Send and Receiving Data using DataMap - Android Wearable

Question

I am working on an Android Wearable project and I am trying to send data from the mobile device to the Wearable emulator. I am trying log the received data in the wearable but it is not logging.

These are what I've done so far.

1) Open the Android Wear app to get the Emulator status to be "connected"

2) Connect my mobile device

3) run adb -d forward tcp:5601 tcp:5601 to connect mobile device with emulator

4) Implement GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener in the sending class in my mobile device and building client in onCreate:

    googleClient = new GoogleApiClient.Builder(this)
            .addApi(Wearable.API)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this)
            .build();

5) In my mobile device, create a dataItem, using 'weatherDescription" that logs perfectly, where I can using the DataApi to send to the wearable using putDataItem:

This is the log for weatherDescription: I/weatherDescription: scattered clouds

            putDataMapReq = PutDataMapRequest.create("/data");
            Log.i("weatherDescription", weatherDescription);
            putDataMapReq.getDataMap().putString("weatherDescription", weatherDescription);

            PutDataRequest putDataReq = putDataMapReq.asPutDataRequest();
            Wearable.DataApi.putDataItem(googleClient, putDataReq); 

5)Implement GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener in the receiving class (My custom watchface class) in my Wearable device and building client in onCreate:

    googleClient = new GoogleApiClient.Builder(this)
            .addApi(Wearable.API)
            .addConnectionCallbacks(this)
            .addOnConnectionFailedListener(this)
            .build();

6) Set up the listener in onConnect in the Wearable:

@Override
public void onConnected(Bundle bundle) {

    Wearable.DataApi.addListener(mGoogleApiClient, this).setResultCallback(new ResultCallback<Status>() {
        @Override
        public void onResult(Status status) {
            Log.i("myTag", String.valueOf(status));
        }
    });
}

It looks like it's connecting properly on the receiving/wearable end:

I/myTag: Status{statusCode=SUCCESS, resolution=null}

7) In onDataChanged, log the received information:

    public void onDataChanged(DataEventBuffer dataEventBuffer) {
        Log.i("myTag", "in on Data Changed");
        for (DataEvent event : dataEventBuffer){
            if(event.getType() == DataEvent.TYPE_CHANGED){
                DataItem item = event.getDataItem();

                if(item.getUri().getPath().compareTo("/data") == 0 ){
                    DataMap dataMap = DataMapItem.fromDataItem(item).getDataMap();

                    dataMap.getString("weatherDescription");

                    Log.i("myTag", dataMap.getString("weatherDescription"));
                }
            }
        }
    }

Answer 1

Sounds like your dataMap is not changing its values, Then it won't send data to the wearable.

You can send Long.toString(System.currentTimeMillis()) to verify that as it changes every time.

Answer 2

Here are some leads :

1. On your fifth point, try putting setUrgent() here :

   PutDataRequest putDataReq = putDataMapReq.asPutDataRequest().setUrgent();

Also, if you get a success in the callback, it means your data was sent successfully. It doesn't imply it was received well, or received at well.

2. Maybe you did, but do you call googleClient.connect() at onStart() or anywhere else ?

3. onDataChanged() is only called when the data put is really different, if you eep putting the same data, it won't be called. To test, you can add a timestamp to your DataMap.

4. You need to have the same package names for your mobile and wear applications for them to be able to exchange messages/data.

5. Maybe you can try implementing a WearableListenerService to receive the data on onDataChanged. The code is not different, it's just that this service is created when data is received, so you don't have to have your app open. Make sure you add the BIND_LISTENER action in this service intent filter on your manifest.

<service android:name=".AnalogWatchFaceConfigListenerService"> <intent-filter> <action android:name="com.google.android.gms.wearable.BIND_LISTENER" /> </intent-filter> </service>

Answer 3

First, try to log the result of putting the DataItem:

Wearable.DataApi.putDataItem(googleClient, putDataReq)
    .setResultCallback(new ResultCallback<DataApi.DataItemResult>() {
                @Override
                public void onResult(DataApi.DataItemResult dataItemResult) {
                    Log.d(TAG, "putDataItem status: "
                            + dataItemResult.getStatus().toString());
                }
            });

The dataItemResult.getStatus() call will tell you if something went wrong. Next, make sure you are listening to the onDataChanged() event. On your Wear app onConnected() method, add:

Wearable.DataApi.addListener(googleClient, yourListenerHere);

Finally, to force the data to be sent immediately to the Wear device, use setUrgent():

putDataMapReq = PutDataMapRequest.create("/data").setUrgent();

Hope that helps.

Answer 4

I finally figured it out. In the watchface side, I declared the Google Api Client instance, mGoogleApiClient, in the WeatherWatchFaceService class as opposed to the Engine class. After I moved it from WeatherWatchFaceService to Engine, the watch side received what I was trying to send from the mobile.

Cheers.