Android 多進程通信之Messenger

多進程通信有：ContentProvider、廣播、文件、SharedPreferences、AIDL。
Messenger能實現多進程通信是因爲Messenger底層就是AIDL實現的。
主進程MainActivity:

public class MainActivity extends AppCompatActivity {
    private boolean isConnect = false;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Intent intent = new Intent(this,MyService.class);
        bindService(intent,connection,BIND_AUTO_CREATE);
        findViewById(R.id.tv).setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Message msg = Message.obtain(null,1);
                Bundle bundle = new Bundle();
                bundle.putString("data","來自主進程信息");
                msg.setData(bundle);
                msg.replyTo = mMessenger;
                try {
                    if (isConnect)
                        serviceMsg.send(msg);
                } catch (RemoteException e) {
                    e.printStackTrace();
                }
            }
        });
    }
    private Messenger serviceMsg;
    private ServiceConnection connection = new ServiceConnection() {
        @Override
        public void onServiceConnected(ComponentName name, IBinder service) {
            serviceMsg = new Messenger(service);
            isConnect = true;
        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            isConnect = false;
        }
    };

    private Messenger mMessenger = new Messenger(new Handler() {
        @Override
        public void handleMessage(Message msg){
            Log.e("Activity",""+msg.getData().getString("data"));
        }
    });

    @Override
    protected void onDestroy() {
        super.onDestroy();
        unbindService(connection);
    }
}

remote進程的service：

public class MyService extends Service{
    private final Messenger messenger = new Messenger(new Handler(){
        @Override
        public void handleMessage(Message msg) {
            if (msg.what == 1) {
                Log.e("Service",""+msg.getData().getString("data"));
            }
            try {
                Thread.sleep(2000);
                Bundle bundle = new Bundle();
                bundle.putString("data","來自service的信息");
                msg.setData(bundle);
                msg.replyTo.send(msg);
            } catch (InterruptedException e) {
                e.printStackTrace();
            } catch (RemoteException e) {
                e.printStackTrace();
            }
        }
    });

    @Nullable
    @Override
    public IBinder onBind(Intent intent) {
        return messenger.getBinder();
    }
}

AndroidManifest：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.flk.ipc">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <service android:name=".MyService"
            android:process=":remote"/>
    </application>

</manifest>