Xcode 7: Applications are expected to have a root view controller at the end of application launch

[MavEtJu]

--- a/BHTabBarDemo/BHTabBarDemo/BHTabBarDemoAppDelegate.m
+++ b/BHTabBarDemo/BHTabBarDemo/BHTabBarDemoAppDelegate.m    
@@ -20,7 +20,7 @@
   iv.frame = self.window.frame;
   [self.window addSubview:iv];

-  [self.window addSubview:viewController.view];
+  [self.window setRootViewController:viewController];
   [self.window makeKeyAndVisible];

   return YES;