[TOptional](API\Runtime\Core\IO\TOptional)< EItemDropZone > HandleCanAcceptDrop ( const [FDragDropEvent](API\Runtime\SlateCore\Input\FDragDropEvent) & DragDropEvent, EItemDropZone DropZone, [TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FIKRigTreeElement](API\Plugins\IKRigEditor\RigEditor\FIKRigTreeElement) > TargetItem )