UIViewController

Subclassing

Create an instance

Swift

let viewController = UIViewController()

Objective-C

UIViewController *viewController = [UIViewController new];

Set the view programmatically

Swift

class FooViewController: UIViewController {

  override func loadView() {
    view = FooView()
  }

}

Instantiate from a Storyboard

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];

With an Identifier:

Give the scene a Storyboard ID within the identity inspector of the storyboard.

Instantiate in code:

UIViewController *controller = [storyboard instantiateViewControllerWithIdentifier:@"myIdentifier"];

Instantiate an initial viewcontroller:

Within the storyboard select the view controller, then select the attribute inspector, check the “Is Initial View Controller” box.

UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
UIViewController *controller = [storyboard instantiateInitialViewController];

Access the container view controller

When the view controller is presented within a tab bar controller, you can access the tab bar controller like this:

Swift

let tabBarController = viewController.tabBarController

Objective-C

UITabBarController *tabBarController = self.tabBarController;

When the view controller is part on an navigation stack, you can access the navigation controller like this:

Swift

let navigationController = viewController.navigationController

Objective-C

UINavigationController *navigationController = self.navigationController;

Adding/removing a child view controller

To add a child view controller:

- (void)displayContentController:(UIViewController *)vc {
   [self addChildViewController:vc];
   vc.view.frame = self.view.frame;
   [self.view addSubview:vc.view];
   [vc didMoveToParentViewController:self];
}

To remove a child view controller:

- (void)hideContentController:(UIViewController *)vc {
   [vc willMoveToParentViewController:nil];
   [vc.view removeFromSuperview];
   [vc removeFromParentViewController];
}