MessageApi

public interface MessageApi

Exposes an API for components to send messages to other nodes.

Messages are delivered to connected network nodes. A message is considered successful if it has been queued for delivery to the specified node. A message will only be queued if the specified node is connected. The DataApi should be used for messages to nodes which are not currently connected (to be delivered on connection).

Messages should generally contain ephemeral, small payloads. Use {@linkplain Asset assets} with the DataApi to store more persistent or larger data efficiently.

A message is private to the application that created it and accessible only by that application on other nodes.

Nested Class Summary

@interface MessageApi.FilterType  
interface MessageApi.MessageListener Used with addListener(GoogleApiClient, MessageApi.MessageListener) to receive message events. 
interface MessageApi.SendMessageResult Contains the request id assigned to the message. 

Constant Summary

String ACTION_MESSAGE_RECEIVED Message received action for use in manifest-based listener filters.
int FILTER_LITERAL Filter type for addListener(GoogleApiClient, MessageListener, Uri, int), if this filter is set, the given URI will be taken as a literal path, and the operation will apply to the matching message only.
int FILTER_PREFIX Filter type for addListener(GoogleApiClient, MessageListener, Uri, int), if this filter is set, the given URI will be taken as a path prefix, and the operation will apply to all matching messages.
int UNKNOWN_REQUEST_ID A value returned by getRequestId() when sendMessage(GoogleApiClient, String, String, byte[]) fails.

Public Method Summary

abstract PendingResult<Status>
addListener(GoogleApiClient client, MessageApi.MessageListener listener, Uri uri, int filterType)
Registers a listener to be notified of received messages.
abstract PendingResult<Status>
addListener(GoogleApiClient client, MessageApi.MessageListener listener)
Registers a listener to be notified of received messages.
abstract PendingResult<Status>
removeListener(GoogleApiClient client, MessageApi.MessageListener listener)
Removes a message listener which was previously added through addListener(GoogleApiClient, MessageListener).
abstract PendingResult<MessageApi.SendMessageResult>
sendMessage(GoogleApiClient client, String nodeId, String path, byte[] data)
Sends byte[] data to the specified node.

Constants

public static final String ACTION_MESSAGE_RECEIVED

Message received action for use in manifest-based listener filters.

See Also
Constant Value: "com.google.android.gms.wearable.MESSAGE_RECEIVED"

public static final int FILTER_LITERAL

Filter type for addListener(GoogleApiClient, MessageListener, Uri, int), if this filter is set, the given URI will be taken as a literal path, and the operation will apply to the matching message only.

Constant Value: 0

public static final int FILTER_PREFIX

Filter type for addListener(GoogleApiClient, MessageListener, Uri, int), if this filter is set, the given URI will be taken as a path prefix, and the operation will apply to all matching messages.

Constant Value: 1

public static final int UNKNOWN_REQUEST_ID

A value returned by getRequestId() when sendMessage(GoogleApiClient, String, String, byte[]) fails.

Constant Value: -1

Public Methods

public abstract PendingResult<Status> addListener (GoogleApiClient client, MessageApi.MessageListener listener, Uri uri, int filterType)

Registers a listener to be notified of received messages. Calls to this method should be balanced with removeListener(GoogleApiClient, MessageListener) to avoid leaking resources.

uri and filterType can be used to filter the messages sent to the listener. For example, if uri and filterType create a path prefix filter, then only messages matching that prefix will be notified. The uri follows the rules of the <data> element of <intent-filter>. The path is ignored if a URI host is not specified. The host should be an Android Wear node ID, or * to match any node. i.e, you should use: 

wear://*/<path>
or 
wear://<nodeId>/<path>

Listener events will be called on the main thread, or the handler specified on client when it was built (using setHandler(Handler)).

Callers wishing to be notified of events in the background should use WearableListenerService.

public abstract PendingResult<Status> addListener (GoogleApiClient client, MessageApi.MessageListener listener)

Registers a listener to be notified of received messages. Calls to this method should be balanced with removeListener(GoogleApiClient, MessageListener) to avoid leaking resources.

Listener events will be called on the main thread, or the handler specified on client when it was built (using setHandler(Handler)).

Callers wishing to be notified of events in the background should use WearableListenerService.

public abstract PendingResult<Status> removeListener (GoogleApiClient client, MessageApi.MessageListener listener)

Removes a message listener which was previously added through addListener(GoogleApiClient, MessageListener).

public abstract PendingResult<MessageApi.SendMessageResult> sendMessage (GoogleApiClient client, String nodeId, String path, byte[] data)

Sends byte[] data to the specified node.

Parameters
nodeId identifier for a particular node on the Android Wear network. Valid targets may be obtained through getConnectedNodes(GoogleApiClient) or from the host in getUri().
path identifier used to specify a particular endpoint at the receiving node
data small array of information to pass to the target node. Generally not larger than 100k
Returns
  • a PendingResult that is set when the message is queued to be sent. A successful result doesn't guarantee delivery.