Google: "NSArrayController class reference"
Find: selectedObjects:
The NSArrayController
instance methods are what you're going to want to use to query the selection. The binding guarantees that the array controller is in a state that matches whatever you have bound it to, usually a view. But the whole point of binding it, is so that you can use NSArrayController
methods to access that state.
This answer seems flippant -- let me google that for you -- but you're new, and especially with OSX APIs, you'll be referring to developer.apple.com class references all the time. AppKiDo and Dash are great tools to do that with.
You will also find isKindOfClass
useful.