private static extern void GADUSetCallbacks( IntPtr bannerView, GADUAdViewDidReceiveAdCallback adReceivedCallback, GADUAdViewDidFailToReceiveAdWithErrorCallback adFailedCallback, GADUAdViewWillPresentScreenCallback willPresentCallback, GADUAdViewWillDismissScreenCallback willDismissCallback, GADUAdViewDidDismissScreenCallback didDismissCallback, GADUAdViewWillLeaveApplicationCallback willLeaveCallback);