警报框出现时如何使键盘停留？

Question

I want to check if the value of a textfield is valid, if not, an alert box will pop up. Here is my code:

- (IBAction) done: (id) sender{
    if (!test) {
        UIAlertView *alert = [[UIAlertView alloc]init....];
        [alert show];
        [alert release];
        [textfield becomeFirstResponder];
    }
    else{
        [sender resignFirstResponder];
        //doing stuff;
    }
}

Currently the alert box works fine, but when I dismiss the alert box, the focus doesn't get back to the textfield that I specified. Any idea where I did wrong?

Answer 1

You can implement UIAlertView's -alertView:didDismissWithButtonIndex: delegate method, which is called every time when alert view gets dismissed:

- (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex {
    [textField becomeFirstResponder];
}