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MediaRouter

class MediaRouter
kotlin.Any
   ↳ androidx.mediarouter.media.MediaRouter

MediaRouter allows applications to control the routing of media channels and streams from the current device to external speakers and destination devices.

A MediaRouter instance is retrieved through getInstance. Applications can query the media router about the currently selected route and its capabilities to determine how to send content to the route's destination. Applications can also send control requests to the route to ask the route's destination to perform certain remote control functions such as playing media.

See also MediaRouteProvider for information on how an application can publish new media routes to the media router.

The media router API is not thread-safe; all interactions with it must be done from the main thread of the process.

Summary

Nested classes

abstract

Interface for receiving events about media routing changes.

abstract

Callback which is invoked with the result of a media control request.

Provides information about a media route provider.

Provides information about a media route.

Constants

static Int

Flag for isRouteAvailable: Ignore the default route.

static Int

Flag for isRouteAvailable: Require an actual route to be matched.

static Int

Flag for addCallback: Request passive route discovery while this callback is registered, even on low-RAM devices.

static Int

Flag for addCallback: Actively scan for routes while this callback is registered.

static Int

Flag for addCallback: Request passive route discovery while this callback is registered, except on low-RAM devices.

static Int

Flag for addCallback: Do not filter route events.

static Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the user pressed the disconnect button to disconnect and keep playing.

static Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the user selected a different route.

static Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the user pressed the stop casting button.

static Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the reason the route was unselected is unknown.

Public methods

Unit

Registers a callback to discover routes that match the selector and to receive events when they change.

Unit
addCallback(@NonNull selector: MediaRouteSelector, @NonNull callback: MediaRouter.Callback, flags: Int)

Registers a callback to discover routes that match the selector and to receive events when they change.

Unit
addProvider(@NonNull providerInstance: MediaRouteProvider)

Registers a media route provider within this application process.

Unit
addRemoteControlClient(@NonNull remoteControlClient: Any)

Adds a remote control client to enable remote control of the volume of the selected route.

MediaRouter.RouteInfo!

Gets a bluetooth route for playing media content on the system.

MediaRouter.RouteInfo

Gets the default route for playing media content on the system.

static MediaRouter!
getInstance(@NonNull context: Context)

Gets an instance of the media router service associated with the context.

MediaSessionCompat.Token!

MutableList<MediaRouter.ProviderInfo!>!

Gets information about the route providers currently known to this media router.

MutableList<MediaRouter.RouteInfo!>!

Gets information about the routes currently known to this media router.

MediaRouter.RouteInfo

Gets the currently selected route.

Boolean
isRouteAvailable(@NonNull selector: MediaRouteSelector, flags: Int)

Returns true if there is a route that matches the specified selector.

Unit

Removes the specified callback.

Unit
removeProvider(@NonNull providerInstance: MediaRouteProvider)

Unregisters a media route provider within this application process.

Unit
removeRemoteControlClient(@NonNull remoteControlClient: Any)

Removes a remote control client.

Unit

Selects the specified route.

Unit
setMediaSession(mediaSession: Any!)

Sets the media session to enable remote control of the volume of the selected route.

Unit

Sets a compat media session to enable remote control of the volume of the selected route.

Unit
unselect(reason: Int)

Unselects the current route and selects the default route instead.

MediaRouter.RouteInfo

Returns the selected route if it matches the specified selector, otherwise selects the default route and returns it.

Constants

AVAILABILITY_FLAG_IGNORE_DEFAULT_ROUTE

static val AVAILABILITY_FLAG_IGNORE_DEFAULT_ROUTE: Int

Flag for isRouteAvailable: Ignore the default route.

This flag is used to determine whether a matching non-default route is available. This constraint may be used to decide whether to offer the route chooser dialog to the user. There is no point offering the chooser if there are no non-default choices.

Value: 1 << 0

AVAILABILITY_FLAG_REQUIRE_MATCH

static val AVAILABILITY_FLAG_REQUIRE_MATCH: Int

Flag for isRouteAvailable: Require an actual route to be matched.

If this flag is not set, then isRouteAvailable will return true if it is possible to discover a matching route even if discovery is not in progress or if no matching route has yet been found. This feature is used to save resources by removing the need to perform passive route discovery on low-RAM devices.

If this flag is set, then isRouteAvailable will only return true if a matching route has actually been discovered.

Value: 1 << 1

CALLBACK_FLAG_FORCE_DISCOVERY

static val CALLBACK_FLAG_FORCE_DISCOVERY: Int

Flag for addCallback: Request passive route discovery while this callback is registered, even on low-RAM devices.

This flag has a significant performance impact on low-RAM devices since it may cause many media route providers to be started simultaneously. It is much better to use CALLBACK_FLAG_REQUEST_DISCOVERY instead to avoid performing passive discovery on these devices altogether. Refer to addCallback for details.

Value: 1 << 3

CALLBACK_FLAG_PERFORM_ACTIVE_SCAN

static val CALLBACK_FLAG_PERFORM_ACTIVE_SCAN: Int

Flag for addCallback: Actively scan for routes while this callback is registered.

When this flag is specified, the media router will actively scan for new routes. Certain routes, such as wifi display routes, may not be discoverable except when actively scanning. This flag is typically used when the route picker dialog has been opened by the user to ensure that the route information is up to date.

Active scanning may consume a significant amount of power and may have intrusive effects on wireless connectivity. Therefore it is important that active scanning only be requested when it is actually needed to satisfy a user request to discover and select a new route.

This flag implies CALLBACK_FLAG_REQUEST_DISCOVERY but performing active scans is much more expensive than a normal discovery request.

Value: 1 << 0

CALLBACK_FLAG_REQUEST_DISCOVERY

static val CALLBACK_FLAG_REQUEST_DISCOVERY: Int

Flag for addCallback: Request passive route discovery while this callback is registered, except on low-RAM devices.

When this flag is specified, the media router will try to discover routes. Although route discovery is intended to be efficient, checking for new routes may result in some network activity and could slowly drain the battery. Therefore applications should only specify CALLBACK_FLAG_REQUEST_DISCOVERY when they are running in the foreground and would like to provide the user with the option of connecting to new routes.

Applications should typically add a callback using this flag in the activity's onStart method and remove it in the onStop method. The MediaRouteDiscoveryFragment fragment may also be used for this purpose.

On low-RAM devices this flag will be ignored. Refer to addCallback for details.

Value: 1 << 2

CALLBACK_FLAG_UNFILTERED_EVENTS

static val CALLBACK_FLAG_UNFILTERED_EVENTS: Int

Flag for addCallback: Do not filter route events.

When this flag is specified, the callback will be invoked for events that affect any route even if they do not match the callback's filter.

Value: 1 << 1

UNSELECT_REASON_DISCONNECTED

static val UNSELECT_REASON_DISCONNECTED: Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the user pressed the disconnect button to disconnect and keep playing.

Value: 1

UNSELECT_REASON_ROUTE_CHANGED

static val UNSELECT_REASON_ROUTE_CHANGED: Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the user selected a different route.

Value: 3

UNSELECT_REASON_STOPPED

static val UNSELECT_REASON_STOPPED: Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the user pressed the stop casting button.

Value: 2

UNSELECT_REASON_UNKNOWN

static val UNSELECT_REASON_UNKNOWN: Int

Passed to androidx.mediarouter.media.MediaRouteProvider.RouteController#onUnselect(int) and Callback#onRouteUnselected(MediaRouter, RouteInfo, int) when the reason the route was unselected is unknown.

Value: 0

Public methods

addCallback

fun addCallback(selector: MediaRouteSelector!, callback: MediaRouter.Callback!): Unit

Registers a callback to discover routes that match the selector and to receive events when they change.

This is a convenience method that has the same effect as calling addCallback(MediaRouteSelector, Callback, int) without flags.

Parameters
selector MediaRouteSelector!: A route selector that indicates the kinds of routes that the callback would like to discover.
callback MediaRouteSelector!: The callback to add.

See Also

addCallback

fun addCallback(@NonNull selector: MediaRouteSelector, @NonNull callback: MediaRouter.Callback, flags: Int): Unit

Registers a callback to discover routes that match the selector and to receive events when they change.

The selector describes the kinds of routes that the application wants to discover. For example, if the application wants to use live audio routes then it should include the live audio media control intent category in its selector when it adds a callback to the media router. The selector may include any number of categories.

If the callback has already been registered, then the selector is added to the set of selectors being monitored by the callback.

By default, the callback will only be invoked for events that affect routes that match the specified selector. Event filtering may be disabled by specifying the CALLBACK_FLAG_UNFILTERED_EVENTS flag when the callback is registered.

Applications should use the isRouteAvailable method to determine whether is it possible to discover a route with the desired capabilities and therefore whether the media route button should be shown to the user.

The CALLBACK_FLAG_REQUEST_DISCOVERY flag should be used while the application is in the foreground to request that passive discovery be performed if there are sufficient resources to allow continuous passive discovery. On low-RAM devices this flag will be ignored to conserve resources.

The CALLBACK_FLAG_FORCE_DISCOVERY flag should be used when passive discovery absolutely must be performed, even on low-RAM devices. This flag has a significant performance impact on low-RAM devices since it may cause many media route providers to be started simultaneously. It is much better to use CALLBACK_FLAG_REQUEST_DISCOVERY instead to avoid performing passive discovery on these devices altogether.

The CALLBACK_FLAG_PERFORM_ACTIVE_SCAN flag should be used when the media route chooser dialog is showing to confirm the presence of available routes that the user may connect to. This flag may use substantially more power.

Example

public class MyActivity extends Activity {
          private MediaRouter mRouter;
          private MediaRouter.Callback mCallback;
          private MediaRouteSelector mSelector;
     
          protected void onCreate(Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
     
              mRouter = Mediarouter.getInstance(this);
              mCallback = new MyCallback();
              mSelector = new MediaRouteSelector.Builder()
                      .addControlCategory(MediaControlIntent.CATEGORY_LIVE_AUDIO)
                      .addControlCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)
                      .build();
          }
     
          // Add the callback on start to tell the media router what kinds of routes
          // the application is interested in so that it can try to discover suitable ones.
          public void onStart() {
              super.onStart();
     
              mediaRouter.addCallback(mSelector, mCallback,
                      MediaRouter.CALLBACK_FLAG_REQUEST_DISCOVERY);
     
              MediaRouter.RouteInfo route = mediaRouter.updateSelectedRoute(mSelector);
              // do something with the route...
          }
     
          // Remove the selector on stop to tell the media router that it no longer
          // needs to invest effort trying to discover routes of these kinds for now.
          public void onStop() {
              super.onStop();
     
              mediaRouter.removeCallback(mCallback);
          }
     
          private final class MyCallback extends MediaRouter.Callback {
              // Implement callback methods as needed.
          }
      }
      
Parameters
selector MediaRouteSelector: A route selector that indicates the kinds of routes that the callback would like to discover.
callback MediaRouteSelector: The callback to add.
flags MediaRouteSelector: Flags to control the behavior of the callback. May be zero or a combination of CALLBACK_FLAG_PERFORM_ACTIVE_SCAN and CALLBACK_FLAG_UNFILTERED_EVENTS.

See Also

addProvider

fun addProvider(@NonNull providerInstance: MediaRouteProvider): Unit

Registers a media route provider within this application process.

The provider will be added to the list of providers that all MediaRouter instances within this process can use to discover routes.

Parameters
providerInstance MediaRouteProvider: The media route provider instance to add.

addRemoteControlClient

fun addRemoteControlClient(@NonNull remoteControlClient: Any): Unit

Adds a remote control client to enable remote control of the volume of the selected route.

The remote control client must have previously been registered with the audio manager using the AudioManager.registerRemoteControlClient method.

Parameters
remoteControlClient Any: The android.media.RemoteControlClient to register.

getBluetoothRoute

fun getBluetoothRoute(): MediaRouter.RouteInfo!

Gets a bluetooth route for playing media content on the system.

Return
MediaRouter.RouteInfo!: A bluetooth route, if exist, otherwise null.

getDefaultRoute

@NonNull fun getDefaultRoute(): MediaRouter.RouteInfo

Gets the default route for playing media content on the system.

The system always provides a default route.

Return
MediaRouter.RouteInfo: The default route, which is guaranteed to never be null.

getInstance

static fun getInstance(@NonNull context: Context): MediaRouter!

Gets an instance of the media router service associated with the context.

The application is responsible for holding a strong reference to the returned MediaRouter instance, such as by storing the instance in a field of the android.app.Activity, to ensure that the media router remains alive as long as the application is using its features.

In other words, the support library only holds a weak reference to each media router instance. When there are no remaining strong references to the media router instance, all of its callbacks will be removed and route discovery will no longer be performed on its behalf.

Return
MediaRouter!: The media router instance for the context. The application must hold a strong reference to this object as long as it is in use.

getMediaSessionToken

fun getMediaSessionToken(): MediaSessionCompat.Token!

getProviders

fun getProviders(): MutableList<MediaRouter.ProviderInfo!>!

Gets information about the route providers currently known to this media router.

getRoutes

fun getRoutes(): MutableList<MediaRouter.RouteInfo!>!

Gets information about the routes currently known to this media router.

getSelectedRoute

@NonNull fun getSelectedRoute(): MediaRouter.RouteInfo

Gets the currently selected route.

The application should examine the route's media control intent filters to assess the capabilities of the route before attempting to use it.

Example

public boolean playMovie() {
          MediaRouter mediaRouter = MediaRouter.getInstance(context);
          MediaRouter.RouteInfo route = mediaRouter.getSelectedRoute();
     
          // First try using the remote playback interface, if supported.
          if (route.supportsControlCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK)) {
              // The route supports remote playback.
              // Try to send it the Uri of the movie to play.
              Intent intent = new Intent(MediaControlIntent.ACTION_PLAY);
              intent.addCategory(MediaControlIntent.CATEGORY_REMOTE_PLAYBACK);
              intent.setDataAndType("http://example.com/videos/movie.mp4", "video/mp4");
              if (route.supportsControlRequest(intent)) {
                  route.sendControlRequest(intent, null);
                  return true; // sent the request to play the movie
              }
          }
     
          // If remote playback was not possible, then play locally.
          if (route.supportsControlCategory(MediaControlIntent.CATEGORY_LIVE_VIDEO)) {
              // The route supports live video streaming.
              // Prepare to play content locally in a window or in a presentation.
              return playMovieInWindow();
          }
     
          // Neither interface is supported, so we can't play the movie to this route.
          return false;
      }
      
Return
MediaRouter.RouteInfo: The selected route, which is guaranteed to never be null.

isRouteAvailable

fun isRouteAvailable(@NonNull selector: MediaRouteSelector, flags: Int): Boolean

Returns true if there is a route that matches the specified selector.

This method returns true if there are any available routes that match the selector regardless of whether they are enabled or disabled. If the AVAILABILITY_FLAG_IGNORE_DEFAULT_ROUTE flag is specified, then the method will only consider non-default routes.

On low-RAM devices this method will return true if it is possible to discover a matching route even if discovery is not in progress or if no matching route has yet been found. Use AVAILABILITY_FLAG_REQUIRE_MATCH to require an actual match.

Parameters
selector MediaRouteSelector: The selector to match.
flags MediaRouteSelector: Flags to control the determination of whether a route may be available. May be zero or some combination of AVAILABILITY_FLAG_IGNORE_DEFAULT_ROUTE and AVAILABILITY_FLAG_REQUIRE_MATCH.
Return
Boolean: True if a matching route may be available.

removeCallback

fun removeCallback(@NonNull callback: MediaRouter.Callback): Unit

Removes the specified callback. It will no longer receive events about changes to media routes.

Parameters
callback MediaRouter.Callback: The callback to remove.

See Also

removeProvider

fun removeProvider(@NonNull providerInstance: MediaRouteProvider): Unit

Unregisters a media route provider within this application process.

The provider will be removed from the list of providers that all MediaRouter instances within this process can use to discover routes.

Parameters
providerInstance MediaRouteProvider: The media route provider instance to remove.

removeRemoteControlClient

fun removeRemoteControlClient(@NonNull remoteControlClient: Any): Unit

Removes a remote control client.

Parameters
remoteControlClient Any: The android.media.RemoteControlClient to unregister.

selectRoute

fun selectRoute(@NonNull route: MediaRouter.RouteInfo): Unit

Selects the specified route.

Parameters
route MediaRouter.RouteInfo: The route to select.

setMediaSession

fun setMediaSession(mediaSession: Any!): Unit

Sets the media session to enable remote control of the volume of the selected route. This should be used instead of addRemoteControlClient when using media sessions. Set the session to null to clear it.

Parameters
mediaSession Any!: The android.media.session.MediaSession to use.

setMediaSessionCompat

fun setMediaSessionCompat(mediaSession: MediaSessionCompat!): Unit

Sets a compat media session to enable remote control of the volume of the selected route. This should be used instead of addRemoteControlClient when using MediaSessionCompat. Set the session to null to clear it.

Parameters
mediaSession MediaSessionCompat!:

unselect

fun unselect(reason: Int): Unit

Unselects the current route and selects the default route instead.

The reason given must be one of:

Parameters
reason Int: The reason for disconnecting the current route.

updateSelectedRoute

@NonNull fun updateSelectedRoute(@NonNull selector: MediaRouteSelector): MediaRouter.RouteInfo

Returns the selected route if it matches the specified selector, otherwise selects the default route and returns it. If there is one live audio route (usually Bluetooth A2DP), it will be selected instead of default route.

Parameters
selector MediaRouteSelector: The selector to match.
Return
MediaRouter.RouteInfo: The previously selected route if it matched the selector, otherwise the newly selected default route which is guaranteed to never be null.