public override DragAndDropVisualMode DoDrag(TreeViewItem parentItem, TreeViewItem targetItem, bool perform, DropPosition dropPos)
{
var hierarchyTargetItem = targetItem as GameObjectTreeViewItem;
// Allow client to handle drag
if (m_CustomDragHandling != null)
{
DragAndDropVisualMode dragResult = m_CustomDragHandling(parentItem as GameObjectTreeViewItem, hierarchyTargetItem, dropPos, perform);
if (dragResult != DragAndDropVisualMode.None)
{
return(dragResult);
}
}
// Scene dragging logic
DragAndDropVisualMode dragSceneResult = DoDragScenes(parentItem as GameObjectTreeViewItem, hierarchyTargetItem, perform, dropPos);
if (dragSceneResult != DragAndDropVisualMode.None)
{
return(dragSceneResult);
}
if (targetItem != null && !IsDropTargetUserModifiable(hierarchyTargetItem, dropPos))
{
return(DragAndDropVisualMode.Rejected);
}
var option = HierarchyDropFlags.None;
var searchActive = !string.IsNullOrEmpty(dataSource.searchString);
if (searchActive)
{
option |= HierarchyDropFlags.SearchActive;
}
if (parentItem == null || targetItem == null)
{
// Here we are dragging outside any treeview items:
if (parentForDraggedObjectsOutsideItems != null)
{
// Use specific parent for DragAndDropForwarding
return(DragAndDrop.DropOnHierarchyWindow(0, option, parentForDraggedObjectsOutsideItems, perform));
}
else
{
// Simulate drag upon the last loaded scene in the hierarchy (adds as last root sibling of the last scene)
Scene lastScene = dataSource.GetLastScene();
if (!lastScene.IsValid())
{
return(DragAndDropVisualMode.Rejected);
}
option |= HierarchyDropFlags.DropUpon;
return(DragAndDrop.DropOnHierarchyWindow(lastScene.handle, option, null, perform));
}
}
// Here we are hovering over items
var draggingUpon = dropPos == TreeViewDragging.DropPosition.Upon;
if (searchActive && !draggingUpon)
{
return(DragAndDropVisualMode.None);
}
if (draggingUpon)
{
option |= HierarchyDropFlags.DropUpon;
}
else
{
if (dropPos == TreeViewDragging.DropPosition.Above)
{
option |= HierarchyDropFlags.DropAbove;
}
option |= HierarchyDropFlags.DropBetween;
}
bool isDroppingBetweenParentAndFirstChild = parentItem != null && targetItem != parentItem && dropPos == DropPosition.Above && parentItem.children[0] == targetItem;
if (isDroppingBetweenParentAndFirstChild)
{
option |= HierarchyDropFlags.DropAfterParent;
}
int gameObjectOrSceneInstanceID = GetDropTargetInstanceID(hierarchyTargetItem, dropPos);
if (gameObjectOrSceneInstanceID == 0)
{
return(DragAndDropVisualMode.Rejected);
}
if (perform && SubSceneGUI.IsUsingSubScenes() && !IsValidSubSceneDropTarget(gameObjectOrSceneInstanceID, dropPos, DragAndDrop.objectReferences))
{
return(DragAndDropVisualMode.Rejected);
}
return(DragAndDrop.DropOnHierarchyWindow(gameObjectOrSceneInstanceID, option, null, perform));
}