SIGABRT Xcode??? Help Needed - ios

Question

I am currently a new developer, and I came across this error; SIGABRT. I have tried developing many apps, and a lot of them get this error. I am developing a sound matching educational app for little kids where they use one picker view in Xcode to match an animal and their sound. My code is as follows:
ViewController.m
#define componentCount 2
#define animalComponent 0
#define soundComponent 1
#import "ViewController.h"
#interface ViewController ()
#end
#implementation ViewController
#synthesize lastAction;
#synthesize matchResult;
- (void)pickerView:(UIPickerView *)pickerView didSelectRow:(NSInteger)row inComponent:(NSInteger)component {
NSString *actionMessage;
NSString *matchMessage;
int selectedAnimal;
int selectedSound;
int matchedSound;
if (component==animalComponent) {
actionMessage=[[NSString alloc]
initWithFormat:#"You Selected The Animal Named '%#'!",
[animalNames objectAtIndex:row]];
} else {
actionMessage=[[NSString alloc]
initWithFormat:#"You Selected The Animal Sound '%#'!",
[animalSounds objectAtIndex:row]];
}
selectedAnimal=[pickerView selectedRowInComponent:animalComponent];
selectedSound=[pickerView selectedRowInComponent:soundComponent];
matchedSound=([animalSounds count] - 1) -
[pickerView selectedRowInComponent:soundComponent];
if (selectedAnimal==matchedSound) {
matchMessage=[[NSString alloc] initWithFormat:#"Yes, A '%#' Does Go '%#'!"];
[animalNames objectAtIndex:selectedAnimal],
[animalSounds objectAtIndex:selectedSound];
} else {
matchMessage=[[NSString alloc] initWithFormat:#"No, A '%#' Doesn't Go '%#'!"];
[animalNames objectAtIndex:selectedAnimal],
[animalSounds objectAtIndex:selectedSound];
}
lastAction.text=actionMessage;
matchResult.text=matchMessage;
[matchMessage release];
[actionMessage release];
}
- (NSString *)pickerView:(UIPickerView *)pickerView titleForRow:(NSInteger)row forComponent:(NSInteger)component {
if (component==animalComponent) {
return [animalNames objectAtIndex:row];
} else {
return [animalSounds objectAtIndex:row];
}
}
- (NSInteger)pickerView:(UIPickerView *)pickerView numberOfRowsInComponent:(NSInteger)component {
if (component==animalComponent) {
return [animalNames count];
} else {
return [animalSounds count];
}
}
- (void)dealloc {
[animalNames release];
[animalSounds release];
[lastAction release];
[matchResult release];
[super dealloc];
}
- (void)viewDidLoad {
animalNames=[[NSArray alloc]initWithObjects:
#"Cat", #"Dog", #"Snake", #"Cow", #"Horse", #"Pig", #"Duck", #"Sheep", #"Bird",nil];
animalSounds=[[NSArray alloc]initWithObjects:
#"Chirp", #"Baa", #"Quack", #"Oink", #"Nay", #"Moo", #"Hiss", #"Bark", #"Purr",nil];
[super viewDidLoad];
// Do any additional setup after loading the view, typically from a nib.
}
- (void)viewDidUnload{
[super viewDidUnload];
// Release any retained subviews of the main view.
}
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
return (interfaceOrientation != UIInterfaceOrientationPortraitUpsideDown);
}
#end
ViewController.h
#import <UIKit/UIKit.h>
#interface ViewController : UIViewController <UIPickerViewDataSource, UIPickerViewDelegate> {
NSArray *animalNames;
NSArray *animalSounds;
IBOutlet UILabel *lastAction;
IBOutlet UILabel *matchResult;
}
#property (nonatomic, retain) UILabel *lastAction;
#property (nonatomic, retain) UILabel *matchResult;
#end
Where The SIGABRT Is
#import <UIKit/UIKit.h>
#import "AppDelegate.h"
int main(int argc, char *argv[])
{
#autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
//at end of row of code above this, there was the error message: signal SIGABRT
}
}
Anyways, I absolutely need help on what I should do in order to get rid of this SIGABRT error. Thank you.

Answer 1

You have to identify the line of code that is causing the problem, something we cannot identify from the snippet of code.
You may want to enable exception breakpoints, as they often can identify the precise exact line of code that is causing the exception. When I encounter exceptions in my development, I'll simply add an exception breakpoint on "All" exceptions (see Breakpoint Navigator Help or the screen snapshot below). That way, if I'm running the program through my debugger, when it encounters an exception, it will stop the code at the offending line, greatly simplifying the process of identifying the source of the problem. It doesn't always work perfectly, but it frequently finds the source of the exception more quickly than other techniques.
For a broader discussion on debugging apps (e.g. using the debugger to single step through your code, see the Xcode User Guide: Debug your App. If you know the problem is in this method, you might want to step through your code, line by line, and the problem will become self-evident.
I'd also suggest you check out My App Crashed, Now What on the Ray Wenderlich site.

Answer 2

You seem to have some formatting issues with your match message:
matchMessage=[[NSString alloc] initWithFormat:#"Yes, A '%#' Does Go '%#'!"];
[animalNames objectAtIndex:selectedAnimal],
[animalSounds objectAtIndex:selectedSound];
I'm surprised the compiler will actually compile this, but anyhow - you need to include the selected strings within the method call stringWithFormat:
Try below:
matchMessage = [[NSString alloc] initWithFormat:#"Yes, A '%#' Does Go '%#'!",
[animalNames objectAtIndex:selectedAnimal],
[animalSounds objectAtIndex:selectedSound]
];
Your compiler will definitely be giving you a warning about this. So your first step should always be to fix the compiler warnings. It's good practice to turn on the 'Treat warnings as errors' option in build settings. This means that the compiler is very strict about what it will accept and run - which means that you have to fix the warnings. There's really no excuse for having warnings from your compiler.

Answer 3

Read the english before the first call stack. What does it tell you? The most common form of sigabrt is where an IBOutlet gets deleted in the .h file and the outlet connection is still there in the storyboard. To solve this, delete all outlet connections in the storyboard, rewrite the IBOutlets, and link them over again.