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

Thread 1: signal SIGABRT error?

When I try to run my app, I get an error message, highlighting a strand of code in green. I've double checked all of my code so far and can't find the error. Any ideas?

The line highlighted in green is:

class AppDelegate: UIResponder, UIApplicationDelegate (in the AppDelegate.swift)

It also produces output (at the bottom of XCode) that says:

2015-07-23 10:09:30.913 Algorhythm[2466:661850] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<Algorhythm.PlaylistMasterViewController 0x7fbc185b2960> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key playlistimageView0.' *** First throw call stack: (

2 Answers

Andreas Schürch
Andreas Schürch
2,087 Points

Had the same SIGABRT-Error. For me helped to

  1. delete the @IBOutlet in PlaylistMasterViewController.swift
  2. remove the Referencing Outlet (right-click on Image-View)
  3. and connect again the Image-View with ctrl + move with PlaylistMasterViewController.swift.
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Look at the left side of your code in the gutter, there is probably a fat, blue arrow on the line you get the error. Right click on it and select 'Delete Breakpoint'. Hope this helps!

Still not working. Here is the output error message:

Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<Algorhythm.PlaylistMasterViewController 0x7fb0abc17f90> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key playlistimageView0.'

And here is my PlaylistMasterViewController

import UIKit

class PlaylistMasterViewController: UIViewController {

    @IBOutlet weak var aButton: UIButton!

    @IBOutlet weak var playlistimageview0: UIImageView!

    override func viewDidLoad() {

        aButton.setTitle("Press me!", forState: .Normal)

        let playlist = Playlist(index: 0)
        playlistimageview0.image = playlist.icon 

    override func didReceiveMemoryWarning() {
        // Dispose of any resources that can be recreated.

    override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?){
        if segue.identifier == "showPlaylistDetail"{
           let playlistDetailController = segue.destinationViewController as!
            playlistDetailController.segueLabelText = "Yay! You pressed the button!"