AlertView.m

// Observed bug(?): When adding a button after creating UIAlertView, the firstOtherButtonIndex value
// is stuck as -1 instead of the correct value, 1, even though the documentation states that the two
// invocations below should be equivalent.

NSString *closeText = @"Cancel";
NSString *actionText = @"OK";

UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title
                                                    message:message
                                                   delegate:self
                                          cancelButtonTitle:closeText
                                          otherButtonTitles:nil];
if (actionText) {
    [alertView addButtonWithTitle:actionText];
}
NSLog(@"alertView cancel:%ld firstOther:%ld", (long)alertView.cancelButtonIndex, (long)alertView.firstOtherButtonIndex);
// alertView cancel:0 firstOther:-1

UIAlertView *alertView = [[UIAlertView alloc] initWithTitle:title
                                                    message:message
                                                   delegate:self
                                          cancelButtonTitle:closeText
                                          otherButtonTitles:actionText, nil];
NSLog(@"alertView cancel:%ld firstOther:%ld", (long)alertView.cancelButtonIndex, (long)alertView.firstOtherButtonIndex);
// alertView cancel:0 firstOther:1

otherButtonTitles.md

The Apple documentation on otherButtonTitles has this to say:

The title of another button.
Using this argument is equivalent to invoking addButtonWithTitle: with this title to add more buttons.