Load SecondViewController automatically using Segue

Question

How to load SecondViewController simultaneously with ViewController inside viewDidLoad() method?

Segue's type is Sheet.

import Cocoa

class ViewController: NSViewController {

    override func viewDidLoad() {
        super.viewDidLoad()
        self.performSegue(withIdentifier: "secondVC", sender: self)
    }

    func prepareforSegue(segue: NSStoryboardSegue, sender: Any?) {
        if let identifier = segue.identifier, identifier == "secondVC" {
            _ = segue.destinationController as? SecondViewController
        }
    }
}

Answer 1

This

self.performSegue(withIdentifier: "secondVC", sender: self)

won't work inside viewDidLoad consider wraping it inside a Dispatch-after or inside a bool flag in viewDidAppear

DispatchQueue.main.asyncAfter(deadline:.now() + 2 ) {
   self.performSegue(withIdentifier: "secondVC", sender: self)
}

OR

var once = true
override func viewDidAppear() {
   super.viewDidAppear()
   if once {
        self.performSegue(withIdentifier: "secondVC", sender: self)
        once = false
   }
}