@protocol JWLevelsEvent <NSObject>
JWLevelsEvent is emitted when the qualify levels or audio tracks information are available.
The full array of quality levels in the case of onLevels. The full array of audio tracks in the case of onAudioTracks. Returns nil in the case of an HLS stream.
@property (nonatomic, assign, unsafe_unretained, readwrite) NSArray *_Nonnull levels;