public
final
class
MediaRouter
extends Object
java.lang.Object | |
↳ | android.support.v7.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(Context)
. 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.
Nested classes | |
---|---|
class |
MediaRouter.Callback
Interface for receiving events about media routing changes. |
class |
MediaRouter.ControlRequestCallback
Callback which is invoked with the result of a media control request. |
class |
MediaRouter.ProviderInfo
Provides information about a media route provider. |
class |
MediaRouter.RouteInfo
Provides information about a media route. |
Public methods | |
---|---|
void
|
addCallback(MediaRouteSelector selector, MediaRouter.Callback callback, int flags)
Registers a callback to discover routes that match the selector and to receive events when they change. |
void
|
addCallback(MediaRouteSelector selector, MediaRouter.Callback callback)
Registers a callback to discover routes that match the selector and to receive events when they change. |
void
|
addProvider(MediaRouteProvider providerInstance)
Registers a media route provider within this application process. |
void
|
addRemoteControlClient(Object remoteControlClient)
Adds a remote control client to enable remote control of the volume of the selected route. |
MediaRouter.RouteInfo
|
getDefaultRoute()
Gets the default route for playing media content on the system. |
static
MediaRouter
|
getInstance(Context context)
Gets an instance of the media router service associated with the context. |
MediaSessionCompat.Token
|
getMediaSessionToken()
|
List<MediaRouter.ProviderInfo>
|
getProviders()
Gets information about the |
List<MediaRouter.RouteInfo>
|
getRoutes()
Gets information about the |
MediaRouter.RouteInfo
|
getSelectedRoute()
Gets the currently selected route. |
boolean
|
isRouteAvailable(MediaRouteSelector selector, int flags)
Returns true if there is a route that matches the specified selector. |
void
|
removeCallback(MediaRouter.Callback callback)
Removes the specified callback. |
void
|
removeProvider(MediaRouteProvider providerInstance)
Unregisters a media route provider within this application process. |
void
|
removeRemoteControlClient(Object remoteControlClient)
Removes a remote control client. |
void
|
selectRoute(MediaRouter.RouteInfo route)
Selects the specified route. |
void
|
setMediaSession(Object mediaSession)
Sets the media session to enable remote control of the volume of the selected route. |
void
|
setMediaSessionCompat(MediaSessionCompat mediaSession)
Sets a compat media session to enable remote control of the volume of the selected route. |
void
|
unselect(int reason)
Unselects the current round and selects the default route instead. |
MediaRouter.RouteInfo
|
updateSelectedRoute(MediaRouteSelector selector)
Returns the selected route if it matches the specified selector, otherwise selects the default route and returns it. |
Inherited methods | |
---|---|
From
class
java.lang.Object
|
int AVAILABILITY_FLAG_IGNORE_DEFAULT_ROUTE
Flag for isRouteAvailable(MediaRouteSelector, int)
: 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.
Constant Value: 1 (0x00000001)
int AVAILABILITY_FLAG_REQUIRE_MATCH
Flag for isRouteAvailable(MediaRouteSelector, int)
: Require an actual route to be matched.
If this flag is not set, then isRouteAvailable(MediaRouteSelector, int)
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(MediaRouteSelector, int)
will only return true if
a matching route has actually been discovered.
Constant Value: 2 (0x00000002)
int CALLBACK_FLAG_FORCE_DISCOVERY
Flag for addCallback(MediaRouteSelector, MediaRouter.Callback)
: 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.
See also:
Constant Value: 8 (0x00000008)
int CALLBACK_FLAG_PERFORM_ACTIVE_SCAN
Flag for addCallback(MediaRouteSelector, MediaRouter.Callback)
: 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.
See also:
Constant Value: 1 (0x00000001)
int CALLBACK_FLAG_REQUEST_DISCOVERY
Flag for addCallback(MediaRouteSelector, MediaRouter.Callback)
: 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.
See also:
Constant Value: 4 (0x00000004)
int CALLBACK_FLAG_UNFILTERED_EVENTS
Flag for addCallback(MediaRouteSelector, MediaRouter.Callback)
: 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.
Constant Value: 2 (0x00000002)
int UNSELECT_REASON_DISCONNECTED
Passed to onUnselect(int)
and onRouteUnselected(MediaRouter, RouteInfo, int)
when the user pressed
the disconnect button to disconnect and keep playing.
Constant Value: 1 (0x00000001)
int UNSELECT_REASON_ROUTE_CHANGED
Passed to onUnselect(int)
and onRouteUnselected(MediaRouter, RouteInfo, int)
when the user selected
a different route.
Constant Value: 3 (0x00000003)
int UNSELECT_REASON_STOPPED
Passed to onUnselect(int)
and onRouteUnselected(MediaRouter, RouteInfo, int)
when the user pressed
the stop casting button.
Constant Value: 2 (0x00000002)
int UNSELECT_REASON_UNKNOWN
Passed to onUnselect(int)
and onRouteUnselected(MediaRouter, RouteInfo, int)
when the reason the route
was unselected is unknown.
Constant Value: 0 (0x00000000)
void addCallback (MediaRouteSelector selector, MediaRouter.Callback callback, int flags)
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(MediaRouteSelector, int)
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.
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 |
MediaRouter.Callback :
The callback to add. |
flags |
int :
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:
void addCallback (MediaRouteSelector selector, MediaRouter.Callback callback)
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 |
MediaRouter.Callback :
The callback to add. |
See also:
void addProvider (MediaRouteProvider providerInstance)
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. |
void addRemoteControlClient (Object remoteControlClient)
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 |
Object :
The RemoteControlClient to register.
|
MediaRouter.RouteInfo getDefaultRoute ()
Gets the default route for playing media content on the system.
The system always provides a default route.
Returns | |
---|---|
MediaRouter.RouteInfo |
The default route, which is guaranteed to never be null. |
MediaRouter getInstance (Context context)
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 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.
Parameters | |
---|---|
context |
Context
|
Returns | |
---|---|
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. |
MediaSessionCompat.Token getMediaSessionToken ()
Returns | |
---|---|
MediaSessionCompat.Token |
List<MediaRouter.ProviderInfo> getProviders ()
Gets information about the route providers
currently known to this media router.
Returns | |
---|---|
List<MediaRouter.ProviderInfo> |
List<MediaRouter.RouteInfo> getRoutes ()
Gets information about the routes
currently known to
this media router.
Returns | |
---|---|
List<MediaRouter.RouteInfo> |
MediaRouter.RouteInfo getSelectedRoute ()
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.
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; }
Returns | |
---|---|
MediaRouter.RouteInfo |
The selected route, which is guaranteed to never be null. |
boolean isRouteAvailable (MediaRouteSelector selector, int flags)
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 |
int :
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 . |
Returns | |
---|---|
boolean |
True if a matching route may be available. |
void removeCallback (MediaRouter.Callback callback)
Removes the specified callback. It will no longer receive events about changes to media routes.
Parameters | |
---|---|
callback |
MediaRouter.Callback :
The callback to remove. |
void removeProvider (MediaRouteProvider providerInstance)
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. |
void removeRemoteControlClient (Object remoteControlClient)
Removes a remote control client.
Parameters | |
---|---|
remoteControlClient |
Object :
The RemoteControlClient
to unregister.
|
void selectRoute (MediaRouter.RouteInfo route)
Selects the specified route.
Parameters | |
---|---|
route |
MediaRouter.RouteInfo :
The route to select.
|
void setMediaSession (Object mediaSession)
Sets the media session to enable remote control of the volume of the
selected route. This should be used instead of
addRemoteControlClient(Object)
when using media sessions. Set the
session to null to clear it.
Parameters | |
---|---|
mediaSession |
Object :
The MediaSession to
use.
|
void setMediaSessionCompat (MediaSessionCompat mediaSession)
Sets a compat media session to enable remote control of the volume of the
selected route. This should be used instead of
addRemoteControlClient(Object)
when using MediaSessionCompat
.
Set the session to null to clear it.
void unselect (int reason)
Unselects the current round and selects the default route instead.
The reason given must be one of:
UNSELECT_REASON_UNKNOWN
UNSELECT_REASON_DISCONNECTED
UNSELECT_REASON_STOPPED
UNSELECT_REASON_ROUTE_CHANGED
Parameters | |
---|---|
reason |
int :
The reason for disconnecting the current route.
|
MediaRouter.RouteInfo updateSelectedRoute (MediaRouteSelector selector)
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. |
Returns | |
---|---|
MediaRouter.RouteInfo |
The previously selected route if it matched the selector, otherwise the newly selected default route which is guaranteed to never be null. |