Connect to ViewController from AppDelegate (Swift)

Question

I have created a new OS X Cocoa Application using the standard Xcode Swift template (using StoryBoards).

I have implemented an IBAction in AppDelegate.swift to handle wh

Answer 1

In Swift 5 and accessing new windows array:

@IBAction func menuAction(sender: AnyObject) {
    let storyboard = UIStoryboard(name: "Main", bundle: nil)
    let controller = storyboard.instantiateInitialViewController()
    // The windows in the array are ordered from back to front by window level;
    // thus, the last window in the array is on top of all other app windows.
    // On app launch, UIApplication.shared.windows.count == 1 anyway.
    if let window = UIApplication.shared.windows.last {
        window.rootViewController = controller
    }
}