Jetpack Media3 defines a Player interface that outlines basic functionality
for playback of video and audio files. ExoPlayer is the default implementation
of this interface in Media3. We recommend using ExoPlayer, as it provides a
comprehensive set of features that cover most playback use-cases and is
customizable to handle any additional use-cases you might have. ExoPlayer also
abstracts away device and OS fragmentation so your code works consistently
across the entire Android ecosystem. ExoPlayer includes:
- Support for playlists
- Support for a variety of progressive and adaptive streaming formats
- Support for both client-side and server-side ad insertion
- Support for DRM-protected playback
This page walks you through some of the key steps in building a playback app, and for more details you can head to our full guides on Media3 ExoPlayer.
Getting started
To get started, add a dependency on the ExoPlayer, UI, and Common modules of Jetpack Media3:
Kotlin
implementation("androidx.media3:media3-exoplayer:1.10.1")
implementation("androidx.media3:media3-ui:1.10.1")
implementation("androidx.media3:media3-common:1.10.1")
Groovy
implementation "androidx.media3:media3-exoplayer:1.10.1"
implementation "androidx.media3:media3-ui:1.10.1"
implementation "androidx.media3:media3-common:1.10.1"
Depending on your use-case, you may also need additional modules from Media3,
such as exoplayer-dash to play streams in the DASH format.
Make sure to replace 1.10.1 with your preferred version of the
library. You can refer to the release notes to see the latest
version.
Creating a media player
With Media3, you can either use the included implementation of the Player
interface, ExoPlayer, or you can build your own custom implementation.
Creating an ExoPlayer
The simplest way to create an ExoPlayer instance is as follows:
Kotlin
val player = ExoPlayer.Builder(context).build()
Java
ExoPlayer player = new ExoPlayer.Builder(context).build();
You can create your media player in the onCreate() lifecycle method of the
Activity, Fragment, or Service where it lives.
The Builder includes a range of customization options you may be interested
in, such as:
setAudioAttributes()to configure audio focus handlingsetHandleAudioBecomingNoisy()to configure playback behavior when an audio output device is disconnectedsetTrackSelector()to configure track selection
Media3 provides a PlayerView UI component that you can include in your app's
layout file. This component encapsulates a PlayerControlView for playback
controls, SubtitleView for displaying subtitles, and Surface for rendering
video.
Preparing the player
Add media items to a playlist for playback with methods like
setMediaItem() and addMediaItem(). Then, call prepare() to start
loading media and acquire the necessary resources.
You shouldn't perform these steps before the app is in the foreground. If your
player is in an Activity or Fragment, this means preparing the player in the
onStart() lifecycle method on API level 24 and higher or the onResume()
lifecycle method on API level 23 and below. For a player that's in a Service,
you can prepare it in onCreate(). Refer to the Exoplayer codelab for an
example of how to implement lifecycle methods.
Control the player
After the player has been prepared, you can control playback by calling methods on the player such as:
play()andpause()to start and pause playbackseekTo()to seek to a position within the current media itemseekToNextMediaItem()andseekToPreviousMediaItem()to navigate through the playlist
UI components such as the PlayerView or PlayerControlView will update
accordingly when bound to a player.
Release the player
Playback can require resources that are in limited supply, such as video
decoders, so it's important to call release() on your player to free up
resources when the player is no longer needed.
If your player is in an Activity or Fragment, release the player in the
onStop() lifecycle method on API level 24 and higher or the onPause() method
on API level 23 and below. For a player that's in a Service, you can release
it in onDestroy(). Refer to the Exoplayer codelab for an example of how
to implement lifecycle methods.
Managing playback with a media session
On Android, media sessions provide a standardized way to interact with a media player across process boundaries. Connecting a media session to your player allows you to advertise your media playback externally and to receive playback commands from external sources, for example to integrate with system media controls on mobile and large screen devices.
To use media sessions, add a dependency on the Media3 Session module:
Kotlin
implementation("androidx.media3:media3-session:1.10.1")
Groovy
implementation "androidx.media3:media3-session:1.10.1"
Create a media session
You can create a MediaSession after initializing a player as follows:
Kotlin
val player = ExoPlayer.Builder(context).build()
val mediaSession = MediaSession.Builder(context, player).build()
Java
ExoPlayer player = new ExoPlayer.Builder(context).build();
MediaSession mediaSession = new MediaSession.Builder(context, player).build();
Media3 automatically syncs the state of the Player with the state of the
MediaSession. This works with any Player implementation, including
ExoPlayer, CastPlayer, or a custom implementation.
Grant control to other clients
Client apps can implement a media controller to control playback of your media
session. To receive these requests, set a callback object when building your
MediaSession.
When a controller is about to connect to your media session, the onConnect()
method is called. You can use the provided ControllerInfo to decide whether
to accept or reject the request. See an example of this in the Media3
Session demo app.
Once connected, a controller can send playback commands to the session. The
session then delegates those commands down to the player. Playback and playlist
commands defined in the Player interface are automatically handled by the
session.
Other callback methods allow you to handle, for example, requests for custom
playback commands and modifying the playlist. These callbacks similarly
include a ControllerInfo object so you can determine access control on a
request-by-request basis.
Playing media in the background
To continue playing media when your app is not in the foreground, for example to
play music, audiobooks, or podcasts even when the user doesn't have your app
open, your Player and MediaSession should be encapsulated in a foreground
service. Media3 provides the MediaSessionService interface for this purpose.
Implementing a MediaSessionService
Create a class that extends MediaSessionService and instantiate your
MediaSession in the onCreate() lifecycle method.
Kotlin
class PlaybackService : MediaSessionService() {
private var mediaSession: MediaSession? = null
// Create your Player and MediaSession in the onCreate lifecycle event
override fun onCreate() {
super.onCreate()
val player = ExoPlayer.Builder(this).build()
mediaSession = MediaSession.Builder(this, player).build()
}
// Remember to release the player and media session in onDestroy
override fun onDestroy() {
mediaSession?.run {
player.release()
release()
mediaSession = null
}
super.onDestroy()
}
}
Java
public class PlaybackService extends MediaSessionService {
private MediaSession mediaSession = null;
@Override
public void onCreate() {
super.onCreate();
ExoPlayer player = new ExoPlayer.Builder(this).build();
mediaSession = new MediaSession.Builder(this, player).build();
}
@Override
public void onDestroy() {
mediaSession.getPlayer().release();
mediaSession.release();
mediaSession = null;
super.onDestroy();
}
}
In your manifest, declare your Service class with a MediaSessionService
intent filter and request the FOREGROUND_SERVICE permission to run a
foreground service:
<service
android:name=".PlaybackService"
android:foregroundServiceType="mediaPlayback"
android:exported="true">
<intent-filter>
<action android:name="androidx.media3.session.MediaSessionService"/>
</intent-filter>
</service>
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
Lastly, in the class you created, override the onGetSession() method to
control client access to your media session. Return a MediaSession to accept
the connection request, or return null to reject the request.
Kotlin
// This example always accepts the connection request
override fun onGetSession(
controllerInfo: MediaSession.ControllerInfo
): MediaSession? = mediaSession
Java
@Override
public MediaSession onGetSession(MediaSession.ControllerInfo controllerInfo) {
// This example always accepts the connection request
return mediaSession;
}
Connecting to your UI
Now that your media session is in a Service separate from the Activity or
Fragment where your player UI lives, you can use a MediaController to link
them together. In the onStart() method of the Activity or Fragment with
your UI, create a SessionToken for your MediaSession, then use the
SessionToken to build a MediaController. Building a MediaController
happens asynchronously.
Kotlin
override fun onStart() {
val sessionToken = SessionToken(this, ComponentName(this, PlaybackService::class.java))
val controllerFuture = MediaController.Builder(this, sessionToken).buildAsync()
controllerFuture.addListener(
{
// Call controllerFuture.get() to retrieve the MediaController.
// MediaController implements the Player interface, so it can be
// attached to the PlayerView UI component.
playerView.setPlayer(controllerFuture.get())
},
MoreExecutors.directExecutor()
)
}
Java
@Override
public void onStart() {
SessionToken sessionToken =
new SessionToken(this, new ComponentName(this, PlaybackService.class));
ListenableFuture<MediaController> controllerFuture =
new MediaController.Builder(this, sessionToken).buildAsync();
controllerFuture.addListener(() -> {
// Call controllerFuture.get() to retrieve the MediaController.
// MediaController implements the Player interface, so it can be
// attached to the PlayerView UI component.
playerView.setPlayer(controllerFuture.get());
}, MoreExecutors.directExecutor())
}
MediaController implements the Player interface, so you can use the same
methods such as play() and pause() to control playback. Similar to other
components, remember to release the MediaController when it is no longer
needed in the onStop() lifecycle method of an Activity, by calling
MediaController.releaseFuture().
Publishing a notification
Foreground services are required to publish a notification while active. A
MediaSessionService will automatically create a MediaStyle notification
for you in the form of a MediaNotification. To provide a custom
notification, create a MediaNotification.Provider with
DefaultMediaNotificationProvider.Builder or by creating a custom
implementation of the provider interface. Add your provider to your
MediaSession with setMediaNotificationProvider.
Advertising your content library
A MediaLibraryService builds on a MediaSessionService by allowing client
apps to browse the media content provided by your app. Client apps implement a
MediaBrowser to interact with your MediaLibraryService.
Implementing a MediaLibraryService is similar to implementing a
MediaSessionService, except that in onGetSession() you should return a
MediaLibrarySession instead of a MediaSession. Compared to a
MediaSession.Callback, the MediaLibrarySession.Callback includes additional
methods that allow a browser client to navigate the content offered by your
library service.
Similar to the MediaSessionService, declare the MediaLibraryService in your
manifest and request the FOREGROUND_SERVICE permission to run a foreground
service:
<service
android:name=".PlaybackService"
android:foregroundServiceType="mediaPlayback"
android:exported="true">
<intent-filter>
<action android:name="androidx.media3.session.MediaLibraryService"/>
<action android:name="android.media.browse.MediaBrowserService"/>
</intent-filter>
</service>
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
The example above includes an intent filter for both the MediaLibraryService
and, for backward compatibility, the legacy MediaBrowserService. The
additional intent filter enables client apps using the MediaBrowserCompat API
to recognize your Service.
A MediaLibrarySession lets you serve your content library in a tree structure,
with a single root MediaItem. Each MediaItem in the tree can have any number
of children MediaItem nodes. You can serve a different root, or a different
tree, based on the client app's request. For example, the tree you return to a
client looking for a list of recommended media items might only contain the root
MediaItem and a single level of children MediaItem nodes, whereas the tree
you return to a different client app may represent a more complete library of
content.
Creating a MediaLibrarySession
A MediaLibrarySession extends the MediaSession API to add content browsing
APIs. Compared to the MediaSession callback, the MediaLibrarySession
callback adds methods such as:
onGetLibraryRoot()for when a client requests the rootMediaItemof a content treeonGetChildren()for when a client requests the children of aMediaItemin the content treeonGetSearchResult()for when a client requests search results from the content tree for a given query
Relevant callback methods will include a LibraryParams object with
additional signals about the type of content tree that a client app is
interested in.