UIWindow's root view controller does not rotate to landscape at app launch

Question

I am developing a xib-based landscape-only app. The app launches in landscape correctly. However, the view in my main ViewController is presented in portrait. That is, it is

Answer 1

I had this same issue: an app which was meant to be in Landscape that assumed the ViewController was always in Portrait. I made tons of changes to every aspect of the project and info.plist, including giving the main UIWindow a root-view controller which was landscape. It still didn't work. I eventually undid all the changes and just added the two lines noted below to my app delegate:

- (void)applicationDidFinishLaunching:(UIApplication *)application 
{
    [_window addSubview:[_viewController view]];
    glView = _viewController.glView;

    // THIS FIXED ORIENTATION FOR ME IN IOS 6
    _window.rootViewController = self.viewController;
    [self.window makeKeyAndVisible];
    // END

    ...my other setup code here...
}

Nothing else was necessary.

It appears that, for some reason, in iOS 6 the UIWindow root-view-controller setting is sometimes ignored in Interface Builder. I am sure my reasoning is wrong somewhere, but I thought this might well help prod someone in the direction of a fuller, more exhaustive answer.

Answer 2

In iOS 8, settings windows frame to the UIScreen is also necessary, as it won't get automatically updated.

self.window.frame = [UIScreen mainScreen].bounds;