#ViewController.m

- (void)viewWillAppear:(BOOL)animated{

    [super viewWillAppear:animated];

    UIViewController *rootView = [[UIViewController alloc] init];

    rootView.title = @"Root View";

    self.navController = [[UINavigationController alloc] init];

    [self.navController pushViewController:rootView animated:YES];

    [self.view addSubview:self.navController.view];

    self.navigationController.navigationBarHidden = YES;

    UIBarButtonItem *leftButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAction target:self action:@selector(selectLeftAction:)];

    leftButton.title = @"123";

    rootView.navigationItem.leftBarButtonItem = leftButton;

    UIBarButtonItem *rightButton = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemAdd  target:self action:@selector(selectRightAction:)];

    rootView.navigationItem.rightBarButtonItem = rightButton;

}

iOS navigationbar添加实现