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iOS Enumerations and Optionals in Swift Introduction to Enumerations Enum Methods

I can't figure out where to go from here

In the editor you've been provided with a file buttons.swift that defines a BarButton type. Let's start simple. Declare a constant named done and assign an enum value of type BarButton with the member done. This member takes an associated value; assign it the string "Save". Next, add a method to the enum named button that returns an instance of the class UIBarButtonItem configured properly. An example of how to create an instance for this task is shown in the comments below. Use the same initializer. In the method, using the associated values as titles for the button, return a button with style UIBarButtonStyle.done for the done member of the BarButton enum. Similarly for the edit member, return a UIBarButtonItem instance with the style set to UIBarButtonStyle.plain. In both cases you can pass nil for target and action. Once you have a method, call it on the value we created in the previous task

buttons.swift
enum Button {
  case Done(String)
  case Edit(String)

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

case .Edit("Edit"): return UIBarButtonItem(title: "Edit", style: UIBarButtonStyle.Plain, target: nil, action: nil)
    }
  }
}

let doneButton = Button.Done

2 Answers

This should work:

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

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

    func button() -> 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")
let button = done.button()
codyl
codyl
4,692 Points

Did I miss a video? I don't see how you guys knew anything about "UIBarButtonItem"? How did you know to do that?