void wnd_WindowDraged(object sender, EventArgs e)
        {
            //Helperを表示するBayがあるかどうかを調べる
            var mvForm = (DockFloatingWindow)sender;
            var hoverBay = _baysOrder.Concat(new[] { this }).Where(bay =>
                {
                    var mp = Mouse.GetPosition(bay);
                    return bay != mvForm.DockBay &&
                        (mp.X >= 0 && mp.X < bay.RenderSize.Width && mp.Y >= 0 && mp.Y < bay.RenderSize.Height);
                }).FirstOrDefault();
            _dragingBay = mvForm.DockBay;
            _hoverBay = hoverBay;

            //Helperを表示する必要がある場合は表示とマウスが乗ってる座標下の
            //Paneも探す。無い場合は非表示にし、各一時保存用変数をクリアする
            if (hoverBay != null)
            {
                var mPos = Mouse.GetPosition(hoverBay);
                var childAtPoint = hoverBay.GetChildAtPoint(mPos);
                _dragEffect = DockingHelper.GetDragDropEffect(hoverBay, childAtPoint);
                _hoverPane = childAtPoint;
                DockingHelper.ActiveIndicator = _dragEffect;
            }
            else
            {
                DockingHelper.Visibility = System.Windows.Visibility.Hidden;
                _dragEffect = DragDropEffects.None;
                _hoverPane = null;
                DockingHelper.ActiveIndicator = _dragEffect;
            }
            OnFloatingWindowMoved(new FloatFormEventArgs((DockFloatingWindow)sender));
        }
        void wnd_EndWindowDrag(object sender, EventArgs e)
        {
            if (_dragingBay == null)
                return;

            var len = _dragingBay.Items.Count == 1 && ((DockPaneBase)_dragingBay.Items[0]).Items.Count == 0
                ? ((DockPaneBase)_dragingBay.Items[0]).Length : new DockLength();
            switch (_dragEffect)
            {
                case DragDropEffects.Top:
                    _hoverPane.AddPanesOf(_dragingBay, DockDirection.Top, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.Bottom:
                    _hoverPane.AddPanesOf(_dragingBay, DockDirection.Bottom, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.Left:
                    _hoverPane.AddPanesOf(_dragingBay, DockDirection.Left, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.Right:
                    _hoverPane.AddPanesOf(_dragingBay, DockDirection.Right, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.Fill:
                    break;
                case DragDropEffects.OuterTop:
                    _hoverBay.AddPanesOf(_dragingBay, DockDirection.Top, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.OuterBottom:
                    _hoverBay.AddPanesOf(_dragingBay, DockDirection.Bottom, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.OuterLeft:
                    _hoverBay.AddPanesOf(_dragingBay, DockDirection.Left, len);
                    Window.GetWindow(this).Activate();
                    break;
                case DragDropEffects.OuterRight:
                    _hoverBay.AddPanesOf(_dragingBay, DockDirection.Right, len);
                    Window.GetWindow(this).Activate();
                    break;
                default:
                    break;
            }

            DockingHelper.Visibility = System.Windows.Visibility.Hidden;
            _hoverPane = null;
            _hoverBay = null;
            _dragingBay = null;
            _dragEffect = DragDropEffects.None;

            OnFloatingWindowEndMove(new FloatFormEventArgs((DockFloatingWindow)sender));
        }