[Register("MyView")]
public sealed class MyView : MvxViewController, IUIViewControllerTransitioningDelegate
{
    public MyView()
    {
        WeakTransitioningDelegate = this;
    }


    private static readonly CECrossfadeAnimationController CrossFadeAnimationController = new CECrossfadeAnimationController();

    [Export ("animationControllerForPresentedController:presentingController:sourceController:")]
    public IUIViewControllerAnimatedTransitioning PresentingController(UIViewController presented, UIViewController presenting, UIViewController source)
    {
        CrossFadeAnimationController.Reverse = false;
        return CrossFadeAnimationController;
    }


    [Export ("animationControllerForDismissedController:")]
    public IUIViewControllerAnimatedTransitioning GetAnimationControllerForDismissedController(UIViewController dismissed)
    {
        CrossFadeAnimationController.Reverse = true;
        return CrossFadeAnimationController;
    }
}

myNavigationController.PushViewController(viewController, true);