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boris said
3,607 PointsError in app delegate.swift
So when I run my app it crashes and there is an error in app delegate.swift. This has happened to all my other apps I have tried to make recently. Here is the error code:
2016-03-01 06:15:01.986 Algorhythm[48318:4052082] Unknown class PlayMasterViewController in Interface Builder file. 2016-03-01 06:15:01.999 Algorhythm[48318:4052082] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<UIViewController 0x7fba20510540> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key aButton.' *** First throw call stack: ( 0 CoreFoundation 0x000000010376ee65 exceptionPreprocess + 165 1 libobjc.A.dylib 0x00000001054aedeb objc_exception_throw + 48 2 CoreFoundation 0x000000010376eaa9 -[NSException raise] + 9 3 Foundation 0x0000000103b379bb -[NSObject(NSKeyValueCoding) setValue:forKey:] + 288 4 UIKit 0x000000010411a320 -[UIViewController setValue:forKey:] + 88 5 UIKit 0x0000000104348f41 -[UIRuntimeOutletConnection connect] + 109 6 CoreFoundation 0x00000001036af4a0 -[NSArray makeObjectsPerformSelector:] + 224 7 UIKit 0x0000000104347924 -[UINib instantiateWithOwner:options:] + 1864 8 UIKit 0x0000000104120eea -[UIViewController _loadViewFromNibNamed:bundle:] + 381 9 UIKit 0x0000000104121816 -[UIViewController loadView] + 178 10 UIKit 0x0000000104121b74 -[UIViewController loadViewIfRequired] + 138 11 UIKit 0x00000001041222e7 -[UIViewController view] + 27 12 UIKit 0x0000000103ff8ab0 -[UIWindow addRootViewControllerViewIfPossible] + 61 13 UIKit 0x0000000103ff9199 -[UIWindow _setHidden:forced:] + 282 14 UIKit 0x000000010400ac2e -[UIWindow makeKeyAndVisible] + 42 15 UIKit 0x0000000103f83663 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 4131 16 UIKit 0x0000000103f89cc6 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1760 17 UIKit 0x0000000103f86e7b -[UIApplication workspaceDidEndTransaction:] + 188 18 FrontBoardServices 0x0000000107343754 -[FBSSerialQueue _performNext] + 192 19 FrontBoardServices 0x0000000107343ac2 -[FBSSerialQueue _performNextFromRunLoopSource] + 45 20 CoreFoundation 0x000000010369aa31 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 17 21 CoreFoundation 0x000000010369095c __CFRunLoopDoSources0 + 556 22 CoreFoundation 0x000000010368fe13 __CFRunLoopRun + 867 23 CoreFoundation 0x000000010368f828 CFRunLoopRunSpecific + 488 24 UIKit 0x0000000103f867cd -[UIApplication _run] + 402 25 UIKit 0x0000000103f8b610 UIApplicationMain + 171 26 Algorhythm 0x000000010358f45d main + 109 27 libdyld.dylib 0x0000000105fb792d start + 1 ) libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)
4 Answers
boris said
3,607 Pointsimport UIKit
class PlaylistMasterViewController: UIViewController {
@IBOutlet weak var aButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
aButton.setTitle("Press Me!", forState: .Normal)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
boris said
3,607 Pointsimport UIKit
class PlaylistMasterViewController: UIViewController {
@IBOutlet weak var aButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
aButton.setTitle("Press Me!", forState: .Normal)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
boris said
3,607 Pointsimport UIKit
class PlaylistMasterViewController: UIViewController {
@IBOutlet weak var aButton: UIButton!
override func viewDidLoad() {
super.viewDidLoad()
aButton.setTitle("Press Me!", forState: .Normal)
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
Chris Wolchesky
12,025 PointsYour class names aren't matching across files. According to the original error text it's looking for "PlayMasterViewController", but the code you posted is for "PlaylistMasterViewController".
2016-03-01 06:15:01.986 Algorhythm[48318:4052082] Unknown class PlayMasterViewController in Interface Builder file.
class PlaylistMasterViewController: UIViewController {
//...
}
Chris Wolchesky
12,025 PointsChris Wolchesky
12,025 PointsCan you post the source code for the associated error? Judging on the error text:
*** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[ setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key aButton.'I would guess that you're referencing a key on an object which does not have the associated key, but having the context of it's use would be helpful.