弹出带输入框的alertView

addTask

- (void)addTaskButtonClicked:(id)sender
{
    UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:NSLocalizedString(@"NewTaskTitle", @"")
                                                        message:@""
                                                       delegate:self
                                              cancelButtonTitle:NSLocalizedString(@"NewTaskCancel", @"")
                                              otherButtonTitles:NSLocalizedString(@"NewTaskConfirm", @""), nil];
    alertView.delegate = self;
    alertView.tag = 0;
    alertView.alertViewStyle = UIAlertViewStylePlainTextInput;
    UITextField* alertTextField = [alertView textFieldAtIndex:0];
    alertTextField.placeholder = NSLocalizedString(@"NewTaskPlaceholder", @"");
    [alertView show];
}

#pragma mark - UIAlertViewDelegate
- (void)alertView:(UIAlertView*)alertView clickedButtonAtIndex:(NSInteger)buttonIndex
{
    if (alertView.tag == 0) {
        UITextField* alertTextField = [alertView textFieldAtIndex:0];
        if (buttonIndex == 1) {
            NSString* taskName = alertTextField.text;
            if (taskName.length > 0) {
                [[self.allViewControllers objectAtIndex:1] addTask:taskName];
            }
        }
        [alertTextField resignFirstResponder];
    }
}