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iOS Build a Playlist Browser with Swift Building the Music Library and Playlist Models Using a Playlist Instance

I get an error "EXC_BAD INSTRUCTION" when defining colorsDictionary constant for background color.

import Foundation import UIKit

struct Playlist {

var title: String?
var description: String?
var icon: UIImage?
var largeIcon:UIImage?
var artists: [String] = []
var backgroundColor: 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 colorsDictionary = playlistDictionary["backgroundcolor"] as! [String: CGFloat]
    backgroundColor = rgbFromDictionary(colorsDictionary)

func rgbFromDictionary(colorDictionary: [String: CGFloat]) -> UIColor {

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

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


1 Answer

Steven Deutsch
Steven Deutsch
21,046 Points

Hey Catherine Cho,

I think your colorDictionary constant is being set to nil because you are passing in an invalid key for the dictionary.

// Change "backgroundcolor" to backgroundColor"
let colorsDictionary = playlistDictionary["backgroundColor"] as! [String: CGFloat]

I hope this helps. Let me know if this solves your problem. Good Luck!

Ah that was a good catch. That fixed it. Thank you