如何返回上一个界面并传值给上一个界面

- (void) goBackToPersonInfoVCWithNickName:(NSString *) nickName{
//            [self.navigationController popViewControllerAnimated:YES];
//此页面已经存在于self.navigationController.viewControllers中,并且是当前页面的前一页面
PersonInfoViewController *personVC = [self.navigationController.viewControllers objectAtIndex:self.navigationController.viewControllers.count-2];
//初始化其属性
//            personVC.sexInt = _sex;
//传递参数过去
personVC.nickName = nickName;
//使用popToViewController返回并传值到上一页面
[self.navigationController popToViewController:personVC animated:true];

}