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iOS

Posted by Aaron Yow
Aaron Yow
Courses Plus Student 8,262 Points

app crashed while testing

not sure whats wrong with it but this came up

2015-10-17 15:21:55.391 Stormy[2887:91184] *** Terminating app due to uncaught exception 'NSUnknownKeyException', reason: '[<Stormy.ViewController 0x7fc0aa67de60> setValue:forUndefinedKey:]: this class is not key value coding-compliant for the key currentHumudityLabel.'
*** First throw call stack:
(
    0   CoreFoundation                      0x0000000109cf1f65 __exceptionPreprocess + 165
    1   libobjc.A.dylib                     0x000000010b983deb objc_exception_throw + 48
    2   CoreFoundation                      0x0000000109cf1ba9 -[NSException raise] + 9
    3   Foundation                          0x000000010a0b9f5b -[NSObject(NSKeyValueCoding) setValue:forKey:] + 288
    4   UIKit                               0x000000010a68fd40 -[UIViewController setValue:forKey:] + 88
    5   UIKit                               0x000000010a8ac923 -[UIRuntimeOutletConnection connect] + 109
    6   CoreFoundation                      0x0000000109c32b10 -[NSArray makeObjectsPerformSelector:] + 224
    7   UIKit                               0x000000010a8ab306 -[UINib instantiateWithOwner:options:] + 1864
    8   UIKit                               0x000000010a69684d -[UIViewController _loadViewFromNibNamed:bundle:] + 381
    9   UIKit                               0x000000010a697179 -[UIViewController loadView] + 178
    10  UIKit                               0x000000010a69747c -[UIViewController loadViewIfRequired] + 139
    11  UIKit                               0x000000010a697c7d -[UIViewController view] + 27
    12  UIKit                               0x000000010a5750c0 -[UIWindow addRootViewControllerViewIfPossible] + 61
    13  UIKit                               0x000000010a5757bd -[UIWindow _setHidden:forced:] + 302
    14  UIKit                               0x000000010a587020 -[UIWindow makeKeyAndVisible] + 43
    15  UIKit                               0x000000010a50493c -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 4131
    16  UIKit                               0x000000010a50ae15 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1755
    17  UIKit                               0x000000010a507ff0 -[UIApplication workspaceDidEndTransaction:] + 188
    18  FrontBoardServices                  0x000000010d81a7ac -[FBSSerialQueue _performNext] + 192
    19  FrontBoardServices                  0x000000010d81ab1a -[FBSSerialQueue _performNextFromRunLoopSource] + 45
    20  CoreFoundation                      0x0000000109c1e0a1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    21  CoreFoundation                      0x0000000109c13fcc __CFRunLoopDoSources0 + 556
    22  CoreFoundation                      0x0000000109c13483 __CFRunLoopRun + 867
    23  CoreFoundation                      0x0000000109c12e98 CFRunLoopRunSpecific + 488
    24  UIKit                               0x000000010a50798d -[UIApplication _run] + 402
    25  UIKit                               0x000000010a50c676 UIApplicationMain + 171
    26  Stormy                              0x0000000109b1358d main + 109
    27  libdyld.dylib                       0x000000010c49b92d start + 1
    28  ???                                 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)

1 Answer

ianhan3
ianhan3
4,263 Points
ianhan3
ianhan3
4,263 Points

There are tons of reasons why the app may have crashed with that error so we would need a bit more info on exactly. Check out the error handling section, "Debugging Our App" in the "Build a Simple iPhone App" for an example of this error and how to go about figuring out exactly what is wrong.

Most commonly (for me at least), this is caused by you deleting a button and not disconnecting the other side. So for example if I created a button in interface builder, connected it to my ViewController.swift file then decided I didn't want the button, yet only deleted it from the storyboard, I would get this error. Check your buttons for extraneous connections by right clicking them or looking in the connections inspector.