All FvVideoDocument listeners must implement this interface.
public function onMetaData(event:FvReaderEvent):VoidInits UI with passed-in FvVideoDocument video document.
public function onVideoPlayHeadChange(event:FvReaderEvent):VoidUpdate progression bar with current time
public function onErrorDocument(event:FvReaderEvent):VoidTriggered when an error occured during video loading process.
Thus video is not available, hides the control bar.
public function onVideoPlayChange(event:FvReaderEvent):VoidTriggered when user change "play/pause" state of video.
public function onVideoMute(event:FvReaderEvent):VoidTriggered when user change "mute" state of video.