Question

In my iPhone app, I have a NSObjectA class and a UIViewController B class. I want to call a instance method in B class from A. I used the following code.

Bclass *vc = [[Bclass alloc]init];
[vc hideAlert:NSString];
[vc release];

and in B class:

- (void)hideAlert:(NSString*)message{
    UIAlertView *shareAlrt = [[UIAlertView alloc] initWithTitle:@""
                                                        message:message
                                                       delegate:self
                                              cancelButtonTitle:@"Ok"
                                              otherButtonTitles:nil];
    [shareAlrt show];
    [shareAlrt release];
}

and the method called and show a AlertView. When click on the Ok button, I want to navigate to class Cclass.

- (void)alertView:(UIAlertView *)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    if (buttonIndex == 0)
    {
        Cclass *vc = [[Cclass alloc]initWithNibName:@"Cclass" bundle:[NSBundle mainBundle]];
        [self presentModalViewController:vc animated:NO];
        [vc release];
    }
}

But when I click on the Ok button, the app crashes. Whats happening here? I have added <UIAlertViewDelegate> in the B class.h file, but still the same error. Please help

I am getting the error code *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFType alertView:clickedButtonAtIndex:]: unrecognized selector sent to instance 0x81baa80'

Answer 1

Just change the method

- (void)hideAlert:(NSString*)message{
    UIAlertView *shareAlrt = [[UIAlertView alloc] initWithTitle:@""
                                                    message:message
                                                   delegate:self
                                          cancelButtonTitle:nil
                                          otherButtonTitles:@"Ok",nil];
    [shareAlrt show];
    [shareAlrt release];
}