UI Controls fixes

Author: sergiye

Aga.Controls/Tree/AutoRowHeightLayout.cs

@@ -8,8 +8,8 @@ namespace Aga.Controls.Tree
 	public class AutoRowHeightLayout: IRowLayout
 	{
 		private DrawContext _measureContext;
-		private TreeViewAdv _treeView;
-		private List<Rectangle> _rowCache;
+		private readonly TreeViewAdv _treeView;
+		private readonly List<Rectangle> _rowCache;
 
 		public AutoRowHeightLayout(TreeViewAdv treeView, int rowHeight)
 		{
@@ -20,13 +20,7 @@ public AutoRowHeightLayout(TreeViewAdv treeView, int rowHeight)
 			_measureContext.Graphics = Graphics.FromImage(new Bitmap(1, 1));
 		}
 
-		private int _rowHeight;
-		public int PreferredRowHeight
-		{
-			get { return _rowHeight; }
-			set { _rowHeight = value; }
-		}
-
+		public int PreferredRowHeight { get; set; }
 
 		public int PageRowCount
 		{
@@ -117,6 +111,8 @@ private int GetRowHeight(int rowNo)
 		public int GetRowAt(Point point)
 		{
 			int py = point.Y - _treeView.ColumnHeaderHeight;
+			if (py < 0)  // Header column
+				return -1; 
 			int y = 0;
 			for (int i = _treeView.FirstVisibleRow; i < _treeView.RowCount; i++)
 			{

Aga.Controls/Tree/TreeViewAdv.Draw.cs

@@ -29,6 +29,10 @@ public void AutoSizeColumn(TreeColumn column)
 						if (nc.ParentColumn == column)
 							w += nc.GetActualSize(node, _measureContext).Width;
 					}
+					if (column.Index == 0)
+					{
+						w += node.Level * _indent + LeftMargin;
+					}
 					res = Math.Max(res, w);
 				}
 			}

Aga.Controls/Tree/TreeViewAdv.Input.cs

@@ -1,6 +1,4 @@
 using System;
-using System.Collections.Generic;
-using System.Text;
 using System.Windows.Forms;
 using System.Drawing;
 using Aga.Controls.Tree.NodeControls;
@@ -453,6 +451,8 @@ private void DragTimerTick(object state)
 		private void DragAutoScroll()
 		{
 			_dragAutoScrollFlag = false;
+			if (_vScrollBar.Minimum == _vScrollBar.Maximum)
+				return;
 			Point pt = PointToClient(MousePosition);
 			if (pt.Y < 20 && _vScrollBar.Value > 0)
 				_vScrollBar.Value--;