“unrecognized selector sent to instance” error in

Question

I created a button and added an action for it, but as soon as it invoked, I got this error:

-[NSCFDictionary numberButtonClick:]: unrecognized selector sent to instance
 0x3d03ac0 2010-03-16 22:23:58.811
 Money[8056:207] *** Terminating app
 due to uncaught exception
 'NSInvalidArgumentException', reason:'*** -[NSCFDictionary numberButtonClick:]:  unrecognized selector sent to instance 0x3d03ac0'

This is my code:

- (id)initWithNibName:(NSString *)nibNameOrNil bundle:(NSBundle *)nibBundleOrNil {
    if (self = [super initWithNibName:nibNameOrNil bundle:nibBundleOrNil]) {
        UIButton *numberButton = [UIButton buttonWithType:UIButtonTypeCustom];        
        numberButton.frame = CGRectMake(10, 435, 46, 38);
        [numberButton setImage:[UIImage imageNamed:@"one.png"] forState:UIControlStateNormal];
        [numberButton addTarget:self action:@selector(numberButtonClick:) forControlEvents:UIControlEventTouchUpInside];
        [self.view addSubview: numberButton]; 
    }
return self;
}

-(IBAction)numberButtonClick:(id)sender{
    NSLog(@"---");
}

Answer 1

This happened to my because accidentally erase the " @IBAction func... " inside my UIViewcontroller class code, so in the Storyboard was created the Reference Outlet, but at runtime there was any function to process it.

The solution was to delete the Outlet reference inside the property inspector and then recreate it dragging with command key to the class code.

Hope it helps!

Answer 2

I also had the same issue.

I deleted my uibutton in my storyboard and recreated it .. now everything works fine.

Answer 3

OK, I have to chip in here. The OP dynamically created the button. I had a similar issue and the answer (after hours of hunting) is so simple it made me sick.

When using:

action:@selector(xxxButtonClick:)

or (as in my case)

action:NSSelectorFromString([[NSString alloc] initWithFormat:@"%@BtnTui:", name.lowercaseString])

If you place a colon at the end of the string - it will pass the sender. If you do not place the colon at the end of the string it will not, and the receiver will get an error if it expects one. It is easy to miss the colon if you are dynamically creating the event name.

The receiver code options look like this:

- (void)doneBtnTui:(id)sender {
  NSLog(@"Done Button - with sender");
}
 or
- (void)doneBtnTui {
  NSLog(@"Done Button - no sender");
}

As usual, it is always the obvious answer that gets missed.

Answer 4

I had this problem with a Swift project where I'm creating the buttons dynamically. Problem code:

var trashBarButtonItem: UIBarButtonItem {
    return UIBarButtonItem(barButtonSystemItem: .Add, target: self, action: "newButtonClicked")
}

func newButtonClicked(barButtonItem: UIBarButtonItem) {
    NSLog("A bar button item on the default toolbar was clicked: \(barButtonItem).")
}

The solution was to add a full colon ':' after the action: e.g.

var trashBarButtonItem: UIBarButtonItem {
        return UIBarButtonItem(barButtonSystemItem: .Add, target: self, action: "newButtonClicked:")
    }

    func newButtonClicked(barButtonItem: UIBarButtonItem) {
        NSLog("A bar button item on the default toolbar was clicked: \(barButtonItem).")
    }

Full example here: https://developer.apple.com/library/content/samplecode/UICatalog/Listings/Swift_UIKitCatalog_DefaultToolbarViewController_swift.html

Answer 5

For me, it was a leftover connection created in interfacebuilder bij ctrl-dragging. The name of the broken connection was in the error-log

*** Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '-[NameOfYourApp.NameOfYourClass nameOfCorruptConnection:]:
unrecognized selector sent to instance 0x7f97a48bb000'

I had an action linked to a button. Pressing the button crashed the app because the Outlet no longer existed in my code. Searching for the name in the log led me to it in the storyboard. Deleted it, and the crash was gone!

Answer 6

It can happen when you do not assign the ViewController to the ViewControllerScene in the InterfaceBuilder. So the ViewController.m is not connected to any scene.