MediaSessionCompat

Kotlin |Java

open class MediaSessionCompat

kotlin.Any
↳	android.support.v4.media.session.MediaSessionCompat

Allows interaction with media controllers, volume keys, media buttons, and transport controls.

A MediaSession should be created when an app wants to publish media playback information or handle media keys. In general an app only needs one session for all playback, though multiple sessions can be created to provide finer grain controls of media.

Once a session is created the owner of the session may pass its session token to other processes to allow them to create a MediaControllerCompat to interact with the session.

To receive commands, media keys, and other events a Callback must be set with setCallback(Callback).

When an app is finished performing playback it must call release() to clean up the session and notify any controllers.

MediaSessionCompat objects are not thread safe and all calls should be made from the same thread.

This is a helper for accessing features in android.media.session.MediaSession introduced after API level 4 in a backwards compatible fashion.

Developer Guides

For information about building your media application, read the Media Apps developer guide.

Summary

Nested classes
abstract	Callback Receives transport controls, media buttons, and commands from controllers and the system.
abstract	OnActiveChangeListener
	QueueItem A single item that is part of the play queue.
	Token Represents an ongoing session.

Constants
static String	ACTION_FLAG_AS_INAPPROPRIATE Predefined custom action to flag the media that is currently playing as inappropriate.
static String	ACTION_FOLLOW Predefined custom action to follow an artist, album, or playlist.
static String	ACTION_SKIP_AD Predefined custom action to skip the advertisement that is currently playing.
static String	ACTION_UNFOLLOW Predefined custom action to unfollow an artist, album, or playlist.
static String	ARGUMENT_MEDIA_ATTRIBUTE Argument to indicate the media attribute.
static String	ARGUMENT_MEDIA_ATTRIBUTE_VALUE String argument to indicate the value of the media attribute (e.g., the name of the artist).
static Int	FLAG_HANDLES_MEDIA_BUTTONS Sets this flag on the session to indicate that it can handle media button events.
static Int	FLAG_HANDLES_QUEUE_COMMANDS Sets this flag on the session to indicate that it handles queue management commands through its Callback.
static Int	FLAG_HANDLES_TRANSPORT_CONTROLS Sets this flag on the session to indicate that it handles transport control commands through its Callback.
static Int	MEDIA_ATTRIBUTE_ALBUM The value of ARGUMENT_MEDIA_ATTRIBUTE indicating the album.
static Int	MEDIA_ATTRIBUTE_ARTIST The value of ARGUMENT_MEDIA_ATTRIBUTE indicating the artist.
static Int	MEDIA_ATTRIBUTE_PLAYLIST The value of ARGUMENT_MEDIA_ATTRIBUTE indicating the playlist.

Public constructors
<init>(@NonNull context: Context, @NonNull tag: String) Creates a new session.
<init>(@NonNull context: Context, @NonNull tag: String, @Nullable mbrComponent: ComponentName?, @Nullable mbrIntent: PendingIntent?) Creates a new session with a specified media button receiver (a component name and/or a pending intent).

Public methods
open Unit	addOnActiveChangeListener(listener: MediaSessionCompat.OnActiveChangeListener!) Adds a listener to be notified when the active status of this session changes.
open static MediaSessionCompat!	fromMediaSession(context: Context!, mediaSession: Any!) Creates an instance from a framework android.media.session.MediaSession object.
open MediaControllerCompat!	getController() Gets a controller for this session.
MediaSessionManager.RemoteUserInfo	getCurrentControllerInfo() Gets the controller information who sent the current request.
open Any!	getMediaSession() Gets the underlying framework android.media.session.MediaSession object.
open Any!	getRemoteControlClient() Gets the underlying framework android.media.RemoteControlClient object.
open MediaSessionCompat.Token!	getSessionToken() Retrieves a token object that can be used by apps to create a MediaControllerCompat for interacting with this session.
open Boolean	isActive() Gets the current active state of this session.
open Unit	release() This must be called when an app has finished performing playback.
open Unit	removeOnActiveChangeListener(listener: MediaSessionCompat.OnActiveChangeListener!) Stops the listener from being notified when the active status of this session changes.
open Unit	sendSessionEvent(event: String!, extras: Bundle!) Sends a proprietary event to all MediaControllers listening to this Session.
open Unit	setActive(active: Boolean) Sets if this session is currently active and ready to receive commands.
open Unit	setCallback(callback: MediaSessionCompat.Callback!) Adds a callback to receive updates on for the MediaSession.
open Unit	setCallback(callback: MediaSessionCompat.Callback!, handler: Handler!) Sets the callback to receive updates for the MediaSession.
open Unit	setCaptioningEnabled(enabled: Boolean) Enables/disables captioning for this session.
open Unit	setExtras(extras: Bundle!) Sets some extras that can be associated with the MediaSessionCompat.
open Unit	setFlags(flags: Int) Sets any flags for the session.
open Unit	setMediaButtonReceiver(mbr: PendingIntent!) Sets a pending intent for your media button receiver to allow restarting playback after the session has been stopped.
open Unit	setMetadata(metadata: MediaMetadataCompat!) Updates the current metadata.
open Unit	setPlaybackState(state: PlaybackStateCompat!) Updates the current playback state.
open Unit	setPlaybackToLocal(stream: Int) Sets the stream this session is playing on.
open Unit	setPlaybackToRemote(volumeProvider: VolumeProviderCompat!) Configures this session to use remote volume handling.
open Unit	setQueue(queue: MutableList<MediaSessionCompat.QueueItem!>!) Updates the list of items in the play queue.
open Unit	setQueueTitle(title: CharSequence!) Sets the title of the play queue.
open Unit	setRatingType(type: Int) Sets the style of rating used by this session.
open Unit	setRepeatMode(repeatMode: Int) Sets the repeat mode for this session.
open Unit	setSessionActivity(pi: PendingIntent!) Sets an intent for launching UI for this Session.
open Unit	setShuffleMode(shuffleMode: Int) Sets the shuffle mode for this session.

Constants

ACTION_FLAG_AS_INAPPROPRIATE

static val ACTION_FLAG_AS_INAPPROPRIATE: String

Predefined custom action to flag the media that is currently playing as inappropriate.

Value: "android.support.v4.media.session.action.FLAG_AS_INAPPROPRIATE"

See Also

• Callback#onCustomAction

ACTION_FOLLOW

static val ACTION_FOLLOW: String

Predefined custom action to follow an artist, album, or playlist. The extra bundle must have ARGUMENT_MEDIA_ATTRIBUTE to indicate the type of the follow action. The bundle can also have an optional string argument, ARGUMENT_MEDIA_ATTRIBUTE_VALUE, to specify the target to follow (e.g., the name of the artist to follow). If this argument is omitted, the currently playing media will be the target of the action. Thus, the session must perform the follow action with the current metadata. If there's no specified attribute in the current metadata, the controller must not omit this argument.

Value: "android.support.v4.media.session.action.FOLLOW"

See Also

• #ARGUMENT_MEDIA_ATTRIBUTE#ARGUMENT_MEDIA_ATTRIBUTE_VALUECallback#onCustomAction

ACTION_SKIP_AD

static val ACTION_SKIP_AD: String

Predefined custom action to skip the advertisement that is currently playing.

Value: "android.support.v4.media.session.action.SKIP_AD"

See Also

• Callback#onCustomAction

ACTION_UNFOLLOW

static val ACTION_UNFOLLOW: String

Predefined custom action to unfollow an artist, album, or playlist. The extra bundle must have ARGUMENT_MEDIA_ATTRIBUTE to indicate the type of the unfollow action. The bundle can also have an optional string argument, ARGUMENT_MEDIA_ATTRIBUTE_VALUE, to specify the target to unfollow (e.g., the name of the artist to unfollow). If this argument is omitted, the currently playing media will be the target of the action. Thus, the session must perform the unfollow action with the current metadata. If there's no specified attribute in the current metadata, the controller must not omit this argument.

Value: "android.support.v4.media.session.action.UNFOLLOW"

See Also

• #ARGUMENT_MEDIA_ATTRIBUTE#ARGUMENT_MEDIA_ATTRIBUTE_VALUECallback#onCustomAction

ARGUMENT_MEDIA_ATTRIBUTE

static val ARGUMENT_MEDIA_ATTRIBUTE: String

Argument to indicate the media attribute. It should be one of the following:

• MEDIA_ATTRIBUTE_ARTIST
• MEDIA_ATTRIBUTE_PLAYLIST
• MEDIA_ATTRIBUTE_ALBUM

Value: "android.support.v4.media.session.ARGUMENT_MEDIA_ATTRIBUTE"

ARGUMENT_MEDIA_ATTRIBUTE_VALUE

static val ARGUMENT_MEDIA_ATTRIBUTE_VALUE: String

String argument to indicate the value of the media attribute (e.g., the name of the artist).

Value: "android.support.v4.media.session.ARGUMENT_MEDIA_ATTRIBUTE_VALUE"

FLAG_HANDLES_MEDIA_BUTTONS

static val FLAG_HANDLES_MEDIA_BUTTONS: Int

Deprecated: This flag is no longer used. All media sessions are expected to handle media button events now. For backward compatibility, this flag will be always set.

Sets this flag on the session to indicate that it can handle media button events.

Value: 1 << 0

FLAG_HANDLES_QUEUE_COMMANDS

static val FLAG_HANDLES_QUEUE_COMMANDS: Int

Sets this flag on the session to indicate that it handles queue management commands through its Callback.

Value: 1 << 2

FLAG_HANDLES_TRANSPORT_CONTROLS

static val FLAG_HANDLES_TRANSPORT_CONTROLS: Int

Deprecated: This flag is no longer used. All media sessions are expected to handle transport controls now. For backward compatibility, this flag will be always set.

Sets this flag on the session to indicate that it handles transport control commands through its Callback.

Value: 1 << 1

MEDIA_ATTRIBUTE_ALBUM

static val MEDIA_ATTRIBUTE_ALBUM: Int

The value of ARGUMENT_MEDIA_ATTRIBUTE indicating the album.

Value: 1

See Also

• #ARGUMENT_MEDIA_ATTRIBUTE

MEDIA_ATTRIBUTE_ARTIST

static val MEDIA_ATTRIBUTE_ARTIST: Int

The value of ARGUMENT_MEDIA_ATTRIBUTE indicating the artist.

Value: 0

See Also

• #ARGUMENT_MEDIA_ATTRIBUTE

MEDIA_ATTRIBUTE_PLAYLIST

static val MEDIA_ATTRIBUTE_PLAYLIST: Int

The value of ARGUMENT_MEDIA_ATTRIBUTE indicating the playlist.

Value: 2

See Also

• #ARGUMENT_MEDIA_ATTRIBUTE

Public constructors

<init>

MediaSessionCompat(@NonNull context: Context, @NonNull tag: String)

Creates a new session. You must call release() when finished with the session.

The session will automatically be registered with the system but will not be published until setActive(true) is called.

For API 20 or earlier, note that a media button receiver is required for handling Intent#ACTION_MEDIA_BUTTON. This constructor will attempt to find an appropriate BroadcastReceiver from your manifest. See MediaButtonReceiver for more details.

Parameters
context	Context: The context to use to create the session.
tag	Context: A short name for debugging purposes.

<init>

MediaSessionCompat(@NonNull context: Context, @NonNull tag: String, @Nullable mbrComponent: ComponentName?, @Nullable mbrIntent: PendingIntent?)

Creates a new session with a specified media button receiver (a component name and/or a pending intent). You must call release() when finished with the session.

The session will automatically be registered with the system but will not be published until setActive(true) is called.

For API 20 or earlier, note that a media button receiver is required for handling Intent#ACTION_MEDIA_BUTTON. This constructor will attempt to find an appropriate BroadcastReceiver from your manifest if it's not specified. See MediaButtonReceiver for more details.

Parameters
context	Context: The context to use to create the session.
tag	Context: A short name for debugging purposes.
mbrComponent	Context: The component name for your media button receiver.
mbrIntent	Context: The PendingIntent for your receiver component that handles media button events. This is optional and will be used on between android.os.Build.VERSION_CODES#JELLY_BEAN_MR2 and android.os.Build.VERSION_CODES#KITKAT_WATCH instead of the component name.

Public methods

addOnActiveChangeListener

open fun addOnActiveChangeListener(listener: MediaSessionCompat.OnActiveChangeListener!): Unit

Adds a listener to be notified when the active status of this session changes. This is primarily used by the support library and should not be needed by apps.

Parameters
listener	MediaSessionCompat.OnActiveChangeListener!: The listener to add.

fromMediaSession

open static fun fromMediaSession(context: Context!, mediaSession: Any!): MediaSessionCompat!

Creates an instance from a framework android.media.session.MediaSession object.

This method is only supported on API 21+. On API 20 and below, it returns null.

Note: A MediaSessionCompat object returned from this method may not provide the full functionality of MediaSessionCompat until setting a new MediaSessionCompat.Callback. To avoid this, when both a MediaSessionCompat and a framework android.media.session.MediaSession are needed, it is recommended to create a MediaSessionCompat first and get the framework session through getMediaSession().

Parameters
context	Context!: The context to use to create the session.
mediaSession	Context!: A android.media.session.MediaSession object.

Return
MediaSessionCompat!: An equivalent MediaSessionCompat object, or null if none.

getController

open fun getController(): MediaControllerCompat!

Gets a controller for this session. This is a convenience method to avoid having to cache your own controller in process.

Return
MediaControllerCompat!: A controller for this session.

getCurrentControllerInfo

@NonNull fun getCurrentControllerInfo(): MediaSessionManager.RemoteUserInfo

Gets the controller information who sent the current request.

Note: This is only valid while in a request callback, such as Callback#onPlay.

Note: From API 21 to 23, this method returns a dummy RemoteUserInfo which has following values:

• Package name is MediaSessionManager.RemoteUserInfo#LEGACY_CONTROLLER.
• PID and UID will have negative values.

Note: From API 24 to 27, the RemoteUserInfo returned from this method will have negative uid and pid. Most of the cases it will have the correct package name, but sometimes it will fail to get the right one.

See Also

• MediaSessionManager.RemoteUserInfo#LEGACY_CONTROLLERMediaSessionManager#isTrustedForMediaControl(RemoteUserInfo)

getMediaSession

open fun getMediaSession(): Any!

Gets the underlying framework android.media.session.MediaSession object.

This method is only supported on API 21+.

Return
Any!: The underlying android.media.session.MediaSession object, or null if none.

getRemoteControlClient

open fun getRemoteControlClient(): Any!

Gets the underlying framework android.media.RemoteControlClient object.

This method is only supported on APIs 14-20. On API 21+ getMediaSession() should be used instead.

Return
Any!: The underlying android.media.RemoteControlClient object, or null if none.

getSessionToken

open fun getSessionToken(): MediaSessionCompat.Token!

Retrieves a token object that can be used by apps to create a MediaControllerCompat for interacting with this session. The owner of the session is responsible for deciding how to distribute these tokens.

On platform versions before android.os.Build.VERSION_CODES#LOLLIPOP this token may only be used within your app as there is no way to guarantee other apps are using the same version of the support library.

Return
MediaSessionCompat.Token!: A token that can be used to create a media controller for this session.

isActive

open fun isActive(): Boolean

Gets the current active state of this session.

Return
Boolean: True if the session is active, false otherwise.

release

open fun release(): Unit

This must be called when an app has finished performing playback. If playback is expected to start again shortly the session can be left open, but it must be released if your activity or service is being destroyed.

removeOnActiveChangeListener

open fun removeOnActiveChangeListener(listener: MediaSessionCompat.OnActiveChangeListener!): Unit

Stops the listener from being notified when the active status of this session changes.

Parameters
listener	MediaSessionCompat.OnActiveChangeListener!: The listener to remove.

sendSessionEvent

open fun sendSessionEvent(event: String!, extras: Bundle!): Unit

Sends a proprietary event to all MediaControllers listening to this Session. It's up to the Controller/Session owner to determine the meaning of any events.

Parameters
event	String!: The name of the event to send
extras	String!: Any extras included with the event

setActive

open fun setActive(active: Boolean): Unit

Sets if this session is currently active and ready to receive commands. If set to false your session's controller may not be discoverable. You must set the session to active before it can start receiving media button events or transport commands.

On platforms earlier than android.os.Build.VERSION_CODES#LOLLIPOP, a media button event receiver should be set via the constructor to receive media button events.

Parameters
active	Boolean: Whether this session is active or not.

setCallback

open fun setCallback(callback: MediaSessionCompat.Callback!): Unit

Adds a callback to receive updates on for the MediaSession. This includes media button and volume events. The caller's thread will be used to post events.

Parameters
callback	MediaSessionCompat.Callback!: The callback object

setCallback

open fun setCallback(callback: MediaSessionCompat.Callback!, handler: Handler!): Unit

Sets the callback to receive updates for the MediaSession. This includes media button and volume events. Set the callback to null to stop receiving events.

Parameters
callback	MediaSessionCompat.Callback!: The callback to receive updates on.
handler	MediaSessionCompat.Callback!: The handler that events should be posted on.

setCaptioningEnabled

open fun setCaptioningEnabled(enabled: Boolean): Unit

Enables/disables captioning for this session.

Parameters
enabled	Boolean: true to enable captioning, false to disable.

setExtras

open fun setExtras(extras: Bundle!): Unit

Sets some extras that can be associated with the MediaSessionCompat. No assumptions should be made as to how a MediaControllerCompat will handle these extras. Keys should be fully qualified (e.g. com.example.MY_EXTRA) to avoid conflicts.

Parameters
extras	Bundle!: The extras associated with the session.

setFlags

open fun setFlags(flags: Int): Unit

Sets any flags for the session.

Parameters
flags	Int: The flags to set for this session.

setMediaButtonReceiver

open fun setMediaButtonReceiver(mbr: PendingIntent!): Unit

Sets a pending intent for your media button receiver to allow restarting playback after the session has been stopped. If your app is started in this way an Intent#ACTION_MEDIA_BUTTON intent will be sent via the pending intent.

This method will only work on android.os.Build.VERSION_CODES#LOLLIPOP and later. Earlier platform versions must include the media button receiver in the constructor.

Parameters
mbr	PendingIntent!: The PendingIntent to send the media button event to.

setMetadata

open fun setMetadata(metadata: MediaMetadataCompat!): Unit

Updates the current metadata. New metadata can be created using android.support.v4.media.MediaMetadataCompat.Builder. This operation may take time proportional to the size of the bitmap to replace large bitmaps with a scaled down copy.

Parameters
metadata	MediaMetadataCompat!: The new metadata

See Also

• android.support.v4.media.MediaMetadataCompat.Builder#putBitmap

setPlaybackState

open fun setPlaybackState(state: PlaybackStateCompat!): Unit

Updates the current playback state.

Parameters
state	PlaybackStateCompat!: The current state of playback

setPlaybackToLocal

open fun setPlaybackToLocal(stream: Int): Unit

Sets the stream this session is playing on. This will affect the system's volume handling for this session. If setPlaybackToRemote was previously called it will stop receiving volume commands and the system will begin sending volume changes to the appropriate stream.

By default sessions are on AudioManager#STREAM_MUSIC.

Parameters
stream	Int: The AudioManager stream this session is playing on.

setPlaybackToRemote

open fun setPlaybackToRemote(volumeProvider: VolumeProviderCompat!): Unit

Configures this session to use remote volume handling. This must be called to receive volume button events, otherwise the system will adjust the current stream volume for this session. If setPlaybackToLocal was previously called that stream will stop receiving volume changes for this session.

On platforms earlier than android.os.Build.VERSION_CODES#LOLLIPOP this will only allow an app to handle volume commands sent directly to the session by a MediaControllerCompat. System routing of volume keys will not use the volume provider.

Parameters
volumeProvider	VolumeProviderCompat!: The provider that will handle volume changes. May not be null.

setQueue

open fun setQueue(queue: MutableList<MediaSessionCompat.QueueItem!>!): Unit

Updates the list of items in the play queue. It is an ordered list and should contain the current item, and previous or upcoming items if they exist. Specify null if there is no current play queue.

The queue should be of reasonable size. If the play queue is unbounded within your app, it is better to send a reasonable amount in a sliding window instead.

Parameters
queue	MutableList<MediaSessionCompat.QueueItem!>!: A list of items in the play queue.

setQueueTitle

open fun setQueueTitle(title: CharSequence!): Unit

Sets the title of the play queue. The UI should display this title along with the play queue itself. e.g. "Play Queue", "Now Playing", or an album name.

Parameters
title	CharSequence!: The title of the play queue.

setRatingType

open fun setRatingType(type: Int): Unit

Sets the style of rating used by this session. Apps trying to set the rating should use this style. Must be one of the following:

• RatingCompat#RATING_NONE
• RatingCompat#RATING_3_STARS
• RatingCompat#RATING_4_STARS
• RatingCompat#RATING_5_STARS
• RatingCompat#RATING_HEART
• RatingCompat#RATING_PERCENTAGE
• RatingCompat#RATING_THUMB_UP_DOWN

setRepeatMode

open fun setRepeatMode(repeatMode: Int): Unit

Sets the repeat mode for this session.

Note that if this method is not called before, MediaControllerCompat#getRepeatMode will return PlaybackStateCompat#REPEAT_MODE_NONE.

Parameters
repeatMode	Int: The repeat mode. Must be one of the followings: PlaybackStateCompat#REPEAT_MODE_NONE, PlaybackStateCompat#REPEAT_MODE_ONE, PlaybackStateCompat#REPEAT_MODE_ALL, PlaybackStateCompat#REPEAT_MODE_GROUP

setSessionActivity

open fun setSessionActivity(pi: PendingIntent!): Unit

Sets an intent for launching UI for this Session. This can be used as a quick link to an ongoing media screen. The intent should be for an activity that may be started using Activity#startActivity(Intent).

Parameters
pi	PendingIntent!: The intent to launch to show UI for this Session.

setShuffleMode

open fun setShuffleMode(shuffleMode: Int): Unit

Sets the shuffle mode for this session.

Note that if this method is not called before, MediaControllerCompat#getShuffleMode will return PlaybackStateCompat#SHUFFLE_MODE_NONE.

Parameters
shuffleMode	Int: The shuffle mode. Must be one of the followings: PlaybackStateCompat#SHUFFLE_MODE_NONE, PlaybackStateCompat#SHUFFLE_MODE_ALL, PlaybackStateCompat#SHUFFLE_MODE_GROUP