Get "end-editing" notice from simple NSTextField?

FROM : Johnny Lundy
DATE : Sun Apr 13 23:57:18 2008

This list has been a great thing for me. I got 2 of my 3 stumpers 
solved with the help of people here.

What's the most clean and elegant (MVC compliant) way to receive an 
end-editing notice from a plain vanilla NSTextField?

I want my user to be able to just type in a string, end editing (by 
Return or Tab or changing focus), and then type in the next string, 
etc. and if my code can somehow get called I can add each entry to the 
array in the model.

I'd prefer not to use the Add: method of the array controllers unless 
it's the only clean way to do it, and of course avoid interacting with 
the NSTextField itself from the model.