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iOS Swift 2.0 Enumerations and Optionals Introduction to Enumerations Enum Methods

Jeff Godown
Jeff Godown
1,714 Points

Don't understand how this wouldn't be exhaustive. What would be the default clause here then?

Am I even on the right track here? Thought this would be exhaustive because I have a case here for both types of Buttons. What would be the default clause, and why wouldn't this be exhaustive? Thanks!

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() -> 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 done = Button.Done("Done")

2 Answers

What is the default state that you want the button to be in before a user interacts with it? You can use that as your default case and comply to the Switch.

Jeremy Stewart
Jeremy Stewart
1,545 Points

Yah, I second that question. The enum has 2 cases, which both are being called in the function so isn't default unnecessary?