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iOS Build a Playlist Browser with Swift Refactoring Our Code Passing Playlist Objects Using Segues

Posted by Nicholas Barmore
Nicholas Barmore
2,074 Points

SIGABRT Error causing app to Crash after click

My app is crashing after the first click and im recieving a signal SIGABRT error in this line of code

class AppDelegate: UIResponder, UIApplicationDelegate {

Can anyone help?

Steven Deutsch
Steven Deutsch
21,046 Points
Steven Deutsch
Steven Deutsch
21,046 Points

Hey Nicholas,

Can you post the debugger output for me? Thanks.

Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

Start by adding an exception break point, then run the code again and see where the error is happening.

2 Answers

jcorum
jcorum
71,830 Points
jcorum
jcorum
71,830 Points

Nicholas, usually at this level SIGABRT means that some control that used to be connected to an outlet or an action isn't. Check each outlet and action. There should be a bull's eye in the gutter next to each one. If there is just a circle, rather than a bull's eye, it means the connection has gone astray. There are other ways to check as well. You can right click on a control and check the popup window. You can select the control and look in the Connections inspector. Bottom line, if controls and outlets and actions don't line up correctly, you'll see this error.

Nicholas Barmore
Nicholas Barmore
2,074 Points
Nicholas Barmore
Nicholas Barmore
2,074 Points 
@[Steven Deutsch](https://teamtreehouse.com/whoswho) 2016-03-01 17:06:44.285 Algorhythm[8617:22707073] -[Algorhythm.PlaylistMasterViewController showPlaylistDetailSegue:]: unrecognized selector sent to instance 0x7fc2d8410910
2016-03-01 17:06:44.288 Algorhythm[8617:22707073] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[Algorhythm.PlaylistMasterViewController showPlaylistDetailSegue:]: unrecognized selector sent to instance 0x7fc2d8410910'
*** First throw call stack:
(
    0   CoreFoundation                      0x000000010cb4ce65 __exceptionPreprocess + 165
    1   libobjc.A.dylib                     0x000000010e88cdeb objc_exception_throw + 48
    2   CoreFoundation                      0x000000010cb5548d -[NSObject(NSObject) doesNotRecognizeSelector:] + 205
    3   CoreFoundation                      0x000000010caa290a ___forwarding___ + 970
    4   CoreFoundation                      0x000000010caa24b8 _CF_forwarding_prep_0 + 120
    5   UIKit                               0x000000010d851e73 _UIGestureRecognizerSendTargetActions + 153
    6   UIKit                               0x000000010d84e4e5 _UIGestureRecognizerSendActions + 162
    7   UIKit                               0x000000010d84c4e2 -[UIGestureRecognizer _updateGestureWithEvent:buttonEvent:] + 843
    8   UIKit                               0x000000010d8549a0 ___UIGestureRecognizerUpdate_block_invoke904 + 79
    9   UIKit                               0x000000010d85483e _UIGestureRecognizerRemoveObjectsFromArrayAndApplyBlocks + 342
    10  UIKit                               0x000000010d842101 _UIGestureRecognizerUpdate + 2634
    11  UIKit                               0x000000010d3d9f8a -[UIWindow _sendGesturesForEvent:] + 1137
    12  UIKit                               0x000000010d3db1c0 -[UIWindow sendEvent:] + 849
    13  UIKit                               0x000000010d389b66 -[UIApplication sendEvent:] + 263
    14  UIKit                               0x000000010d363d97 _UIApplicationHandleEventQueue + 6844
    15  CoreFoundation                      0x000000010ca78a31 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
    16  CoreFoundation                      0x000000010ca6e95c __CFRunLoopDoSources0 + 556
    17  CoreFoundation                      0x000000010ca6de13 __CFRunLoopRun + 867
    18  CoreFoundation                      0x000000010ca6d828 CFRunLoopRunSpecific + 488
    19  GraphicsServices                    0x000000011115fad2 GSEventRunModal + 161
    20  UIKit                               0x000000010d369610 UIApplicationMain + 171
    21  Algorhythm                          0x000000010c956ccd main + 109
    22  libdyld.dylib                       0x000000010f39592d start + 1
    23  ???                                 0x0000000000000001 0x0 + 1
)
libc++abi.dylib: terminating with uncaught exception of type NSException
(lldb)
Steven Deutsch
Steven Deutsch
21,046 Points
Steven Deutsch
Steven Deutsch
21,046 Points

Right click on your view controller in storyboard (the yellow circle) and check that the IBActions and IBOutlets are set up properly. Make sure you don't have any orphaned outlets. Make sure your segue has the same identifier that is being used in prepareForSegue.