Intercepting NSSearchfield (Mac OSLib) selection?

I’m currently fiddling around with Mac OS Lib’s NSSearchfield class and find it in general very easy to use.

I have the user input a search string into it to update a list of possible matches, updated live, delayed by a revocable timer. This works great.

I have a menu item added to the list of recent searches and can process it when the user selects it. Great as well.

Not satisfying: I cannot find a way to call a method when the user selects a recent search which is then displayed immediately in the NSSearchfield. None of the edit events is triggered, and menu action event is only triggered when one of my own menu additions is called, not by selecting a recent search. I played a bit with the Lib definitions, but I’m obviously not experienced enough with all that declaration stuff.
Do you have any ideas?

Ok, answer from myself (and sorry for posting this into the wrong category initially):
I found that the action event gets fired – a bit too often, I thought there would be an event only being called when a selection via popup is being made –, but that’s better than nothing.
Just for curiosity: Would it be possible to extend the events to have a popup selection event?
(I must admit that the event definitions are a bit unclear for me still.)