1 files changed, 12 insertions, 10 deletions
diff --git a/Software/Visual_Studio/Tango.DragAndDrop/DragAndDropService.cs b/Software/Visual_Studio/Tango.DragAndDrop/DragAndDropService.cs
index e814985e6..8bd5e7e0b 100644
--- a/Software/Visual_Studio/Tango.DragAndDrop/DragAndDropService.cs
+++ b/Software/Visual_Studio/Tango.DragAndDrop/DragAndDropService.cs
@@ -11,6 +11,7 @@ using System.Windows.Media;
 using System.Windows.Media.Animation;
 using System.Windows.Media.Imaging;
 using System.Windows.Threading;
+using Tango.Core;
 using Tango.Core.EventArguments;
 
 
@@ -23,8 +24,8 @@ namespace Tango.DragAndDrop
     /// <seealso cref="DropEventArgs" />
     public static class DragAndDropService
     {
-        private static List<FrameworkElement> _dragElements;
-        private static List<FrameworkElement> _dropElements;
+        private static WeakList<FrameworkElement> _dragElements;
+        private static WeakList<FrameworkElement> _dropElements;
         private static Point _mouseDownLocation;
         private static FrameworkElement _currentDragedElement;
         private static FrameworkElement _currentDropElement;
@@ -59,8 +60,8 @@ namespace Tango.DragAndDrop
         /// </summary>
         static DragAndDropService()
         {
-            _dragElements = new List<FrameworkElement>();
-            _dropElements = new List<FrameworkElement>();
+            _dragElements = new WeakList<FrameworkElement>();
+            _dropElements = new WeakList<FrameworkElement>();
             _dragTimer = new DispatcherTimer();
             _dragTimer.Interval = TimeSpan.FromMilliseconds(30);
             _dragTimer.Tick += DragTimer_Tick;
@@ -573,13 +574,14 @@ namespace Tango.DragAndDrop
 
                 element.RegisterForPreviewMouseOrTouchDown(Draggable_PreviewMouseDown);
                 element.RegisterForMouseOrTouchMove(Draggable_MouseMove);
-                element.PreviewMouseUp += Draggable_PreviewMouseUp;
+                //element.PreviewMouseUp += Draggable_PreviewMouseUp;
+                element.AddHandler(FrameworkElement.PreviewMouseUpEvent, new MouseButtonEventHandler(Draggable_PreviewMouseUp));
                 //element.IsManipulationEnabled = true;
 
                 //element.AddHandler(FrameworkElement.PreviewMouseDownEvent, (MouseButtonEventHandler)Draggable_PreviewMouseDown, true);
                 //element.AddHandler(FrameworkElement.MouseMoveEvent, (MouseEventHandler)Draggable_MouseMove, true);
                 //element.AddHandler(FrameworkElement.PreviewMouseUpEvent, (MouseButtonEventHandler)Draggable_PreviewMouseUp, true);
-                element.Unloaded += Draggable_Unloaded;
+                //element.Unloaded += Draggable_Unloaded;
             }
         }
 
@@ -592,7 +594,7 @@ namespace Tango.DragAndDrop
             if (!_dropElements.Contains(element))
             {
                 _dropElements.Add(element);
-                element.Unloaded += Droppable_Unloaded;
+                //element.Unloaded += Droppable_Unloaded;
             }
         }
 
@@ -646,7 +648,7 @@ namespace Tango.DragAndDrop
         {
             if (_currentDragedElement != null)
             {
-                BitmapSource source =  _currentDragedElement.TakeSnapshot();
+                BitmapSource source = _currentDragedElement.TakeSnapshot();
                 _dragBorder = new Border();
 
                 var surface = GetDraggingSurface(_currentDragedElement);
@@ -761,7 +763,7 @@ namespace Tango.DragAndDrop
 
             FrameworkElement element = sender as FrameworkElement;
 
-            if (!_dragElements.Exists(x => x == element))
+            if (!_dragElements.ToList().Exists(x => x == element))
             {
                 e.Handled = false;
                 return;
@@ -772,7 +774,7 @@ namespace Tango.DragAndDrop
             _isMouseDown = true;
         }
 
-     
+
 
         /// <summary>
         /// Handles the MouseMove event of the Draggable control.