android13/external/exoplayer/tree_15dc86382f17a24a3e881e52e31a810c1ea44b49/docs/hello-world.md

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Another way to get started is to work through the ExoPlayer codelab. {:.info}

For simple use cases, getting started with ExoPlayer consists of implementing the following steps:

1. Add ExoPlayer as a dependency to your project.
2. Create an ExoPlayer instance.
3. Attach the player to a view (for video output and user input).
4. Prepare the player with a MediaItem to play.
5. Release the player when done.

These steps are described in more detail below. For a complete example, refer to PlayerActivity in the [main demo app][].

Adding ExoPlayer as a dependency

Add ExoPlayer modules

The easiest way to get started using ExoPlayer is to add it as a gradle dependency in the build.gradle file of your app module. The following will add a dependency to the full library:

implementation 'com.google.android.exoplayer:exoplayer:2.X.X'

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where 2.X.X is your preferred version (the latest version can be found by consulting the [release notes][]).

As an alternative to the full library, you can depend on only the library modules that you actually need. For example the following will add dependencies on the Core, DASH and UI library modules, as might be required for an app that only plays DASH content:

implementation 'com.google.android.exoplayer:exoplayer-core:2.X.X'
implementation 'com.google.android.exoplayer:exoplayer-dash:2.X.X'
implementation 'com.google.android.exoplayer:exoplayer-ui:2.X.X'

{: .language-gradle}

When depending on individual modules they must all be the same version.

The available library modules are listed below. Adding a dependency to the full ExoPlayer library is equivalent to adding dependencies on all of the library modules individually.

• exoplayer-core: Core functionality (required).
• exoplayer-dash: Support for DASH content.
• exoplayer-hls: Support for HLS content.
• exoplayer-rtsp: Support for RTSP content.
• exoplayer-smoothstreaming: Support for SmoothStreaming content.
• exoplayer-transformer: Media transformation functionality.
• exoplayer-ui: UI components and resources for use with ExoPlayer.

In addition to library modules, ExoPlayer has extension modules that depend on external libraries to provide additional functionality. Some extensions are available from the Maven repository, whereas others must be built manually. Browse the [extensions directory][] and their individual READMEs for details.

More information on the library and extension modules that are available can be found on the [Google Maven ExoPlayer page][].

Turn on Java 8 support

If not enabled already, you need to turn on Java 8 support in all build.gradle files depending on ExoPlayer, by adding the following to the android section:

compileOptions {
  targetCompatibility JavaVersion.VERSION_1_8
}

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Enable multidex

If your Gradle minSdkVersion is 20 or lower, you should enable multidex in order to prevent build errors.

Creating the player

You can create an ExoPlayer instance using ExoPlayer.Builder, which provides a range of customization options. The code below is the simplest example of creating an instance.

ExoPlayer player = new ExoPlayer.Builder(context).build();

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A note on threading

ExoPlayer instances must be accessed from a single application thread. For the vast majority of cases this should be the application's main thread. Using the application's main thread is a requirement when using ExoPlayer's UI components or the IMA extension.

The thread on which an ExoPlayer instance must be accessed can be explicitly specified by passing a Looper when creating the player. If no Looper is specified, then the Looper of the thread that the player is created on is used, or if that thread does not have a Looper, the Looper of the application's main thread is used. In all cases the Looper of the thread from which the player must be accessed can be queried using Player.getApplicationLooper.

If you see IllegalStateException being thrown with the message "Player is accessed on the wrong thread", then some code in your app is accessing an ExoPlayer instance on the wrong thread (the exception's stack trace shows you where). You can temporarily opt out from these exceptions being thrown by calling ExoPlayer.setThrowsWhenUsingWrongThread(false), in which case the issue will be logged as a warning instead. Using this opt out is not safe and may result in unexpected or obscure errors. It will be removed in ExoPlayer 2.16. {:.info}

For more information about ExoPlayer's threading model, see the ["Threading model" section of the ExoPlayer Javadoc][].

Attaching the player to a view

The ExoPlayer library provides a range of pre-built UI components for media playback. These include StyledPlayerView, which encapsulates a StyledPlayerControlView, a SubtitleView, and a Surface onto which video is rendered. A StyledPlayerView can be included in your application's layout xml. Binding the player to the view is as simple as:

// Bind the player to the view.
playerView.setPlayer(player);

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You can also use StyledPlayerControlView as a standalone component, which is useful for audio only use cases.

Use of ExoPlayer's pre-built UI components is optional. For video applications that implement their own UI, the target SurfaceView, TextureView, SurfaceHolder or Surface can be set using ExoPlayer's setVideoSurfaceView, setVideoTextureView, setVideoSurfaceHolder and setVideoSurface methods respectively. ExoPlayer's addTextOutput method can be used to receive captions that should be rendered during playback.

Populating the playlist and preparing the player

In ExoPlayer every piece of media is represented by a MediaItem. To play a piece of media you need to build a corresponding MediaItem, add it to the player, prepare the player, and call play to start the playback:

// Build the media item.
MediaItem mediaItem = MediaItem.fromUri(videoUri);
// Set the media item to be played.
player.setMediaItem(mediaItem);
// Prepare the player.
player.prepare();
// Start the playback.
player.play();

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ExoPlayer supports playlists directly, so it's possible to prepare the player with multiple media items to be played one after the other:

// Build the media items.
MediaItem firstItem = MediaItem.fromUri(firstVideoUri);
MediaItem secondItem = MediaItem.fromUri(secondVideoUri);
// Add the media items to be played.
player.addMediaItem(firstItem);
player.addMediaItem(secondItem);
// Prepare the player.
player.prepare();
// Start the playback.
player.play();

{: .language-java}

The playlist can be updated during playback without the need to prepare the player again. Read more about populating and manipulating the playlist on the [Playlists page][]. Read more about the different options available when building media items, such as clipping and attaching subtitle files, on the [Media items page][].

Prior to ExoPlayer 2.12, the player needed to be given a MediaSource rather than media items. From 2.12 onwards, the player converts media items to the MediaSource instances that it needs internally. Read more about this process and how it can be customized on the [Media sources page][]. It's still possible to provide MediaSource instances directly to the player using ExoPlayer.setMediaSource(s) and ExoPlayer.addMediaSource(s). {:.info}

Controlling the player

Once the player has been prepared, playback can be controlled by calling methods on the player. Some of the most commonly used methods are listed below.

• play and pause start and pause playback.
• seekTo allows seeking within the media.
• hasPrevious, hasNext, previous and next allow navigating through the playlist.
• setRepeatMode controls if and how media is looped.
• setShuffleModeEnabled controls playlist shuffling.
• setPlaybackParameters adjusts playback speed and audio pitch.

If the player is bound to a StyledPlayerView or StyledPlayerControlView, then user interaction with these components will cause corresponding methods on the player to be invoked.

Releasing the player

It's important to release the player when it's no longer needed, so as to free up limited resources such as video decoders for use by other applications. This can be done by calling ExoPlayer.release.

[main demo app]: {{ site.release_v2 }}/demos/main/ [extensions directory]: {{ site.release_v2 }}/extensions/ [release notes]: {{ site.release_v2 }}/RELEASENOTES.md ["Threading model" section of the ExoPlayer Javadoc]: {{ site.exo_sdk }}/ExoPlayer.html [Playlists page]: {{ site.baseurl }}/playlists.html [Media items page]: {{ site.baseurl }}/media-items.html [Media sources page]: {{ site.baseurl }}/media-sources.html [Google Maven ExoPlayer page]: https://maven.google.com/web/index.html#com.google.android.exoplayer