Create Navigationcontroller in View based application

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

    self.viewController = [[[ViewController alloc] initWithNibName:@"ViewController" bundle:nil] autorelease];

    self.Nav=[[UINavigationController alloc] initWithRootViewController:self.viewController];

    

    [self.window setRootViewController:_Nav];

    

    [self.window makeKeyAndVisible];

    return YES;