Gives a black screen when starting view controller swift

Question

When I switch from one screen to another, I get a black screen, I can't figure out why

Controller:

class AddContactsController: UIViewController {
    
    // MARK: - Constants
    private enum Constants {
        static let textField = "nameTextCell"
        static let datePicker = "datePicker"
        static let pickerView = "pickerView"
        static let textViewNotes = "textViewNotes"
        static let alertOk = "OK"
        static let alertQuestion = "It seems you made a mistake"
        static let navigationTitle = "Create"
    }
    
    // MARK: - AddPresenter
    var presenter: AddListPresenter?
    
    func instantiate() -> UIViewController {
        let vc = AddContactsController()
        let presenter = AddListPresenter()
        vc.presenter = presenter
        return vc
    }

Presenter:

class AddListPresenter {
    
    weak var view: AddListController?
    private var contact: Contact
    
    init(contact: Contact? = nil) {
        self.contact = contact ?? .init(
            name: "",
            surname: "",
            middleName: "",
            phone: "",
            email: "",
            date: "",
            sex: "",
            notes: ""
        )
    }
    
    private var saveHieght: CGFloat = 0

How can this be avoided. I don't want to transfer presenter declarations to viewDidLoad

Answer 1

When you create a view controller by invoking it's initializer directly( e.g AddContactsController(), it's content view does not get created automatically like it would from a storyboad or a nibfile.

If you are creating you UI in code you need to show us your loadView() method. That's where you code to create your view hierarchy belongs.

Unless you have implemented loadView() you won't get any content view and will see a black screen exactly as you describe.

You also need to show the code that calls your instantiate() method and what you do with the view controller instance that's returned.