Please send me some links on how to use NSOutlineView with NSTreeController bindings without using core data.
In addition to the documentation, Apple's sample SourceView project should help you better understand things:
"SourceView" is a Cocoa application that demonstrates how to use NSOutlineView driven by NSTreeController and various other Cocoa classes to produce a Finder-like left column source view. Among the key features used to imitate this commonly used view are the use of NSTableViewSelectionHighlightStyleSourceList, NSViewController, NSCollectionView, and WebView.