Ad callbacks

[SAVideoAd setCallback:^(NSInteger placementId, SAEvent event) {
    switch (event) {
        case adLoaded: {
            // called when an ad has finished loading
            break;
        }
        case adEmpty: {
            // called when the request was successful but the ad server returned no ad
            break;
        }
        case adFailedToLoad: {
            // called when an ad could not be loaded
            break;
        }
        case adShown: {
            // called when an ad is first shown
            break;
        }
        case adFailedToShow: {
            // called when an ad fails to show
            break;
        }
        case adClicked: {
            // called when an ad is clicked
            break;
        }
        case adEnded: {
            // called when a video ad has ended playing (but hasn't yet closed)
            break;
        }
        case adClosed: {
            // called when a fullscreen ad is closed
            break;
        }
    }
}];