View is only displaying for a fraction of a second

Question

I have a LoginViewController class that extends UIViewController that is only displaying for a fraction of a second. In my AppDelegate.m class I try to allocate a UINavigationController that will have LoginViewController as a child view controller. I see loginViewController's view for a split second before the view goes black (I see the view I designed in Interface Builder). I'm not really sure why this is occurring.

Aside from the view flashing quickly, I was running the app on a 2nd gen iPod touch and noticed I could swipe my thumb to the right and see apps from the home screen. One more swipe and I could see search, but icons at the bottom such as music, mail, safari, and videos were not visible. Pressing stop button killed the app and returned to a normal home screen. This makes me think I'm setting the root view controller incorrectly? I took the if respondsToSelector code from another question here on Stack Overflow. The if stopped my code from crashing which I think has something to do with devices older than iOS 4? When it ran without crashing is when I started receiving login view flashing just once and the home screen apps are just a thumb swipe away.

Any help is appreciated. If more of my code would help explain my question just let me know and I'll post more.

Edit: Forgot to post Xcode Version 4.4 and Deployment iOS targeted 4.0

AppDelegate.m:

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

    mainViewController = [[[MainViewController alloc] initWithNibName:@"MainViewController" bundle:nil] autorelease];
    loginViewController = [[[LoginViewController alloc] initWithNibName:@"LoginViewController" bundle:nil] autorelease];

    navigationController = [[UINavigationController alloc] init];
    [navigationController pushViewController:loginViewController animated:NO];
    if([window respondsToSelector:@selector(setRootViewController:)])
    {
        [window setRootViewController:navigationController];
    }
    else
    {
        [window addSubview:[navigationController view]];
    }

    initWithRootViewController:viewController] autorelease];
    initWithNibName:@"ContainerViewController" bundle:nil] autorelease];

    [window makeKeyAndVisible];
    return YES;
}

Answer 1

Take out the autorelease in your window-creating line. You want the window to live as long as the application is running.