从可穿戴设备向 phone 发送消息，然后立即回复

Send message from wearable to phone and then immediately reply

我今天一整天都在与 Android 佩戴消息 API 作斗争，终于接受了我需要一些帮助。

我的应用程序非常简单。移动部分由一个 MainActivity（除了显示 "Hello world" 和一个扩展 WearableListenerService 的服务组成。Wear 部分只是一个带有单个按钮的 MainActivity，并实现 MessageApi.MessageListener.

想法很简单：按下 Wear 设备上的按钮，向移动设备发送消息。当 Mobile 收到消息时，它会显示一个 Toast，其中包含发件人的 消息路径 （例如 /mobile）。执行此操作后，移动设备应立即使用我的 reply()[=39= 向 Wear 设备发送一条消息 back ] 方法。我想做的就是记录这条消息。

我可以完美地完成第一部分。按下 Button 时，Mobile 会弹出一个 Toast，上面写着“/mobile”。然而，答复似乎只是迷失在以太中。没有错误，但也没有消息。

有人可以帮我理解我做错了什么吗？我在下面粘贴了我的文件。

This 是我正在关注的教程。干杯！

穿：MainActivity.java

package org.thecosmicfrog.toastdroidmessageapitutorial;

import android.app.Activity;
import android.content.Context;
import android.os.Bundle;
import android.support.wearable.view.WatchViewStub;
import android.util.Log;
import android.view.View;

import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.wearable.MessageApi;
import com.google.android.gms.wearable.MessageEvent;
import com.google.android.gms.wearable.Node;
import com.google.android.gms.wearable.NodeApi;
import com.google.android.gms.wearable.Wearable;

import java.util.List;
import java.util.concurrent.TimeUnit;

public class MainActivity extends Activity implements MessageApi.MessageListener {

    private final String LOG_TAG = MainActivity.class.getSimpleName();

    private static final long CONNECTION_TIME_OUT_MS = 100;
    private static final String MOBILE_PATH = "/mobile";

    private GoogleApiClient googleApiClient;
    private String nodeId;

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

        initGoogleApiClient();

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

    private void initGoogleApiClient() {
        googleApiClient = getGoogleApiClient(this);
        retrieveDeviceNode();
    }

    private GoogleApiClient getGoogleApiClient(Context context) {
        return new GoogleApiClient.Builder(context)
                .addApi(Wearable.API)
                .build();
    }

    private void retrieveDeviceNode() {
        new Thread(new Runnable() {
            @Override
            public void run() {
                if (googleApiClient != null && !(googleApiClient.isConnected() || googleApiClient.isConnecting()))
                    googleApiClient.blockingConnect(CONNECTION_TIME_OUT_MS, TimeUnit.MILLISECONDS);

                NodeApi.GetConnectedNodesResult result =
                        Wearable.NodeApi.getConnectedNodes(googleApiClient).await();

                List<Node> nodes = result.getNodes();

                if (nodes.size() > 0)
                    nodeId = nodes.get(0).getId();

                Log.v(LOG_TAG, "Node ID of phone: " + nodeId);

                googleApiClient.disconnect();
            }
        }).start();
    }

    private void initWidgets() {
        findViewById(R.id.button_toast).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                sendToast();
            }
        });
    }

    private void sendToast() {
        if (nodeId != null) {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    if (googleApiClient != null && !(googleApiClient.isConnected() || googleApiClient.isConnecting()))
                        googleApiClient.blockingConnect(CONNECTION_TIME_OUT_MS, TimeUnit.MILLISECONDS);

                    Wearable.MessageApi.sendMessage(googleApiClient, nodeId, MOBILE_PATH, null).await();
                    googleApiClient.disconnect();
                }
            }).start();
        }
    }

    @Override
    public void onMessageReceived(MessageEvent messageEvent) {
        Log.v(LOG_TAG, "In onMessageReceived()");

        if (messageEvent.getPath().equals("/wear")) {
            Log.v(LOG_TAG, "Success!");
        }
    }
}

手机：ListenerService.java

package org.thecosmicfrog.toastdroidmessageapitutorial;

import android.util.Log;
import android.widget.Toast;

import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.wearable.MessageEvent;
import com.google.android.gms.wearable.Wearable;
import com.google.android.gms.wearable.WearableListenerService;

import java.util.concurrent.TimeUnit;

public class ListenerService extends WearableListenerService {

    private final String LOG_TAG = ListenerService.class.getSimpleName();

    private static GoogleApiClient googleApiClient;

    private static final long CONNECTION_TIME_OUT_MS = 100;
    private static final String WEAR_PATH = "/wear";
    private String nodeId;

    @Override
    public void onMessageReceived(MessageEvent messageEvent) {
        if (messageEvent.getPath().equals("/mobile")) {
            nodeId = messageEvent.getSourceNodeId();
            Log.v(LOG_TAG, "Node ID of watch: " + nodeId);
            showToast(messageEvent.getPath());

            reply(WEAR_PATH);
        }
    }

    private void showToast(String message) {
        Toast.makeText(this, message, Toast.LENGTH_LONG).show();
    }

    private void reply(final String path) {
        googleApiClient = new GoogleApiClient.Builder(getApplicationContext())
                .addApi(Wearable.API)
                .build();

        Log.v(LOG_TAG, "In reply()");
        Log.v(LOG_TAG, "Path: " + path);

        if (googleApiClient != null && !(googleApiClient.isConnected() || googleApiClient.isConnecting()))
            googleApiClient.blockingConnect(CONNECTION_TIME_OUT_MS, TimeUnit.MILLISECONDS);

        Wearable.MessageApi.sendMessage(googleApiClient, nodeId, path, null).await();
        googleApiClient.disconnect();
    }
}

Mobile MainActivity 非常简单，所以为了清楚起见，我将其省略。

当你的 activity 被销毁时，你永远不会调用 MessageApi.addListener() in your Wear activity so your MessageListener is never registered to receive messages. You should also call MessageApi.removeListener()。

注意：这两种方法都需要连接 GoogleApiClient。如果您在 activity 期间让 GoogleApiClient 打开而不是尝试在 onDestroy().

中连接/removeListener()/断开连接，这可能会使逻辑更容易