DemoWearActivity.java

package com.ToxicBakery.lollipop;

import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Handler;
import android.support.wearable.view.WatchViewStub;
import android.widget.ImageView;

import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.data.FreezableUtils;
import com.google.android.gms.wearable.Asset;
import com.google.android.gms.wearable.DataApi;
import com.google.android.gms.wearable.DataEvent;
import com.google.android.gms.wearable.DataEventBuffer;
import com.google.android.gms.wearable.DataMapItem;
import com.google.android.gms.wearable.Wearable;

import java.io.InputStream;
import java.util.List;

public class DemoWearActivity extends Activity implements GoogleApiClient.ConnectionCallbacks,
        GoogleApiClient.OnConnectionFailedListener, DataApi.DataListener {

    private static final String IMAGE_PATH = "/image";
    private static final String IMAGE_KEY = "photo";

    private ImageView imageView;
    private GoogleApiClient googleApiClient;
    private Handler handler;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_demo_wear);

        final WatchViewStub stub = (WatchViewStub) findViewById(R.id.watch_view_stub);
        stub.setOnLayoutInflatedListener(new WatchViewStub.OnLayoutInflatedListener() {
            @Override
            public void onLayoutInflated(WatchViewStub stub) {
                imageView = (ImageView) stub.findViewById(R.id.imageview);
            }
        });

        handler = new Handler();
        googleApiClient = new GoogleApiClient.Builder(this)
                .addApi(Wearable.API)
                .addConnectionCallbacks(this)
                .addOnConnectionFailedListener(this)
                .build();
    }

    @Override
    protected void onResume() {
        super.onResume();
        googleApiClient.connect();
    }

    @Override
    protected void onPause() {
        super.onPause();
        Wearable.DataApi.removeListener(googleApiClient, this);
        googleApiClient.disconnect();
    }

    @Override
    public void onConnected(Bundle bundle) {
        Wearable.DataApi.addListener(googleApiClient, this);
    }

    @Override
    public void onConnectionSuspended(int i) {

    }

    @Override
    public void onDataChanged(DataEventBuffer dataEvents) {
        final List<DataEvent> events = FreezableUtils.freezeIterable(dataEvents);
        dataEvents.close();
        for (DataEvent event : events) {
            if (event.getType() == DataEvent.TYPE_CHANGED) {
                String path = event.getDataItem().getUri().getPath();
                if (IMAGE_PATH.equals(path)) {
                    DataMapItem dataMapItem = DataMapItem.fromDataItem(event.getDataItem());
                    Asset photo = dataMapItem.getDataMap()
                            .getAsset(IMAGE_KEY);
                    final Bitmap bitmap = loadBitmapFromAsset(googleApiClient, photo);
                    handler.post(new Runnable() {
                        @Override
                        public void run() {
                            imageView.setImageBitmap(bitmap);
                        }
                    });

                }

            }
        }
    }

    @Override
    public void onConnectionFailed(ConnectionResult connectionResult) {

    }

    /**
     * Extracts {@link android.graphics.Bitmap} data from the {@link com.google.android.gms.wearable.Asset}
     */
    private Bitmap loadBitmapFromAsset(GoogleApiClient apiClient, Asset asset) {
        if (asset == null) {
            throw new IllegalArgumentException("Asset must be non-null");
        }

        InputStream assetInputStream = Wearable.DataApi.getFdForAsset(
                apiClient, asset).await().getInputStream();

        if (assetInputStream == null) {
            return null;
        }
        return BitmapFactory.decodeStream(assetInputStream);
    }
}