VirtualizingTreeView is a Unity UI control that can be used to represent hierarchical data. VirtualzingTreeView implements drag & drop, databinding, selection operations and is highly customizable. There are also two base clases VirtualizingItemsControl and VirtualizingItemContainer which can be used to implement your own virtualizing items control.
Main advantage of VirtualizingTreeView over TreeView is support for large (1000+) collections of data items
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