Question

When I Build my app, it compiles without any problems or errors. But when I run it I see this message in console:

Application windows are expected to have a root view controller at the end of application launch.

Here is my Appdelegate’s method which I believe might be causing this(based on other posts Ive seen on SO)

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions: (NSDictionary *)launchOptions

  self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
  // Override point for customization after application launch.
  self.window.backgroundColor = [UIColor whiteColor];


  PhotosViewController *viewController = [[PhotosViewController alloc] initWithNibName:nil bundle:nil];

  self.navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];
  [self.window addSubview:self.navigationController.view];

  [self.window makeKeyAndVisible];

   return YES;

Is this something that I need to be worried about? My app runs in the simulator even though this message shows up.

Any suggestions on what I should do to get rid of it? What can I do to debug this?

BTW, I have seen other questions on SO with the similar error message, however, none of the scenarios apply to mine so I have posted this question. Its not a duplicate 🙂

Thanks

Answer 1

Instead of:

[self.window addSubview:self.navigationController.view];

Use:

self.window.rootViewController = self.navigationController;

You can find more details in the UIWindow documentation