Modal segue class

ModalSegue.h

@interface ModalSegue : UIStoryboardSegue

@property(nonatomic, readonly) UINavigationController *navigationController;

@end

ModalSegue.m

@implementation ModalSegue

- (instancetype)initWithIdentifier:(NSString *)identifier
                            source:(UIViewController *)source
                       destination:(UIViewController *)destination {
  
  if (self = [super initWithIdentifier:identifier source:source destination:destination]) {
    // Package the destination VC up into a nav controller
    _navigationController = [[UINavigationController alloc] initWithRootViewController:destination];
    _navigationController.modalPresentationStyle = destination.modalPresentationStyle;
  }
  return self;
}

- (void)perform {
  // Present the navigation controller, rather than presenting the destination VC directly
  [self.sourceViewController presentViewController:self.navigationController
                                          animated:YES
                                        completion:NULL];
}

@end