How to attach a custom menu to the main view in a OS X desktop app in Swift - swift

Question

Given the following GitHub project:
https://github.com/kellyjanderson/swift-custom-menue
How do I link the menu item Custom >> Custom Action, to the function customAction in the ViewController?

Answer 1

Define an outlet of your menu item in AppDelegate
#IBOutlet weak var customMenuItem: NSMenuItem!
In your view controller first get the instance of AppDelegate:
let appDelegate = NSApplication.sharedApplication().delegate as! AppDelegate
Get the instance of the menu item and then bind an IBAction to it:
appDelegate.customMenuItem.action = #selector(customAction(_:))
For e.g., you want to bind an action customAction to your menu item. You can add the following code in viewDidLoad
override func viewDidLoad() {
super.viewDidLoad()
let appDelegate = NSApplication.sharedApplication().delegate as! AppDelegate
print(appDelegate.customMenuItem)
appDelegate.customMenuItem.action = #selector(customAction(_:))
}
And then define the IBAction
func customAction(sender: NSMenuItem){
print("Custom Menu Item clicked")
}
Output:
<NSMenuItem: 0x6080000a0720 Custom Action>
Custom Menu Item clicked

Answer 2

So the linked question Why can't I connect my menu to my view controller IBAction? came close but did not provide a concrete solution for me. Here is how I solved this.
First in the ViewController you need to mark your function as an #IBAction
#IBAction func customAction(sender: NSMenuItem){
print("Custom Menu Item clicked")
}
Once that function is marked as an IBAction it will be available in the responder chain; so now you can control-click and drag the menu item to the first responder icon and select your function, in this example customAction.