Get selected item in an NSMenu in Swift

I'm using the AMPathPopUpButton to save a text file, but the problem is that I can not get the folder selected by the user. The code looks like this:

import Cocoa;
class SaveFile: NSViewController {

    @IBOutlet weak var lista: NSMenu!

    override func viewDidLoad() {
        super.viewDidLoad();
    }

    override var representedObject: AnyObject? {
        didSet {

        }
    }

    @IBAction func save(sender: AnyObject) {

        //pegar valor aqui

    }
}