Reputation: 6614

UIButton that's created programmatically crashing when method called

I have a rootViewController and have a UIButton that's created programmatically. I want this UIButton to display another view controller. For some reason it crashes with the following error:

Undefined symbols for architecture i386:
"_OBJC_CLASS_$_TutorialViewController", referenced from: objc-class-ref in RootViewController.o ld: symbol(s) not found for architecture i386 collect2: ld returned 1 exit status

here's the code that creates an Info UIButton. this code is in the loadView method:

 // Create a Button to get Help          
 UIButton *helpButton =  [UIButton buttonWithType:UIButtonTypeInfoDark ] ;
 CGRect buttonRect = helpButton.frame;

 // CALCulate the bottom right corner
 buttonRect.origin.x = self.view.frame.size.width - buttonRect.size.width - 8;
 buttonRect.origin.y = buttonRect.size.height - 8; 
 [helpButton setFrame:buttonRect];

 [helpButton addTarget:self action:@selector(doHelp:) forControlEvents:UIControlEventTouchUpInside];
 [self.view addSubview:helpButton];

}

Here's the action to transisition to another view controller:

- (IBAction)doHelp:(id)sender{
 NSLog(@"help button pressed");

 TutorialViewController *sampleView = [[[TutorialViewController alloc] init] autorelease];
 [sampleView setModalTransitionStyle:UIModalTransitionStyleFlipHorizontal];
 [self presentModalViewController:sampleView animated:YES];
}

thanks for any help.

Upvotes: 0

Answers (6)

Krunal

Reputation: 1328

I think instead of (IBAction), you must write (void)

Upvotes: -1

Hardik rami

Reputation: 341

instead of (IBAction)doHelp:(id)sender you must write (void)doHelp....try this:)

Upvotes: 1

Sanket

Reputation: 307

very basic but somtime we may miss it :) have you declared same method in .h file?

Upvotes: 0

burlyearly

Reputation: 316

adig is probably right.

Also, that technically isn't a "crash." It "fails to build, with this linker error." You can tell that it's a linker error because it said, "ld returned 1 exit status". ld is the linker.

Under the covers, XCode compiles and links your code before running it. If it fails during compilation or linking, it's a "build failure," not a "crash." A crash is when the application built, but then suddenly stopped at run time. One common cause of this is accessing a nil pointer.

Upvotes: 5