DragDrop - How to detect element under cursor? (Droptarget)

Hey,

when I drag and drop a VisualElement onto another, how can I get a reference to the drop target? This is the manipulator (from uDamians youtube video) that's attached to my dragged item:

Spoiler

Code (CSharp):

1.     class ItemDragger : MouseManipulator
2.     {
3.         private Vector2 startPosition;
4.         private bool isDragging = false;
5.  
6.         public ItemDragger()
7.         {
8.             activators.Add(new ManipulatorActivationFilter { button = MouseButton.LeftMouse });
9.         }
10.         protected override void RegisterCallbacksOnTarget()
11.         {
12.             target.RegisterCallback<MouseDownEvent>(OnMouseDown);
13.             target.RegisterCallback<MouseMoveEvent>(OnMouseMove);
14.             target.RegisterCallback<MouseUpEvent>(OnMouseUp);
15.         }
16.         protected override void UnregisterCallbacksFromTarget()
17.         {
18.             target.UnregisterCallback<MouseDownEvent>(OnMouseDown);
19.             target.UnregisterCallback<MouseMoveEvent>(OnMouseMove);
20.             target.UnregisterCallback<MouseUpEvent>(OnMouseUp);
21.         }
22.         private void OnMouseDown(MouseDownEvent e)
23.         {
24.             if(isDragging)
25.             {
26.                 e.StopImmediatePropagation();
27.                 return;
28.             }
29.             if (CanStartManipulation(e))
30.             {
31.                 startPosition = e.localMousePosition;
32.                 isDragging = true;
33.                 target.CaptureMouse();
34.                 e.StopPropagation();
35.             }
36.         }
37.         private void OnMouseMove(MouseMoveEvent e)
38.         {
39.             if (!isDragging || !target.HasMouseCapture())
40.                 return;
41.  
42.             Vector2 diff = e.localMousePosition - startPosition;
43.  
44.             target.style.positionTop = target.layout.y + diff.y;
45.             target.style.positionLeft = target.layout.x + diff.x;
46.  
47.             e.StopPropagation();
48.         }
49.         private void OnMouseUp(MouseUpEvent e)
50.         {
51.             if (!isDragging || !target.HasMouseCapture() || !CanStopManipulation(e))
52.                 return;
53.             isDragging = false;
54.             target.ReleaseMouse();
55.             e.StopPropagation();
56.         }
57.     }

I've found classes like DragPerformEvent and DragUpdatedEvent, but I'm not sure on how to use them.

 

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