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iOS Enumerations and Optionals in Swift Introduction to Enumerations Enum Methods

Why am I getting an error?

I don't understand why I am getting the error "constant named doneButton must be assigned the result"

// Example of UIBarButtonItem instance
// let someButton = UIBarButtonItem(title: "A Title", style: .plain, target: nil, action: nil)

enum Button {
  case done(String)
  case edit(String)

  func toUIBarButtonItem() -> UIBarButtonItem {
    switch self {
    case .done(let str): return UIBarButtonItem(title: str, style: .done, target: nil, action: nil)
    case .edit(let str): return UIBarButtonItem(title: str, style: .plain, target: nil, action: nil)

let done = Button.done("Save")
let doneButton = done.toUIBarButtonItem()

2 Answers


Try changing your last constant name from doneButton to button.

It seems the error referencing doneButton is its own mistake. I had the same issue; the instructions of the challenge say to use button. Otherwise, if thats not the only issue I'm not experienced enough to see it yet.

good luck

Sayuri Katz
Sayuri Katz
6,148 Points

enum BarButton { case done(title: String) case edit(title: String)

func BarButtonItem () -> UIBarButtonItem {
  switch self {
    case .done(let done): return UIBarButtonItem(title: done, style: .plain, target: nil, action: nil)
    case .edit(let edit): return UIBarButtonItem(title: edit, style: .plain, target: nil, action: nil)


let done = BarButton.done(title: "Save")