void ShowBannerAd(UIAlertAction obj) { bannerAdView?.RemoveFromSuperview(); bannerAdView?.Dispose(); bannerAdView = null; bannerAdView = new AdView(AdPlacementIds.Banner, AdSizes.BannerHeight50, this) { Delegate = this }; bannerAdView.Frame = new CGRect(0, 0, bannerAdView.Bounds.Width, bannerAdView.Bounds.Height); bannerAdView.LoadAd(); BannerView.AddSubview(bannerAdView); }