How to Create a UIViewController programmatically with view from storyboard

Question

I have a view controller designed in Main.storyboard named ProfileViewController also a corresponding class by that name. I can instantiate the viewController like this,

UIStoryboard(name: "SignUp", bundle: nil).instantiateViewController(withIdentifier: "ProfileViewController") as? ProfileViewController

However what I'd like to do is instantiate the view controller like this

let profileViewController = ProfileViewController(/*argument list*/)

Answer 1

Storyboard's view controllers MUST instantiate from storyboard . if you need a custom constructor function (like a initializer), you can define a simple one like this:

extension ProfileViewController {
    static func new(argument: any) -> ProfileViewController {
        let vc = UIStoryboard(name: "SignUp", bundle: nil).instantiateViewController(withIdentifier: "ProfileViewController") as! ProfileViewController
        vc.argument = argument
        return vc
    }
}

Note that if you want to use a real initializer, you can't use storyboard. You may use the view of the designed view controller and assign it to the view in initializer but you will loose other view controller settings.

extension ProfileViewController {
    convenience init(argument: Any) {
        self.init()
        self.view = UIStoryboard(name: "SignUp", bundle: nil).instantiateViewController(withIdentifier: "ProfileViewController").view
        self.argument = argument
    }
}