- (IBAction)saveEmailAction:(id)sender {             if ([self  isValidateEmail:_mailField.text])             {                 [self.delegate saveEmail:_mailField.text];                 [self.navigationController popViewControllerAnimated:YES];             }            else            {                UIAlertView *error=[[UIAlertView alloc]initWithTitle:@"提示" message:@"请输入正确邮箱" delegate:self cancelButtonTitle:@"确定" otherButtonTitles:nil];                [error show];            }        }                        -(BOOL)isValidateEmail:(NSString *)email {            NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";            NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];            return [emailTest evaluateWithObject:email];        }