void InitAdView()
{
adView.AdLoaded += delegate(object sender, EventArgs e) {
placeholderLabel.Hidden = true;
((ADBannerView)sender).Hidden = false;
};
adView.FailedToReceiveAd += delegate(object sender, AdErrorEventArgs e) {
((ADBannerView)sender).Hidden = true;
placeholderLabel.Hidden = false;
};
}