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Liam George
Liam George
12,004 Points

fatal error: unexpectedly found nil while unwrapping an Optional value (lldb)

In the line "let coloursDictionary = playlistDictionary["backgroundColour"] as [String: CGFloat]" is comes back saying "fatal error: unexpectedly found nil while unwrapping an Optional value" I don't know how to fix it.

import Foundation
import UIKit

struct Playlist {

    var title: String?
    var description: String?
    var icon: UIImage?
    var largeIcon: UIImage?
    var artists: [String] = []
    var backgroundColour: UIColor = UIColor.clearColor()

    init(index: Int) {
        let musicLibrary = MusicLibrary().library
        let playlistDictionary = musicLibrary[index]

        title = playlistDictionary["title"] as String!
        description = playlistDictionary["description"] as String!

        let iconName = playlistDictionary["icon"] as String!
        icon = UIImage (named: iconName)

        let largeIconName = playlistDictionary["largeIcon"] as String!
        largeIcon = UIImage(named: largeIconName)

        artists += playlistDictionary["artists"] as [String]

        let coloursDictionary = playlistDictionary["backgroundColour"] as [String: CGFloat]

        backgroundColour = rgbColourFromDictionary(coloursDictionary)

    func rgbColourFromDictionary(colourDictionary: [String: CGFloat]) -> UIColor {

        let red = colourDictionary["red"]!
        let green = colourDictionary["green"]!
        let blue = colourDictionary["blue"]!
        let alpha = colourDictionary["alpha"]!

        return UIColor(red: red/255.0, green: green/255.0, blue: blue/255.0, alpha: alpha)


1 Answer

Jared Watkins
Jared Watkins
10,756 Points

The problem is that the provided code for the MusicLibrary Struct uses the key "backgroundColor" spelled the American way as 'color. Changing the key to 'backgroundColor' should fix it for you (although I had to change the spelling of 'color' to 'colour' in the the master and detail view controllers to get your code to work for me).

let coloursDictionary = playlistDictionary["backgroundColor"] as [String: CGFloat]

Hope this fixes it for you.