Limit orientation to one ViewController

Limit Orientation

// implement the following code in AppDelegate.m
// implement a dummy method "canRotate" in the ViewController that you want to rotate

#pragma mark - Rotation methods

-(NSUInteger)application:(UIApplication *)application supportedInterfaceOrientationsForWindow:(UIWindow *)window {
    
    // Get topmost/visible view controller
    UIViewController *currentViewController = [self topViewController];
    
    // Check whether it implements a dummy methods called canRotate
    if ([currentViewController respondsToSelector:@selector(canRotate)]) {
        // Unlock landscape view orientations for this view controller
        return UIInterfaceOrientationMaskAllButUpsideDown;
    }
    
    // Only allow portrait (standard behaviour)
    return UIInterfaceOrientationMaskPortrait;
}

-(UIViewController *)topViewController {
    return [self topViewControllerWithRootViewController:[UIApplication sharedApplication].keyWindow.rootViewController];
}

-(UIViewController *)topViewControllerWithRootViewController:(UIViewController *)rootViewController {
    
    if ([rootViewController isKindOfClass:[UITabBarController class]]) {
        UITabBarController* tabBarController = (UITabBarController*)rootViewController;
        return [self topViewControllerWithRootViewController:tabBarController.selectedViewController];
    }
    else if ([rootViewController isKindOfClass:[UINavigationController class]]) {
        UINavigationController* navigationController = (UINavigationController*)rootViewController;
        return [self topViewControllerWithRootViewController:navigationController.visibleViewController];
    }
    else if (rootViewController.presentedViewController) {
        UIViewController* presentedViewController = rootViewController.presentedViewController;
        return [self topViewControllerWithRootViewController:presentedViewController];
    }
    else if ([rootViewController isKindOfClass:[MMDrawerController class]]) {
        MMDrawerController *drawer = (MMDrawerController *)rootViewController;
        if (drawer.openSide == MMDrawerSideLeft) {
            return drawer.leftDrawerViewController;
        }
        else if (drawer.openSide == MMDrawerSideNone){
            return drawer.centerViewController;
        }
        else {
            return drawer.rightDrawerViewController;
        }
    }
    else {
        return rootViewController;
    }
}

-(void)canRotate {
    
}