How to choose which Storyboard loads - ios

Question

I need to choose which MainViewController.h to load depending on the iPhone model that the app is running on. Using the code below, I distinguish between iPhone 4/4S and 5/5S/5C. Because of the auto layout, I will need to create two mainViewController.hs and then choose depending on the model of the phone. How do I do this? This is the code I have:
#define IS_IPHONE_5 ( fabs( ( double )[ [ UIScreen mainScreen ] bounds ].size.height - ( double )568 ) < DBL_EPSILON )
- (void)viewDidLoad
{
[super viewDidLoad];
if (IS_IPHONE_5) {
NSLog(#"Iphone 5");
} else {
NSLog(#"Iphone4");
}
}
So please tell me how to chose MainViewController.h.
AppDelegate.m:
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
[application registerForRemoteNotificationTypes:UIRemoteNotificationTypeBadge|
UIRemoteNotificationTypeAlert|
UIRemoteNotificationTypeSound];
// Override point for customization after application launch.
return YES;
UIStoryboard *storyboard;
CGSize screenSize = [[UIScreen mainScreen] bounds].size;
if (screenSize.height == 568) {
// iPhone 5
storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPhone5" bundle:nil];
} else {
// iPhone 4
storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPhone4" bundle:nil];
}
UIViewController *initialViewController = [storyboard instantiateInitialViewController];
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
self.window.rootViewController = initialViewController;
[self.window makeKeyAndVisible];
}

Answer 1

To specify which storyboard to load, do so in your AppDelegate's application:didFinishLaunchingWithOptions: method.
Load the storyboard that corresponds to the screen size using its storyboard name, ex:
UIStoryboard *storyboard;
CGSize screenSize = [[UIScreen mainScreen] bounds].size;
if (screenSize.height == 568) {
// iPhone 5, i.e. 568 pixels high
storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPhone5" bundle:nil];
} else {
// earlier model iPhones, i.e. 480 pixels high
storyboard = [UIStoryboard storyboardWithName:#"MainStoryboard_iPhone4" bundle:nil];
}
UIViewController *initialViewController = [storyboard instantiateInitialViewController];
self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
self.window.rootViewController = initialViewController;
[self.window makeKeyAndVisible];