Which swift screen handler approach is better for instantiating a utility class and then presenting a viewController?

Question

1^st approach:

let whatsNewHandler = WhatsNewHandler(buildNumber: buildNumber)
 whatsNewHandler.showWhatNewScreeen(completion: { whatsNewVC in

      self.present(whatsNewVC, animated: true, completion: nil)
 })

2^nd approach, which looks a bit functional:

WhatsNewHandler(buildNumber: buildNumber).showWhatNewScreeen(completion: { whatsNewVC in

      self.present(whatsNewVC, animated: true, completion: nil)               
})

While both allocate the same amount of memory. I like the functional approach, I just do something and that's really it. But the reason I'm asking is I haven't seen anyone write like this. I see things similar to it when you're using a singleton, but this isn't a singleton.

EDIT:

My WhatNewHandler class:

import Foundation
import UIKit



typealias WhatsNewCompletionHandler = (_ whatsNewViewController: WhatsNewViewController) -> ()

class WhatsNewHandler{

    let buildNumber : String
    lazy var route : Router = {
      return Router.whatsNew(buildNumber: self.buildNumber)
    }()

    init(buildNumber: String){
        self.buildNumber = buildNumber
    }

    func showWhatNewScreeen(completion: @escaping WhatsNewCompletionHandler){

        NetworkHandler.sharedInstance.request(route, success: { json,_  in

            guard let json = json else{
                writelog("what's new json was nil")
                return
            }
            if let releaseBuild = ReleaseBuild(json: json){
                let WhatsNewVC = WhatsNewViewController(releaseBuild: releaseBuild)
                WhatsNewVC.modalPresentationStyle = .overFullScreen

                // TEST ALPHA ON REAL DEVICE
                WhatsNewVC.view.backgroundColor = UIColor.black.withAlphaComponent(0.985)
                completion(WhatsNewVC)
            }
            }, failed: {_,_,_ in

        })
    }
}

As for my WhatsNewViewController, kindly assume it to be a Viewcontroller that shows a list of new features added to the app.

Answer 1

The only difference between the first and the second approach is whether the handler is assigned to a variable or not. None of them is more "functional" than the other. Therefore:

• If you need a reference to the handler (perhaps to cancel the request) then use the first approach.
• If you don't need that reference, choose whatever you feel more comfortable with, or what you find better readable.

Some more remarks:

• The method name showWhatNewScreeen is (apart from the typo) misleading. The method creates a view controller but does not present it. Something like createWhatsNewController might be more appropriate.
• According to the API Design Guidelines, variable names should be lowerCamelCase, that is violated at let WhatsNewVC = ....

• The right-hand side of

  whatsNewVC.view.backgroundColor = UIColor.black.withAlphaComponent(0.985)
  

  can be abbreviated to .black.withAlphaComponent(0.985), the type UIColor is then inferred from the context.