Request - Response API for Android Wear 2.0?

Question

How do I implement a request-response protocol for an Android Wear 2.0 app?

Scenario:

When I tap on a button on the watch, I want it to fetch some data from the phone and display it on the watch's screen.

What I tried:

I implemented a working example using the MessageApi , but I don't like it. I send a dummy "request" in one place using one method, I disregard the PendingResult and then hope that eventually I will receive a message that will be a corresponding response.

Ideally, what I'd like to have is:

byte[] responseBytes = sendRequest(someRequestBytes);

Answer 1

I'm not sure what you have tried.

But this code should work to send a byte array.

Wearable.MessageApi.sendMessage(googleApiClient, transcriptionNodeId,
            VOICE_TRANSCRIPTION_MESSAGE_PATH, voiceData).setResultCallback(
                  new ResultCallback() {
                      @Override
                      public void onResult(SendMessageResult sendMessageResult) {
                          if (!sendMessageResult.getStatus().isSuccess()) {
                              // Failed to send message
                          }
                      }
                  }
            );

voiceData is a simple byte array. This array will be received by both wearable and handheld device.

https://developer.android.com/training/wearables/data-layer/messages.html

To retrieve the data use this:

@Override
public void onMessageReceived(MessageEvent messageEvent) {
    if (messageEvent.getPath().equals(YOUR_TEXT)) {
        messageEvent.getData();//this is your byte array
    }
}