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Carson Carbery
9,876 PointsCannot subscript a value of type '[NSDictionary]' with an index of type 'String'
Hi all,
I get the error above when trying to define the init method in this lesson. The error occurs each time I try and assign a value from the PlayListDictionary. For example the two lines below give the error for each line:
title = playListDictionary["title"] as String! description = playListDictionary["description"] as String!
I have checked the type and see that indeed playListDictionary is indeed an NSDictionary (but isn't that an objective C dictionary, so what is it doing here). I've double checked the code and it is exactly the same as that used by the teacher Pasan in this lesson.
Please help as I can not continue with the lesson without fixing this.
Many thanks
2 Answers
Tobias Helmrich
31,603 PointsHey Carson,
this course uses an older version of Swift but since Swift 1.2 you have to use the as! operator when you want to force downcast to a type instead of writing an exclamation mark after the type you want to downcast to.
So if you change this
title = playListDictionary["title"] as String!
description = playListDictionary["description"] as String!
to this
title = playListDictionary["title"] as! String
description = playListDictionary["description"] as! String
it should work. If it doesn't or if you have further questions please let me know. I hope that helps! :)
Carson Carbery
9,876 PointsSure here it is, thanks so much for checking through it:
// // Playlist.swift // Algorhythm
import Foundation import UIKit
struct Playlist { var title: String? var description: String? var icon: UIImage? var largeIcon: UIImage? var artist: [String] = [] var backGroundColor: UIColor = UIColor.clearColor()
init(index: Int){
let musicLibrary = MusicLibrary().library
let playListDictionary = musicLibrary
title = playListDictionary["title"] as! String
description = playListDictionary["description"] as! String
}
}
Tobias Helmrich
31,603 PointsSure, no problem! :) Make sure to specify the index of musicLibrary with the index you pass to the init method when you assign it to playListDictionary .
Like so:
let playListDictionary = musicLibrary[index]
I hope that fixes the problem, if not let me know!
Carson Carbery
9,876 PointsHi Tobias, I have just noticed that I missed adding in the index value on the musicLibrary, when I add that your answer above with the as! now seems to be working. Thanks very much for the help, I can progress now.
Tobias Helmrich
31,603 PointsNo problem, I'm glad you got it working! :)
Carson Carbery
9,876 PointsCarson Carbery
9,876 PointsHi Tobias,
I've made the change you suggested, so....
title = playListDictionary["title"] as! String
description = playListDictionary["description"] as! String
However I am getting exactly the same error :-/
Tobias Helmrich
31,603 PointsTobias Helmrich
31,603 PointsCould you please post the whole code for your
Playlist.swiftfile? :)