Applications are expected to have a root view controller at the end of application launch

Question

I get the following error in my console:

Applications are expected to have a root view controller at the end of application launch

Answer 1

None of the above suggestions solved my problem. Mine was this:

Add:

window.rootViewController = navigationController;

after:

[window addSubview:navigationController.view];

in my appdelegate's

- (void)applicationDidFinishLaunching:(UIApplication *)application {

Answer 2

i got this problems too. i got my project run in xcode4.2.1. i've read all comments up there, but no one is cool for me. after a while, i find that i commented a piece of code.

//self.window = [[[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]] autorelease];

then i uncommented it. everything is ok for me. hope this would helpful for you guys.

Answer 3

Make sure you have this function in your application delegate.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:    (NSDictionary *)launchOptions {
   return YES;
}

Make sure didFinishLaunchingWithOptions returns YES. If you happened to remove the 'return YES' line, this will cause the error. This error may be especially common with storyboard users.

Answer 4

If you use MTStatusBarOverlay, then you'll get this error.

MTStatusBarOverlay creates an additional window ([[UIApplication sharedApplication] windows) which doesn't have a root controller.

This doesn't seem to cause a problem.

Answer 5

OrdoDei gave a correct and valuable answer. I'm adding this answer only to give an example of a didFinishLaunchingWithOptions method that uses his answer as well as accounting for the others’ comments regarding Navigation Controller.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    // Override point for customization after application launch.

    // Instantiate the main menu view controller (UITableView with menu items).
    // Pass that view controller to the nav controller as the root of the nav stack.
    // This nav stack drives our *entire* app.
    UIViewController *viewController = [[XMMainMenuTableViewController alloc] init];
    self.navigationController = [[UINavigationController alloc] initWithRootViewController:viewController];

    // Instantiate the app's window. Then get the nav controller's view into that window, and onto the screen.
    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
    // [self.window addSubview:self.navigationController.view];
    // The disabled line above was replaced by line below. Fixed Apple's complaint in log: Application windows are expected to have a root view controller at the end of application launch
    [self.window setRootViewController:self.navigationController];
    self.window.backgroundColor = [UIColor whiteColor];
    [self.window makeKeyAndVisible];
    return YES;
}

Answer 6

Replace in AppDelegate

 [window addSubview:[someController view]];

to

  [self.window setRootViewController:someController];