# cast.[framework](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework).AudioTracksManager

class static

Manages audio tracks.

Throws

:   `non-null Error` if the constructor is used directly.
    The `AudioTracksManager` should be instantiated
    by calling [cast.framework.PlayerManager#getAudioTracksManager](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.PlayerManager#getAudioTracksManager).

## Methods

### getActiveId

getActiveId() returns number

Gets the active audio track ID.

Returns

:   `nullable number`

### getActiveTrack

getActiveTrack() returns [cast.framework.messages.Track](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track)

Gets the active audio track.

Returns

:   `nullable https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track`

### getTrackById

getTrackById(id) returns [cast.framework.messages.Track](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track)

Gets the audio track that matches `id`.

| #### Parameter ||
|---|---|
| id | number |

Throws

:   `non-null Error` if `id` is invalid.

Returns

:   `nullable https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track`

### getTracks

getTracks() returns Array of non-null [cast.framework.messages.Track](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track)

Returns all audio tracks.

Returns

:   `non-null Array of non-null https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track`

### getTracksByLanguage

getTracksByLanguage(language) returns Array of non-null [cast.framework.messages.Track](https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track)

Gets all the audio tracks that match `language`.

| #### Parameter ||
|---|---|
| language | string Language tag as per RFC 5646. |

Throws

:   `non-null Error` if `language` is not available.

Returns

:   `non-null Array of non-null https://developers.google.com/cast/docs/reference/web_receiver/cast.framework.messages.Track`

### setActiveById

setActiveById(id)

Sets the audio track that matches `id` to the active state.

| #### Parameter ||
|---|---|
| id | number The track ID |

Throws

:   `non-null Error` if `id` is not an audio track ID.

### setActiveByLanguage

setActiveByLanguage(language)

Sets the first audio track that matches `language` to the active state.

| #### Parameter ||
|---|---|
| language | string Language tag as per RFC 5646. |

Throws

:   `non-null Error` if `language` is not available or invalid.