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iOS Swift 2.0 Enumerations and Optionals Introduction to Enumerations Enum Methods

Ivan Belmonte
Ivan Belmonte
2,073 Points

Impossible exercise, nil selector won't compile

Hello folks, the exercise asks to pass nil as the "action" parameter but then the code won't compile. Maybe it's because i'm using swift 3. I changed the "action" property in the UIBarButtonItem to be optional so a nil value will pass. It works in my playground, but not in your web editor... again I'm afraid it's because of the swift version.

Best, Ivan

import Foundation

enum UIBarButtonStyle {
    case Done
    case Plain
    case Bordered

class UIBarButtonItem {

    var title: String?
    let style: UIBarButtonStyle
    var target: AnyObject?
    var action: Selector?

    init(title: String?, style: UIBarButtonStyle, target: AnyObject?, action: Selector?) {
        self.title = title
        self.style = style
        self.target = target
        self.action = action
enum Button {
    case Done(String)
    case Edit(String)

    func toUIBarButtonItem(title: String) -> UIBarButtonItem {
        switch self {
        case .Done: return UIBarButtonItem(title: title, style: UIBarButtonStyle.Done, target: nil, action: nil)
        case .Edit: return UIBarButtonItem(title: title, style: UIBarButtonStyle.Plain, target: nil, action: nil)

let doneButton = Button.Done("DoneButton")

1 Answer

Ivan Belmonte
Ivan Belmonte
2,073 Points

I solved it. Not giving the answer here but I was actually missing something.