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iOS Intermediate Swift 2 Properties Computed Properties

Posted by Michael Jones
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Michael Jones
Python Development Techdegree Graduate 38,554 Points

Can someone help me with the Computed Properties challenge.

In the editor I've created an enum to manage text presentation in my app. The enum members represent the three different text options. Your task is to create a computed property, style, that returns the correct style specifier provided below. For example Text.Headline.style should return the string "UIFontTextStyleHeadline".

enum.swift 
let UIFontTextStyleHeadline = "UIFontTextStyleHeadline"
let UIFontTextStyleBody = "UIFontTextStyleBody"
let UIFontTextStyleFootnote = "UIFontTextStyleFootnote"

enum Text {
  case Headline
  case Body
  case Footnote
}

1 Answer

Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Hello Michael :

You can treat computer properties like functions. You can add switch statements into them as well. 

let UIFontTextStyleHeadline = "UIFontTextStyleHeadline"
let UIFontTextStyleBody = "UIFontTextStyleBody"
let UIFontTextStyleFootnote = "UIFontTextStyleFootnote"

enum Text {
    case Headline
    case Body
    case Footnote

    var style: String {
        switch self {
        case .Headline:
            return UIFontTextStyleHeadline
        case .Body:
            return UIFontTextStyleBody
        case.Footnote:
            return UIFontTextStyleFootnote
        }
    }
}

Hope this helps

Michael Jones
.a{fill-rule:evenodd;}techdegree seal-36
Michael Jones
Python Development Techdegree Graduate 38,554 Points

Thank you. This does help.

Michael Jones
.a{fill-rule:evenodd;}techdegree seal-36
Michael Jones
Python Development Techdegree Graduate 38,554 Points

A little confused to how this worked without any errors. Don't we need to have to use default when using a Switch statement??

Jhoan Arango
Jhoan Arango
14,575 Points
Jhoan Arango
Jhoan Arango
14,575 Points

Not when the switch is exhaustive .. In this case we went through all the possible values in the enum.

Joshua Hardy
Joshua Hardy
17,317 Points

.Headline .Body & .Footnote need to be lowercase. The program must have been updated.

Eddie Aguilar
Eddie Aguilar
2,393 Points

Is the above answer the only possible way to complete this challenge?? I did not even think about using a switch statement.