iOS导航栏跳转

iOS中当注册的根视图中的导航栏还不存在的时候，想要用导航栏跳转 

RegristerChooseController * rgc=[UIStoryboardViewControllerInStoryBoard:@"RegristerChooseController"withIdentified:@"RegristerChooseController"];

    rgc.hidesBottomBarWhenPushed=YES;

    UINavigationController *nv =[[UINavigationControlleralloc] initWithRootViewController:rgc];

    [selfpresentViewController:nv animated:YEScompletion:nil];

    [self.navigationControllerpushViewController:rgc animated:YES];