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

Posted by Antoine Delanglade
Antoine Delanglade
2,325 Points

Runtime error when pressing the button

I have an error when pressing the button:

2015-07-23 17:31:02.984 PlaylistApp[24755:2945055] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<PlaylistApp.ViewController 0x7ffb40e2a630> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key aButton.' *** First throw call stack: ( 0 CoreFoundation 0x000000010eb58c65 exceptionPreprocess + 165 1 libobjc.A.dylib 0x00000001106c3bb7 objc_exception_throw + 45 2 CoreFoundation 0x000000010eb588a9 -[NSException raise] + 9 3 Foundation 0x000000010ef76b53 -[NSObject(NSKeyValueCoding) setValue:forKey:] + 259 4 CoreFoundation 0x000000010eaa0d50 -[NSArray makeObjectsPerformSelector:] + 224 5 UIKit 0x000000010f6cf4eb -[UINib instantiateWithOwner:options:] + 1506 6 UIKit 0x000000010f5276d8 -[UIViewController _loadViewFromNibNamed:bundle:] + 242 7 UIKit 0x000000010f527cc8 -[UIViewController loadView] + 109 8 UIKit 0x000000010f527f39 -[UIViewController loadViewIfRequired] + 75 9 UIKit 0x000000010f5283ce -[UIViewController view] + 27 10 UIKit 0x000000010f443289 -[UIWindow addRootViewControllerViewIfPossible] + 58 11 UIKit 0x000000010f44364f -[UIWindow _setHidden:forced:] + 247 12 UIKit 0x000000010f44fde1 -[UIWindow makeKeyAndVisible] + 42 13 UIKit 0x000000010f3f3417 -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 2732 14 UIKit 0x000000010f3f619e -[UIApplication _runWithMainScene:transitionContext:completion:] + 1349 15 UIKit 0x000000010f3f5095 -[UIApplication workspaceDidEndTransaction:] + 179 16 FrontBoardServices 0x00000001121c05e5 __31-[FBSSerialQueue performAsync:]_block_invoke_2 + 21 17 CoreFoundation 0x000000010ea8c41c __CFRUNLOOP_IS_CALLING_OUT_TO_A_BLOCK + 12 18 CoreFoundation 0x000000010ea82165 __CFRunLoopDoBlocks + 341 19 CoreFoundation 0x000000010ea81f25 __CFRunLoopRun + 2389 20 CoreFoundation 0x000000010ea81366 CFRunLoopRunSpecific + 470 21 UIKit 0x000000010f3f4b02 -[UIApplication _run] + 413 22 UIKit 0x000000010f3f78c0 UIApplicationMain + 1282 23 PlaylistApp 0x000000010e9714d7 main + 135 24 libdyld.dylib 0x0000000110df9145 start + 1 25 ??? 0x0000000000000001 0x0 + 1 ) libc++abi.dylib: terminating with uncaught exception of type NSException (lldb)

It's not the first time I run into this issue. I already experienced it further in this project though I thought it was because I messed up something. So I started it over and follow each step carefully but I still got that. Any idea where this comes from?