[iOS] AirPlay second screen with UIViewController and Storyboard

#import "ViewController.h"
#import "SecondViewController.h"

@interface ViewController ()
@property UIWindow *extWindow;
@end

@implementation ViewController

- (void)viewDidLoad
{
    [super viewDidLoad];
	[[NSNotificationCenter defaultCenter] addObserver:self
											 selector:@selector(screenDidConnect:)
												 name:UIScreenDidConnectNotification
											   object:nil];

	[[NSNotificationCenter defaultCenter] addObserver:self
											 selector:@selector(screenDidDisconnect:)
												 name:UIScreenDidDisconnectNotification
											   object:nil];

	[self performSelector:@selector(checkScreenCount) withObject:nil afterDelay:0];
}

-(void) screenDidConnect:(NSNotification*)noti
{
	[self prepareScreen];
}

-(void) screenDidDisconnect:(NSNotification*)noti
{
	self.extWindow.hidden = YES;
}

-(void) checkScreenCount
{
	if ([UIScreen screens].count > 1)
		[self prepareScreen];
}

-(void)prepareScreen
{
	UIScreen* screen = [[UIScreen screens] objectAtIndex:1];

	CGRect frame = screen.bounds;
	self.extWindow = [[UIWindow alloc] initWithFrame:frame];
	self.extWindow.screen = screen;

	SecondViewController* secondViewCtrl = [self.storyboard instantiateViewControllerWithIdentifier:@"secondView"];
	self.extWindow.rootViewController = secondViewCtrl;

	self.extWindow.hidden = NO;
}
@end