private void OnInterstitialAdOpenedHandler()
{
DDNASmartAds.Instance.OnInterstitialAdOpened -= this.OnInterstitialAdOpenedHandler;
DDNASmartAds.Instance.OnInterstitialAdFailedToOpen -= this.OnInterstitialAdFailedToOpenHandler;
if (this.OnInterstitialAdOpened != null) {
this.OnInterstitialAdOpened();
}
}