints (layoutable, ref layoutType);
+				return;
+			}
+			if (this == Table.Children[0])
+				layoutType &= (~LayoutingType.X);	
+			else
+				layoutType &= (~(LayoutingType.X|LayoutingType.Width));			
+		}
+
+
+		public override void OnLayoutChanges(LayoutingType  layoutType)
+		{
+			switch (layoutType) {
+			case LayoutingType.Width:
+				RegisterForLayouting (LayoutingType.X);
+				break;
+			case LayoutingType.Height:
+				childrenRWLock.EnterReadLock ();
+				foreach (Widget c in Children.Where (cc => cc.Height.IsRelativeToParent))
+					c.RegisterForLayouting (LayoutingType.Height);				
+				childrenRWLock.ExitReadLock ();
+				break;
+			}
+			raiseLayoutChanged (layoutType);
+		}
+
+		//all the rows have equal size
+		protected override void searchLargestChild(bool forceMeasure = false) {}
+
+
+
+
+		/*public override void ComputeChildrenPositions () {
+			if (Children.Count == 0)
+				return;
+			int spacing = Table.Spacing;
+			ObservableList<Column> cols = Table.Columns;
+						
+			Widget first = Children[0];
+			TableRow firstRow = Table.Children[0] as TableRow;
+
+			if (firstRow == this) {
+				base.ComputeChildrenPositions();
+				return;
+			}			
+			childrenRWLock.EnterReadLock();			
+			
+			for (int i = 0; i < Children.Count && i < firstRow.Children.Count; i++)
+			{
+				Widget w = Children[i];
+
+					w.Slot.X = firstRow.Children[i].Slot.X;
+					setChildWidth (w, firstRow.Children[i].Slot.Width);				
+				
+			}
+
+			childrenRWLock.ExitReadLock();
+			IsDirty = true;
+		}*/
+
+
+
+
+
+		/*public override void ComputeChildrenPositions () {
+			if (Children.Count == 0)
+				return;
+			int spacing = Table.Spacing;
+			ObservableList<Column> cols = Table.Columns;
+						
+			Widget first = Children[0];
+			TableRow firstRow = Table.Children[0] as TableRow;
+
+			if (firstRow == this) {
+				base.ComputeChildrenPositions();
+				return;
+			}			
+			childrenRWLock.EnterReadLock();			
+			
+			for (int i = 0; i < Children.Count && i < firstRow.Children.Count; i++)
+			{
+				Widget w = Children[i];
+
+					w.Slot.X = firstRow.Children[i].Slot.X;
+					setChildWidth (w, firstRow.Children[i].Slot.Width);				
+				
+			}
+
+			childrenRWLock.ExitReadLock();
+			IsDirty = true;
+		}*/
+
+
+
+
+
+		/*public override void ComputeChildrenPositions () {
+			if (Children.Count == 0)
+				return;
+			int spacing = Table.Spacing;
+			ObservableList<Column> cols = Table.Columns;
+						
+			Widget first = Children[0];
+			TableRow firstRow = Table.Children[0] as TableRow;
+
+			if (firstRow == this) {
+				base.ComputeChildrenPositions();
+				return;
+			}			
+			childrenRWLock.EnterReadLock();			
+			
+			for (int i = 0; i < Children.Count && i < firstRow.Children.Count; i++)
+			{
+				Widget w = Children[i];
+
+					w.Slot.X = firstRow.Children[i].Slot.X;
+					setChildWidth (w, firstRow.Children[i].Slot.Width);				
+				
+			}
+
+			childrenRWLock.ExitReadLock();
+			IsDirty = true;
+		}*/
+
+
+
+
+
+		/*public override void ComputeChildrenPositions () {
+			if (Children.Count == 0)
+				return;
+			int spacing = Table.Spacing;
+			ObservableList<Column> cols = Table.Columns;
+						
+			Widget first = Children[0];
+			TableRow firstRow = Table.Children[0] as TableRow;
+
+			if (firstRow == this) {
+				base.ComputeChildrenPositions();
+				return;
+			}			
+			childrenRWLock.EnterReadLock();			
+			
+			for (int i = 0; i < Children.Count && i < firstRow.Children.Count; i++)
+			{
+				Widget w = Children[i];
+
+					w.Slot.X = firstRow.Children[i].Slot.X;
+					setChildWidth (w, firstRow.Children[i].Slot.Width);				
+				
+			}
+
+			childrenRWLock.ExitReadLock();
+			IsDirty = true;
+		}*/
+		
+		/*public override bool UpdateLayout(LayoutingType layoutType)
+		{
+			RegisteredLayoutings &= (~layoutType);
+
+			if (Table == null)
+				return false;
+			TableRow firstRow = Table.Children[0] as TableRow;
+			if (layoutType == LayoutingType.Width) {
+				if (firstRow.RegisteredLayoutings.HasFlag (LayoutingType.Width))
+					return false;
+				if (this != firstRow) {					
+					Slot.Width = firstRow.Slot.Width;
+					if (Slot.Width != LastSlots.Width) {
+						IsDirty = true;
+						OnLayoutChanges (layoutType);
+						LastSlots.Width = Slot.Width;
+					}
+					if (RegisteredLayoutings == LayoutingType.None && IsDirty)
+						IFace.EnqueueForRepaint (this);
+
+					return true;
+				}
+			}
+			
+			return base.UpdateLayout(layoutType);
+		}*/
+		/*public override int measureRawSize (LayoutingType lt) {
+			if (lt == LayoutingType.Width) {
+				if (Table == null)
+					return -1;
+				TableRow firstRow = Table.Children[0] as TableRow;				
+				if (this != firstRow) {
+					if (firstRow.RegisteredLayoutings.HasFlag (LayoutingType.Width))
+						return -1;
+					contentSize = firstRow.contentSize;
+					return firstRow.measureRawSize (lt);
+				}
+
+			}
+			return base.measureRawSize (lt);
+		}*/
+		/*public override void OnChildLayoutChanges (object sender, LayoutingEventArgs arg) {
+			if (arg.LayoutType == LayoutingType.Width) {
+				Widget w = sender as Widget;
+				TableRow firstRow = Table.Children[0] as TableRow;
+				int c = Children.IndexOf(w);				
+				if (c < Table.Columns.Count) {
+					Column col = Table.Columns[c];
+					if (col.Width.IsFit) {
+						if (col.LargestWidget == null || w.Slot.Width > col.ComputedWidth) {
+							col.ComputedWidth = w.Slot.Width;
+							col.LargestWidget = w;
+						} else if (w == col.LargestWidget)
+							Console.WriteLine ("must search for largest widget");
+					}else if (w == firstRow)
+						col.ComputedWidth = w.Slot.Width;
+
+				}
+				Console.WriteLine ($"ROW:{Table.Children.IndexOf(this)} COL:{c} {w.LastSlots.Width} -> {w.Slot.Width} ");
+			}
+			base.OnChildLayoutChanges (sender, arg);
+		}*/
+		/*public override void OnChildLayoutChanges (object sender, LayoutingEventArgs arg) {
+			Widget go = sender as Widget;
+			TableRow row = go.Parent as TableRow;
+			TableRow firstRow = Table.Children[0] as TableRow;
+
+			if (arg.LayoutType == LayoutingType.Width) {
+				if (row == firstRow) {
+					base.OnChildLayoutChanges (sender, arg);
+					int idx = Children.IndexOf (go);					
+					foreach (TableRow r in Table.Children.Skip(1)) {
+						if (idx < r.Children.Count)
+							r.setChildWidth (r.Children[idx], go.Slot.Width);
+						r.contentSize = firstRow.contentSize;
+					}					
+				} //else
+					this.RegisterForLayouting (LayoutingType.ArrangeChildren);
+				return;
+			}
+
+			base.OnChildLayoutChanges (sender, arg);
+		}*/
+		int splitIndex = -1;		
+		const int minColumnSize = 10;
+		int Spacing => Table.Spacing;
+		public override void onMouseMove(object sender, MouseMoveEventArgs e)
+		{			
+			if (Spacing > 0 && Table != null && Table.Children.Count > 0) {
+				Point m = ScreenPointToLocal (e.Position);
+				if (IFace.IsDown (Glfw.MouseButton.Left) && splitIndex >= 0) {
+					TableRow firstRow = Table.Children[0] as TableRow;
+					Rectangle cb = ClientRectangle;
+					int splitPos = (int)(0.5 * Spacing + m.X);					
+					if (splitPos > firstRow.Children[splitIndex].Slot.Left + minColumnSize && splitPos < firstRow.Children[splitIndex+1].Slot.Right - minColumnSize) {
+						Table.Columns[splitIndex+1].Width = firstRow.Children[splitIndex+1].Slot.Right - splitPos;
+						splitPos -= Spacing;
+						Table.Columns[splitIndex].Width = splitPos - firstRow.Children[splitIndex].Slot.Left;
+						Table.RegisterForLayouting (LayoutingType.Width);
+						e.Handled = true;
+					}
+					//Console.WriteLine ($"left:{firstRow.Children[splitIndex].Slot.Left} right:{firstRow.Children[splitIndex+1].Slot.Right} cb.X:{cb.X} splitPos:{splitPos} m:{m}");				
+				} else {
+					splitIndex = -1;					
+					for (int i = 0; i < Children.Count - 1; i++)
+					{
+						Rectangle r = Children[i].Slot;
+						if (m.X >= r.Right) {
+							r = Children[i+1].Slot;
+							if (m.X <= r.Left && Table.Columns.Count - 1 > i ) {
+								IFace.MouseCursor = MouseCursor.sb_h_double_arrow;
+								splitIndex = i;
+								e.Handled = true;
+								break;
+							}
+						}
+					}
+					if (splitIndex < 0 && IFace.MouseCursor == MouseCursor.sb_h_double_arrow)
+						IFace.MouseCursor = MouseCursor.top_left_arrow;
+				}
+			}
+			base.onMouseMove(sender, e);
+		}
+	}
+}
diff --git a/Crow/src/Widgets/TableRow.cs b/Crow/src/Widgets/TableRow.cs
index dbb07661..1ce02c15 100644
--- a/Crow/src/Widgets/TableRow.cs
+++ b/Crow/src/Widgets/TableRow.cs
@@ -9,13 +9,11 @@ using Glfw;
 
 namespace Crow
 {
-	public class TableRow : HorizontalStack, ISelectable {
+	public class TableRow : GroupBase, ISelectable {
 		#region ISelectable implementation
 		bool isSelected;
-
 		public event EventHandler Selected;
 		public event EventHandler Unselected;
-
 		[DefaultValue (false)]
 		public virtual bool IsSelected {
 			get { return isSelected; }
@@ -33,173 +31,157 @@ namespace Crow
 			}
 		}
 		#endregion
-
-		public Table Table => Parent as Table;		
-
-		/*public override void ChildrenLayoutingConstraints(ILayoutable layoutable, ref LayoutingType layoutType)
-		{
-			//trigger layouting for width only in the first row, the other will be set at the same horizontal position and width.
-			if (Table == null) {
-				base.ChildrenLayoutingConstraints (layoutable, ref layoutType);
+		#region EVENT HANDLERS
+		public event EventHandler<EventArgs> ChildrenCleared;
+		#endregion
+		public override void ChildrenLayoutingConstraints(ILayoutable layoutable, ref LayoutingType layoutType)
+			=> layoutType &= (~(LayoutingType.X|LayoutingType.Width));		
+
+		public Table Table => Parent as Table;
+		internal Widget tallestChild = null;
+		public override void InsertChild (int idx, Widget g) {
+			if (disposed) {
+				DbgLogger.AddEvent (DbgEvtType.AlreadyDisposed | DbgEvtType.GOAddChild);
 				return;
 			}
-			if (this == Table.Children[0])
-				layoutType &= (~LayoutingType.X);	
-			else
-				layoutType &= (~(LayoutingType.X|LayoutingType.Width));			
-		}*/
-
-		public override void ComputeChildrenPositions () {
-			if (Children.Count == 0)
-				return;
-			int spacing = Table.Spacing;
-			ObservableList<Column> cols = Table.Columns;
-						
-			Widget first = Children[0];
-			TableRow firstRow = Table.Children[0] as TableRow;
-
-			if (firstRow == this) {
-				base.ComputeChildrenPositions();
-				return;
-			}			
-			childrenRWLock.EnterReadLock();			
+			childrenRWLock.EnterWriteLock ();
+				
+			g.Parent = this;
+			Children.Insert (idx, g);
 			
-			for (int i = 0; i < Children.Count && i < firstRow.Children.Count; i++)
-			{
-				Widget w = Children[i];
-				/*if (i < cols.Count && cols[i].Width.IsFit && cols[i].LargestWidget != null) {
-					w.Slot.X
-				}else{*/
-					w.Slot.X = firstRow.Children[i].Slot.X;
-					setChildWidth (w, firstRow.Children[i].Slot.Width);				
-				//}
+			childrenRWLock.ExitWriteLock ();
+
+			if (g.LastSlots.Height > contentSize.Height) {
+				tallestChild = g;
+				contentSize.Height = g.LastSlots.Height;
 			}
 
-			childrenRWLock.ExitReadLock();
-			IsDirty = true;
+			
+			g.LayoutChanged += OnChildLayoutChanges;
+			g.RegisterForLayouting (LayoutingType.Sizing | LayoutingType.ArrangeChildren);
 		}
-		
-		public override bool UpdateLayout(LayoutingType layoutType)
+		public override void RemoveChild(Widget child)
 		{
-			RegisteredLayoutings &= (~layoutType);
-
-			if (Table == null)
-				return false;
-			TableRow firstRow = Table.Children[0] as TableRow;
-			if (layoutType == LayoutingType.Width) {
-				if (firstRow.RegisteredLayoutings.HasFlag (LayoutingType.Width))
-					return false;
-				if (this != firstRow) {					
-					Slot.Width = firstRow.Slot.Width;
-					if (Slot.Width != LastSlots.Width) {
-						IsDirty = true;
-						OnLayoutChanges (layoutType);
-						LastSlots.Width = Slot.Width;
-					}
-					if (RegisteredLayoutings == LayoutingType.None && IsDirty)
-						IFace.EnqueueForRepaint (this);
-
-					return true;
-				}
+			child.LayoutChanged -= OnChildLayoutChanges;
+			//check if HoverWidget is removed from Tree
+			if (IFace.HoverWidget != null) {
+				if (this.Contains (IFace.HoverWidget))
+					IFace.HoverWidget = null;
 			}
-			
-			return base.UpdateLayout(layoutType);
+
+			childrenRWLock.EnterWriteLock ();
+
+			Children.Remove(child);
+			child.Parent = null;
+			child.LogicalParent = null;
+
+			childrenRWLock.ExitWriteLock ();
+
+			if (child == tallestChild && Height == Measure.Fit)
+				searchTallestChild ();
+
+			this.RegisterForLayouting (LayoutingType.Sizing | LayoutingType.ArrangeChildren);
+
 		}
-		/*public override int measureRawSize (LayoutingType lt) {
-			if (lt == LayoutingType.Width) {
-				if (Table == null)
-					return -1;
-				TableRow firstRow = Table.Children[0] as TableRow;				
-				if (this != firstRow) {
-					if (firstRow.RegisteredLayoutings.HasFlag (LayoutingType.Width))
-						return -1;
-					contentSize = firstRow.contentSize;
-					return firstRow.measureRawSize (lt);
-				}
+		public override void ClearChildren()
+		{
+			childrenRWLock.EnterWriteLock ();
 
+			while (Children.Count > 0) {
+				Widget g = Children [Children.Count - 1];
+				g.LayoutChanged -= OnChildLayoutChanges;
+				Children.RemoveAt (Children.Count - 1);
+				g.Dispose ();
 			}
-			return base.measureRawSize (lt);
-		}*/
-		/*public override void OnChildLayoutChanges (object sender, LayoutingEventArgs arg) {
-			if (arg.LayoutType == LayoutingType.Width) {
-				Widget w = sender as Widget;
-				TableRow firstRow = Table.Children[0] as TableRow;
-				int c = Children.IndexOf(w);				
-				if (c < Table.Columns.Count) {
-					Column col = Table.Columns[c];
-					if (col.Width.IsFit) {
-						if (col.LargestWidget == null || w.Slot.Width > col.ComputedWidth) {
-							col.ComputedWidth = w.Slot.Width;
-							col.LargestWidget = w;
-						} else if (w == col.LargestWidget)
-							Console.WriteLine ("must search for largest widget");
-					}else if (w == firstRow)
-						col.ComputedWidth = w.Slot.Width;
 
+			childrenRWLock.ExitWriteLock ();
+
+			resetChildrenMaxSize ();
+
+			RegisterForLayouting (LayoutingType.Sizing);
+			ChildrenCleared.Raise (this, new EventArgs ());
+		}
+		public override int measureRawSize (LayoutingType lt)
+		{
+			if (lt == LayoutingType.Height && Children.Count > 0 && tallestChild == null)
+				searchTallestChild ();					
+			return base.measureRawSize (lt);
+		}		
+		public override void OnLayoutChanges (LayoutingType layoutType)
+		{
+			base.OnLayoutChanges (layoutType);
+
+			childrenRWLock.EnterReadLock ();
+			//position smaller objects in group when group size is fit
+			switch (layoutType) {
+			case LayoutingType.Height:
+				childrenRWLock.EnterReadLock ();
+				foreach (Widget c in Children) {
+					if (c.Height.IsRelativeToParent)
+						c.RegisterForLayouting (LayoutingType.Height);
+					else
+						c.RegisterForLayouting (LayoutingType.Y);
 				}
-				Console.WriteLine ($"ROW:{Table.Children.IndexOf(this)} COL:{c} {w.LastSlots.Width} -> {w.Slot.Width} ");
+				childrenRWLock.ExitReadLock ();
+				break;
 			}
-			base.OnChildLayoutChanges (sender, arg);
-		}*/
-		/*public override void OnChildLayoutChanges (object sender, LayoutingEventArgs arg) {
-			Widget go = sender as Widget;
-			TableRow row = go.Parent as TableRow;
-			TableRow firstRow = Table.Children[0] as TableRow;
-
-			if (arg.LayoutType == LayoutingType.Width) {
-				if (row == firstRow) {
-					base.OnChildLayoutChanges (sender, arg);
-					int idx = Children.IndexOf (go);					
-					foreach (TableRow r in Table.Children.Skip(1)) {
-						if (idx < r.Children.Count)
-							r.setChildWidth (r.Children[idx], go.Slot.Width);
-						r.contentSize = firstRow.contentSize;
-					}					
-				} //else
-					this.RegisterForLayouting (LayoutingType.ArrangeChildren);
-				return;
+			childrenRWLock.ExitReadLock ();
+		}		
+		public virtual void OnChildLayoutChanges (object sender, LayoutingEventArgs arg)
+		{
+			DbgLogger.StartEvent(DbgEvtType.GOOnChildLayoutChange, this);
+
+			Widget g = sender as Widget;
+
+			switch (arg.LayoutType) {
+			case LayoutingType.Height:
+				if (Height == Measure.Fit) {
+					if (g.Slot.Height > contentSize.Height) {
+						tallestChild = g;
+						contentSize.Height = g.Slot.Height;
+					} else if (g == tallestChild)
+						searchTallestChild ();
+					else
+						break;
+					this.RegisterForLayouting (LayoutingType.Height);
+				}
+				break;
 			}
-
-			base.OnChildLayoutChanges (sender, arg);
-		}*/
-		int splitIndex = -1;		
-		const int minColumnSize = 10;
-		public override void onMouseMove(object sender, MouseMoveEventArgs e)
-		{			
-			if (Spacing > 0 && Table != null && Table.Children.Count > 0) {
-				Point m = ScreenPointToLocal (e.Position);
-				if (IFace.IsDown (Glfw.MouseButton.Left) && splitIndex >= 0) {
-					TableRow firstRow = Table.Children[0] as TableRow;
-					Rectangle cb = ClientRectangle;
-					int splitPos = (int)(0.5 * Spacing + m.X);					
-					if (splitPos > firstRow.Children[splitIndex].Slot.Left + minColumnSize && splitPos < firstRow.Children[splitIndex+1].Slot.Right - minColumnSize) {
-						Table.Columns[splitIndex+1].Width = firstRow.Children[splitIndex+1].Slot.Right - splitPos;
-						splitPos -= Spacing;
-						Table.Columns[splitIndex].Width = splitPos - firstRow.Children[splitIndex].Slot.Left;
-						Table.RegisterForLayouting (LayoutingType.Width);
-						e.Handled = true;
-					}
-					//Console.WriteLine ($"left:{firstRow.Children[splitIndex].Slot.Left} right:{firstRow.Children[splitIndex+1].Slot.Right} cb.X:{cb.X} splitPos:{splitPos} m:{m}");				
-				} else {
-					splitIndex = -1;					
-					for (int i = 0; i < Children.Count - 1; i++)
-					{
-						Rectangle r = Children[i].Slot;
-						if (m.X >= r.Right) {
-							r = Children[i+1].Slot;
-							if (m.X <= r.Left && Table.Columns.Count - 1 > i ) {
-								IFace.MouseCursor = MouseCursor.sb_h_double_arrow;
-								splitIndex = i;
-								e.Handled = true;
-								break;
-							}
-						}
-					}
-					if (splitIndex < 0 && IFace.MouseCursor == MouseCursor.sb_h_double_arrow)
-						IFace.MouseCursor = MouseCursor.top_left_arrow;
+			DbgLogger.EndEvent(DbgEvtType.GOOnChildLayoutChange);
+		}
+		protected virtual void searchTallestChild (bool forceMeasure = false)
+		{
+			DbgLogger.StartEvent (DbgEvtType.GOSearchTallestChild, this);
+
+			childrenRWLock.EnterReadLock ();
+
+			tallestChild = null;
+			contentSize.Height = 0;
+			for (int i = 0; i < Children.Count; i++) {
+				if (!Children [i].IsVisible)
+					continue;
+				int ch = 0;
+				if (forceMeasure)
+					ch = Children [i].measureRawSize (LayoutingType.Height);
+				else if (Children [i].RegisteredLayoutings.HasFlag (LayoutingType.Height))
+					continue;
+				else
+					ch = Children [i].Slot.Height;
+				if (ch > contentSize.Height) {
+					contentSize.Height = ch;
+					tallestChild = Children [i];
 				}
 			}
-			base.onMouseMove(sender, e);
+			if (tallestChild == null && !forceMeasure)
+				searchTallestChild (true);
+
+			childrenRWLock.ExitReadLock ();
+
+			DbgLogger.EndEvent (DbgEvtType.GOSearchTallestChild);
+		}
+		void resetChildrenMaxSize(){
+			tallestChild = null;
+			contentSize = 0;
 		}
 	}
 }
diff --git a/Crow/src/Widgets/Widget.cs b/Crow/src/Widgets/Widget.cs
index 47ac67f5..9f3f4781 100644
--- a/Crow/src/Widgets/Widget.cs
+++ b/Crow/src/Widgets/Widget.cs
@@ -911,18 +911,18 @@ namespace Crow
 				if (value == isVisible)
 					return;
 
-				isVisible = value;
+				isVisible = value;				
 				
-				if (!isVisible)
+				/*if (!isVisible)
 					unshownPostActions ();
-				RegisterForLayouting (LayoutingType.Sizing);
-				
-				/*if (isVisible){										
+				RegisterForLayouting (LayoutingType.Sizing);*/
+
+				if (isVisible){										
 					IsDirty = true;
-					RegisterForLayouting(LayoutingType.Sizing);
 				} else {
 					unshownPostActions ();					
-				}*/
+				}
+				RegisterForLayouting(LayoutingType.Sizing);
 				
 
 				NotifyValueChangedAuto (isVisible);
@@ -1641,9 +1641,9 @@ namespace Crow
 			if (LayoutChanged != null)
 				LayoutChanged.Invoke (this, new LayoutingEventArgs (layoutType));
 		}
-		internal protected void raiseLayoutChanged(LayoutingEventArgs e){
+		internal protected void raiseLayoutChanged(LayoutingType layoutingType){
 			if (LayoutChanged != null)
-				LayoutChanged.Raise (this, e);
+				LayoutChanged.Raise (this, new LayoutingEventArgs(layoutingType));
 		}
 		/// <summary> Update layout component only one at a time, this is where the computation of alignement
 		/// and size take place.
@@ -1834,6 +1834,7 @@ namespace Crow
 			DbgLogger.EndEvent (DbgEvtType.GORecreateCache);
 		}
 		protected void paintCache(Context ctx, Rectangle rb) {
+			DbgLogger.StartEvent(DbgEvtType.GOPaintCache, this);	
 			if (clearBackground) {
 				ctx.Operator = Operator.Clear;
 				ctx.Rectangle (rb);
@@ -1843,10 +1844,12 @@ namespace Crow
 
 			ctx.SetSource (bmp, rb.X, rb.Y);
 			ctx.Paint ();
+			DbgLogger.EndEvent(DbgEvtType.GOPaintCache);	
 		}
 		protected virtual void UpdateCache(Context ctx){
 			DbgLogger.StartEvent(DbgEvtType.GOUpdateCache, this);			
 			paintCache (ctx, Slot + Parent.ClientRectangle.Position);
+			DbgLogger.AddEvent (DbgEvtType.GOResetClip, this);
 			Clipping.Reset ();			
 			DbgLogger.EndEvent (DbgEvtType.GOUpdateCache);
 		}
@@ -1854,8 +1857,8 @@ namespace Crow
 		/// of the widget </summary>
 		public virtual void Paint (Context ctx)
 		{
-			if (!IsVisible)
-				return;
+			/*if (!IsVisible)
+				return;*/
 
 			DbgLogger.StartEvent (DbgEvtType.GOPaint, this);
 
@@ -2146,19 +2149,19 @@ namespace Crow
 		/// Checks to handle when widget is removed from the visible graphic tree
 		/// </summary>
 		void unshownPostActions () {
-			//IsDirty = true;
+			IsDirty = true;			
 
 			/*if (parent is Widget p)
 				p.RegisterForGraphicUpdate();
 			else*/
-			/*try
+			try
 			{
 				parent?.RegisterClip (ContextCoordinates(LastPaintedSlot));
 			}
 			catch (System.Exception e)
 			{
 				Debug.WriteLine($"[ERR]:unshownPostActions:{e}");
-			}*/
+			}
 				
 
 			if (IFace.ActiveWidget != null) {
@@ -2199,7 +2202,7 @@ namespace Crow
 			}
 			LastSlots = default;
 			LastPaintedSlot = default;*/
-			
+			//Slot = LastSlots = default;			
 		}
 	}
 }
-- 
2.47.3