title: "Unrecognized selector sent to instance" after casting rootViewController to UINavigationController *
body: <p>Not too sure how to debug this. </p>
  
  <blockquote>
    <p>2013-01-24 20:36:18.448 SlideMenu[2069:c07] *** Terminating app due to uncaught exception     'NSInvalidArgumentException', reason: '-[initViewController viewControllers]: unrecognized selector sent to instance 0xac6cdb0'</p>
  </blockquote>
  
  <p>Here's initViewController.m</p>
  
  <pre><code>#import "initViewController.h"
  #import "ECSlidingViewController.h"
  #import "MenuViewController.h"
  
  @interface initViewController ()
  
  @end
  
  @implementation initViewController
  
  - (void)viewDidLoad
  {
      [super viewDidLoad];
      self.topViewController = [self.storyboard instantiateViewControllerWithIdentifier:@"Main"];
  }
  
  @end
  </code></pre>
  
  <p>And where the exception is being thrown:</p>
  
  <p>AppDelegate.m</p>
  
  <pre><code>#import "AppDelegate.h"
  #import "MainViewController.h"
  #import "ListDoc.h"
  
  @implementation AppDelegate
  
  - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
  {
      ListDoc *list1 = [[ListDoc alloc] initWithTitle:@"Potato Bug" thumbImage:[UIImage imageNamed:@"potatoBugThumb.jpg"]];
      ListDoc *list2 = [[ListDoc alloc] initWithTitle:@"House Centipede" thumbImage:[UIImage imageNamed:@"centipedeThumb.jpg"]];
      NSMutableArray *lists = [NSMutableArray arrayWithObjects:list1,list2,nil];
  
      UINavigationController * navController = (UINavigationController *) self.window.rootViewController;
      MainViewController * mainController = [navController.viewControllers objectAtIndex:0];
      mainController.someData = lists;
      // Override point for customization after application launch.
      return YES;
  }
  
  @end
  </code></pre>