其中一个界面需要隐藏导航条

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];
    //隐藏导航条是要使用带有动画的方法
    [self.navigationController setNavigationBarHidden:YES animated:YES];
}

- (void)viewWillDisappear:(BOOL)animated
{
    [super viewWillDisappear:animated];
    [self.navigationController setNavigationBarHidden:NO animated:YES];
}