I\'m trying to develop a NSPopUpButton that will serve as a filter to some datasource, let\'s say a NSArrayController that fills a table.
I
sounds to me like you're looking for the NSContentPlacementTagBindingOption.
you edit the NSMenu that's attached to the NSPopupButton as follows

you then edit the settings on the NSMenuItem you want to have replaced with your array controller contents so that it has a meaningful tag associated with it

you then specify that tag as the content placement tag value on the NSPopupButton's bindings for the content/content* bindings.
