I am trying to present a `UINavigationController` modally from a `UIViewController`. From previous experience, I'm pretty sure that when I do this there should be a cancel button by default in the navigation bar, however with the following code the navigation bar is completely blank. Any ideas?

```
UIViewController *rootVC = [[UIViewController alloc] init];
UINavigationController *navController = [[UINavigationController alloc] initWithRootViewController:rootVC];
[self presentViewController:navController animated:YES completion:nil];

```