Push a VC onto UINavigationController with completion callback #ios #transitions #intermediate

uinavvc_push_with_callback.m

- (void)pushViewController:(UIViewController *)viewController
                  animated:(BOOL)animated
                completion:(void (^)(BOOL finished))completion
{
  [self pushViewController:viewController animated:animated];
  if (animated) {
    [self.transitionCoordinator
     animateAlongsideTransition:nil
     completion:^(id<UIViewControllerTransitionCoordinatorContext> context)
     {
       completion ? completion(![context isCancelled]) : nil;
     }];
  } else {
    completion ? completion(YES) : nil;
  }
}