unrecognized selector sent to instance ***

Question

When I run the project, it crashes at "AppDelegate.swift".

The error message:

Optional(<UIButton: 0x7f9a0bd06610; frame = (0 0; 49 42); opaque = NO; autoresize = RM+BM; layer = <CALayer: 0x600001a316a0>>)
2019-04-07 11:10:54.335048+0800 IRIS iOS[60993:2979677] -[UIView setConstant:]: unrecognized selector sent to instance 0x7f9a0bd247f0
2019-04-07 11:10:54.351958+0800 IRIS iOS[60993:2979677] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[UIView setConstant:]: unrecognized selector sent to instance 0x7f9a0bd247f0'
*** First throw call stack:
(
    0   CoreFoundation                      0x00000001044ce6fb __exceptionPreprocess + 331
    1   libobjc.A.dylib                     0x0000000103a72ac5 objc_exception_throw + 48
    2   CoreFoundation                      0x00000001044ecab4 -[NSObject(NSObject) doesNotRecognizeSelector:] + 132
    3   UIKitCore                           0x000000010f950c3d -[UIResponder doesNotRecognizeSelector:] + 287
    4   CoreFoundation                      0x00000001044d3443 ___forwarding___ + 1443
    5   CoreFoundation                      0x00000001044d5238 _CF_forwarding_prep_0 + 120
    6   IRIS iOS                            0x000000010300cf1a $s8IRIS_iOS20SecondViewControllerC12isProcessingSbvW + 1418
    7   IRIS iOS                            0x000000010300d4c2 $s8IRIS_iOS20SecondViewControllerC12isProcessingSbvs + 274
    8   IRIS iOS                            0x000000010300d637 $s8IRIS_iOS20SecondViewControllerC11viewDidLoadyyF + 151
    9   IRIS iOS                            0x000000010300d844 $s8IRIS_iOS20SecondViewControllerC11viewDidLoadyyFTo + 36
    10  UIKitCore                           0x000000010f32243b -[UIViewController loadViewIfRequired] + 1183
    11  UIKitCore                           0x000000010f322868 -[UIViewController view] + 27
    12  UIKitCore                           0x000000010f95ac33 -[UIWindow addRootViewControllerViewIfPossible] + 122
    13  UIKitCore                           0x000000010f95b327 -[UIWindow _setHidden:forced:] + 289
    14  UIKitCore                           0x000000010f96df86 -[UIWindow makeKeyAndVisible] + 42
    15  UIKitCore                           0x000000010f91df1c -[UIApplication _callInitializationDelegatesForMainScene:transitionContext:] + 4555
    16  UIKitCore                           0x000000010f9230c6 -[UIApplication _runWithMainScene:transitionContext:completion:] + 1617
    17  UIKitCore                           0x000000010f1686d6 __111-[__UICanvasLifecycleMonitor_Compatability _scheduleFirstCommitForScene:transition:firstActivation:completion:]_block_invoke + 904
    18  UIKitCore                           0x000000010f170fce +[_UICanvas _enqueuePostSettingUpdateTransactionBlock:] + 153
    19  UIKitCore                           0x000000010f1682ec -[__UICanvasLifecycleMonitor_Compatability _scheduleFirstCommitForScene:transition:firstActivation:completion:] + 236
    20  UIKitCore                           0x000000010f168c48 -[__UICanvasLifecycleMonitor_Compatability activateEventsOnly:withContext:completion:] + 1091
    21  UIKitCore                           0x000000010f166fba __82-[_UIApplicationCanvas _transitionLifecycleStateWithTransitionContext:completion:]_block_invoke + 782
    22  UIKitCore                           0x000000010f166c71 -[_UIApplicationCanvas _transitionLifecycleStateWithTransitionContext:completion:] + 433
    23  UIKitCore                           0x000000010f16b9b6 __125-[_UICanvasLifecycleSettingsDiffAction performActionsForCanvas:withUpdatedScene:settingsDiff:fromSettings:transitionContext:]_block_invoke + 576
    24  UIKitCore                           0x000000010f16c610 _performActionsWithDelayForTransitionContext + 100
    25  UIKitCore                           0x000000010f16b71d -[_UICanvasLifecycleSettingsDiffAction performActionsForCanvas:withUpdatedScene:settingsDiff:fromSettings:transitionContext:] + 223
    26  UIKitCore                           0x000000010f1706d0 -[_UICanvas scene:didUpdateWithDiff:transitionContext:completion:] + 392
    27  UIKitCore                           0x000000010f9219a8 -[UIApplication workspace:didCreateScene:withTransitionContext:completion:] + 514
    28  UIKitCore                           0x000000010f4d8dfa -[UIApplicationSceneClientAgent scene:didInitializeWithEvent:completion:] + 361
    29  FrontBoardServices                  0x000000010d982125 -[FBSSceneImpl _didCreateWithTransitionContext:completion:] + 448
    30  FrontBoardServices                  0x000000010d98bed6 __56-[FBSWorkspace client:handleCreateScene:withCompletion:]_block_invoke_2 + 283
    31  FrontBoardServices                  0x000000010d98b700 __40-[FBSWorkspace _performDelegateCallOut:]_block_invoke + 53
    32  libdispatch.dylib                   0x0000000108294db5 _dispatch_client_callout + 8
    33  libdispatch.dylib                   0x00000001082982ba _dispatch_block_invoke_direct + 300
    34  FrontBoardServices                  0x000000010d9bd146 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 30
    35  FrontBoardServices                  0x000000010d9bcdfe -[FBSSerialQueue _performNext] + 451
    36  FrontBoardServices                  0x000000010d9bd393 -[FBSSerialQueue _performNextFromRunLoopSource] + 42
    37  CoreFoundation                      0x0000000104435be1 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    38  CoreFoundation                      0x0000000104435463 __CFRunLoopDoSources0 + 243
    39  CoreFoundation                      0x000000010442fb1f __CFRunLoopRun + 1231
    40  CoreFoundation                      0x000000010442f302 CFRunLoopRunSpecific + 626
    41  GraphicsServices                    0x000000010b4bb2fe GSEventRunModal + 65
    42  UIKitCore                           0x000000010f924ba2 UIApplicationMain + 140
    43  IRIS iOS                            0x000000010303135b main + 75
    44  libdyld.dylib                       0x0000000108309541 start + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException

Can someone please explain this, or at least, tell me what I need to write to get it correct?

You need to symbolicate the crash report so you can see the function names and line numbers of your own code. Then you'll know where in your code it is crashing. My guess is that you have a bad connection to an outlet or action. — rmaddy
As I said, you need to symbolicate it so you can see filenames and line numbers of your code. — rmaddy
I symbolicated it but I don't know which caused my project crash... Could you plz help me?@rmaddy — 齐子佳
you're calling setConstant on a UIView instance, you need to tell us how this view is being created. — Inder Kumar Rathore

Anil Kumar Anil Kumar · Accepted Answer · 2019-04-07T03:49:15

1

votes

Its mean you have create a button but its selector method has not created.

unrecognized selector sent to instance ***

1 Answers