+2  A: 

You have two tree controllers. Each has its own knowledge of the selection. Try binding selectionIndexPaths from both of the tree controllers to a property of your document (you'll need to provide a way to get there through the view controller).

Peter Hosey  2009-09-07 07:12:21
Thanks for the suggestion, but I'm a little (n00bishly) confused. How is my document going to be able to tell the tree controllers about the current selection? As I understand it, selection only exists with the tree controller and the outline view.
Ellie P.  2009-09-08 02:57:32
You would add a property to your document to hold those index paths. Remember, you do not have only one tree controll*er*, you have two tree controll*ers*, each with its own idea of what's selected. That's why you need to provide both of them some common object to hold that information. Your document is the object I would appoint to that role.
Peter Hosey  2009-09-08 07:53:33
Peter--thanks, it ended up working in the end. I thought I misunderstood what you said and that's why it still wasn't working, but it was another bug (or three) that were to blame.
Ellie P.  2009-09-14 16:30:17

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