隐藏导航栏或返回按钮

1 - (void)viewWillAppear:(BOOL)animated
2 {
3    [super viewWillAppear:animated];
4    [self.navigationController setNavigationBarHidden:YES animated:YES]; // 隐藏导航栏
5    [self.navigationItemsetHidesBackButton:YES];   // 隐藏返回按钮
5 }

左右键则可以用 
self.navigationItem.leftBarButtonItem.hidden = YES;