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iOS Build a Playlist Browser with Swift Working With Multiple View Controllers Recap of iOS Basics

Jason Poole
Jason Poole
46,159 Points
Posted by Jason Poole
Jason Poole
46,159 Points

Terminating app due to uncaught exception 'NSUnknownKeyException'

Using the downloadable project files and Xcode throws the following:

2015-10-29 06:16:30.402 Algorhythm[1339:340471] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<Algorhythm.ViewController 0x7ff200c403f0> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key Button.' *** First throw call stack: ( 0 CoreFoundation 0x0000000106820f45 exceptionPreprocess + 165 1 libobjc.A.dylib 0x0000000108544deb objc_exception_throw + 48 2 CoreFoundation 0x0000000106820b89 -[NSException raise] + 9 3 Foundation 0x0000000106be9a6b -[NSObject(NSKeyValueCoding) setValue:forKey:] + 288 4 UIKit 0x00000001071c804c -[UIViewController setValue:forKey:] + 88 5 UIKit 0x00000001073f5a71 -[UIRuntimeOutletConnection connect] + 109 6 CoreFoundation 0x0000000106761a80 -[NSArray makeObjectsPerformSelector:] + 224 7 UIKit 0x00000001073f4454 -[UINib instantiateWithOwner:options:] + 1864 8 UIKit 0x00000001071cec16 -[UIViewController _loadViewFromNibNamed:bundle:] + 381 9 UIKit 0x00000001071cf542 -[UIViewController loadView] + 178 10 UIKit 0x00000001071cf8a0 -[UIViewController loadViewIfRequired] + 138 11 UIKit 0x00000001071d0013 -[UIViewController view] + 27 12 UIKit 0x00000001070a951c -[UIWindow addRootViewControllerViewIfPossible] + 61 13 UIKit 0x00000001070a9c05 -[UIWindow _setHidden:forced:] + 282 14 UIKit 0x00000001070bb4a5 -[UIWindow makeKeyAndVisible] + 42 15 UIKit 0x0000000107035396 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 4131 16 UIKit 0x000000010703b9c3 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1750 17 UIKit 0x0000000107038ba3 -[UIApplication workspaceDidEndTransaction:] + 188 18 FrontBoardServices 0x000000010a3d3784 -[FBSSerialQueue _performNext] + 192 19 FrontBoardServices 0x000000010a3d3af2 -[FBSSerialQueue _performNextFromRunLoopSource] + 45 20 CoreFoundation 0x000000010674d011 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION + 17 21 CoreFoundation 0x0000000106742f3c __CFRunLoopDoSources0 + 556 22 CoreFoundation 0x00000001067423f3 __CFRunLoopRun + 867 23 CoreFoundation 0x0000000106741e08 CFRunLoopRunSpecific + 488 24 UIKit 0x00000001070384f5 -[UIApplication _run] + 402 25 UIKit 0x000000010703d30d UIApplicationMain + 171 26 Algorhythm 0x000000010664450d main + 109 27 libdyld.dylib 0x000000010904c92d start + 1 ) libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)