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iOS Build a Simple iPhone App with Objective-C Creating a Data Model Using a Data Collection

Build a Simple iPhone App - Using a Data Collection, Ugly Error (Thread 1: signal SIGABRT)

Hey guys,

I'm scooting along nicely with the Build a Simple iPhone App project until now. I have followed along with the videos perfectly and everything works just fine alas all good runs must come to an end.

I have no errors or warnings with my code and when I run the Fun Facts app, I get a Thread 1: signal SIGABRT error and the app crashes when I tap the "Show Another Fun Fact" button.

I have scratched my head and can't find away to fix this so I thought it's time to get on the forum.

Here is my code that I have done for the project along with the console log of the bug.


#import <UIKit/UIKit.h>

@interface ViewController : UIViewController

@property (weak, nonatomic) IBOutlet UILabel *funFactLabel;
@property (strong, nonatomic) NSArray *facts;



#import "ViewController.h"

@interface ViewController ()


@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.facts = [[NSArray alloc] initWithObjects:@"Ants stretch when they wake.", @"Ostriches can run faster than horses.", nil];
    self.funFactLabel = [self.facts objectAtIndex:0];

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.

- (IBAction)showFunFact {

    self.funFactLabel.text = [self.facts objectAtIndex:1];



Console Message

2015-05-17 01:19:17.586 FunFacts[2534:102474] -[__NSCFConstantString setText:]: unrecognized selector sent to instance 0x10203c
2015-05-17 01:19:17.589 FunFacts[2534:102474] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFConstantString setText:]: unrecognized selector sent to instance 0x10203c'
*** First throw call stack:
    0   CoreFoundation                      0x0095a746 __exceptionPreprocess + 182
    1   libobjc.A.dylib                     0x005e3a97 objc_exception_throw + 44
    2   CoreFoundation                      0x00962705 -[NSObject(NSObject) doesNotRecognizeSelector:] + 277
    3   CoreFoundation                      0x008a9287 ___forwarding___ + 1047
    4   CoreFoundation                      0x008a8e4e _CF_forwarding_prep_0 + 14
    5   FunFacts                            0x00100840 -[ViewController showFunFact] + 176
    6   libobjc.A.dylib                     0x005f97cd -[NSObject performSelector:withObject:withObject:] + 84
    7   UIKit                               0x00d1aa90 -[UIApplication sendAction:to:from:forEvent:] + 99
    8   UIKit                               0x00d1aa22 -[UIApplication sendAction:toTarget:fromSender:forEvent:] + 64
    9   UIKit                               0x00e5b18a -[UIControl sendAction:to:forEvent:] + 69
    10  UIKit                               0x00e5b5a7 -[UIControl _sendActionsForEvents:withEvent:] + 598
    11  UIKit                               0x00e5a811 -[UIControl touchesEnded:withEvent:] + 660
    12  UIKit                               0x00d72cfa -[UIWindow _sendTouchesForEvent:] + 874
    13  UIKit                               0x00d737d6 -[UIWindow sendEvent:] + 792
    14  UIKit                               0x00d316d1 -[UIApplication sendEvent:] + 242
    15  UIKit                               0x00d41b08 _UIApplicationHandleEventFromQueueEvent + 21484
    16  UIKit                               0x00d15337 _UIApplicationHandleEventQueue + 2300
    17  CoreFoundation                      0x0087c06f __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 15
    18  CoreFoundation                      0x00871b7d __CFRunLoopDoSources0 + 253
    19  CoreFoundation                      0x008710d8 __CFRunLoopRun + 952
    20  CoreFoundation                      0x00870a5b CFRunLoopRunSpecific + 443
    21  CoreFoundation                      0x0087088b CFRunLoopRunInMode + 123
    22  GraphicsServices                    0x03bc02c9 GSEventRunModal + 192
    23  GraphicsServices                    0x03bc0106 GSEventRun + 104
    24  UIKit                               0x00d19106 UIApplicationMain + 1526
    25  FunFacts                            0x00100d3a main + 138
    26  libdyld.dylib                       0x02ce6ac9 start + 1
    27  ???                                 0x00000001 0x0 + 1
libc++abi.dylib: terminating with uncaught exception of type NSException

Don't know if it is due to a lack of caffine, but no doubt I have missed something dumb out, like the good old ;

Any advice or help on this would be greatly appreciated as I'm really enjoying this course and I'd rather be doing it than sitting idle looking for a fix.

Thanking you in advance,

Stu : D

Jeanne Merle
Jeanne Merle
3,390 Points

Try to delete bad Referencing outlets : this caused me the same error than you.

For this, click on your MainStoryboard at the right of the screen, open the Utilities panel click on the right button "Show the connections inspector" (an arrow in a circle) then here check your references . Delete the ones you don't use anymore. Be careful to not delete the ones you use in your ViewController.swift.

Good Luck.

I re-assed my code against what Passan had done in the project and I have managed to get it to work, I think I may have put some code in the wrong spot, because it seems to be doing what it's meant to be doing now :)

Thanks for your help too Jeanne Merle! : )

2 Answers

Ayush Bhargava
Ayush Bhargava
791 Points

there was only one reference in my reference outlet called viewcontroler and i deleted it but when i tried it again it didn't work the same problem occurred it is almost the same as stu's

Emmanuel Darmon
Emmanuel Darmon
6,115 Points

Same problem here but Jeanne Merle had the solution: Go to storyboard, right click on "Show another fun fact" and uncheck extra. It works fine now!