AVPlayerViewController.PrepareForPrerollAds Method      
Definition
Important
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Notify iAd that the application will use PlayPrerollAd, preloading ad information.
public static void PrepareForPrerollAds();static member PrepareForPrerollAds : unit -> unitRemarks
You should call this to give iAd a chance to prefecth information required to play an ad, this will increase the chances that an ad will be available when it is requested.