added in version 22.1.0




MediaButtonReceiver A media button receiver receives and helps translate hardware media playback buttons, such as those found on wired and wireless headsets, into the appropriate callbacks in your app. 
MediaControllerCompat Allows an app to interact with an ongoing media session. 
MediaControllerCompat.Callback Callback for receiving updates on from the session. 
MediaControllerCompat.PlaybackInfo Holds information about the way volume is handled for this session. 
MediaControllerCompat.TransportControls Interface for controlling media playback on a session. 
MediaSessionCompat Allows interaction with media controllers, volume keys, media buttons, and transport controls. 
MediaSessionCompat.Callback Receives transport controls, media buttons, and commands from controllers and the system. 
MediaSessionCompat.QueueItem A single item that is part of the play queue. 
MediaSessionCompat.Token Represents an ongoing session. 
ParcelableVolumeInfo Convenience class for passing information about the audio configuration of a MediaSessionCompat
PlaybackStateCompat Playback state for a MediaSessionCompat
PlaybackStateCompat.Builder Builder for PlaybackStateCompat objects. 
PlaybackStateCompat.CustomAction CustomActions can be used to extend the capabilities of the standard transport controls by exposing app specific actions to Controllers
PlaybackStateCompat.CustomAction.Builder Builder for PlaybackStateCompat.CustomAction objects.