package pandafang.demo.playerserver;
interface IRemoteService {void play();void stop();
}

/*** 播放音乐的服务*/
public class PlayerService extends Service {public static final String TAG = "PlayerService";private MediaPlayer mplayer;@Overridepublic IBinder onBind(Intent intent) {Log.i(TAG,"service onbind");if(mplayer==null){// 方法一说明// 此方法实例化播放器的同时指定音乐数据源 ,若用此方法在，mplayer.start() 之前不需再调用mplayer.prepare() // 官方文档有说明 ：On success, prepare() will already have been called and must not be called again.// 译文：一旦create成功，prepare已被调用，勿再调用 。查看源代码可知create方法内部已经调用prepare方法。// 方法一开始// mplayer = MediaPlayer.create(this, R.raw.lost);// 方法一结束// 方法二说明// 若用此方法，在mplayer.start() 之前需要调用mplayer.prepare() // 方法二开始mplayer = new MediaPlayer();try {FileDescriptor fd = getResources().openRawResourceFd(R.raw.lost).getFileDescriptor(); // 获取音乐数据源mplayer.setDataSource(fd); // 设置数据源mplayer.setLooping(true); // 设为循环播放} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}// 方法二结束Log.i(TAG,"player created");}return mBinder;}// 实现aidl文件中定义的接口private IBinder mBinder = new IRemoteService.Stub() {@Overridepublic void stop() throws RemoteException {try {if (mplayer.isPlaying()) {mplayer.stop();}} catch (Exception e) {// TODO: handle exceptione.printStackTrace();}}@Overridepublic void play() throws RemoteException {try {if (mplayer.isPlaying()) {return;}// start之前需要prepare。// 如果前面实例化mplayer时使用方法一，则第一次play的时候直接start，不用prepare。// 但是stop一次之后,再次play就需要在start之前prepare了。// 前面使用方法二 这里就简便了， 不用判断各种状况mplayer.prepare();mplayer.start();} catch (Exception e) {// TODO: handle exceptione.printStackTrace();}}};@Overridepublic boolean onUnbind(Intent intent) {if (mplayer != null) {mplayer.release();}Log.i(TAG,"service onUnbind");return super.onUnbind(intent);}}

　服务编写好以后，按照惯例在AndroidManifest.xml中加入声明，代码如下

<manifest xmlns:android="http://schemas.android.com/apk/res/android"package="pandafang.demo.playerserver"android:versionCode="1"android:versionName="1.0" ><uses-sdkandroid:minSdkVersion="8"android:targetSdkVersion="15" /><applicationandroid:icon="@drawable/ic_launcher"android:label="@string/app_name"android:theme="@style/AppTheme" ><service android:name=".PlayerService" android:process=":remote"><intent-filter ><action android:name="com.example.playerserver.PlayerService"/></intent-filter></service></application></manifest>

需要加入的只是<service>...</service>那段，要注意的是 android:process=":remote" 和 intent-filter 。

　　运行服务端到设备上，准备给客户端调用

客户端

　　新建一个android application project，命名为PlayerClient。将服务端放有aidl文件的包直接copy到客户

端src目录下，保留包中的aidl文件，其他删除。

　编写MainActivity.java 代码如下

/*** 客户端控制界面*/
public class MainActivity extends Activity {public static final String TAG = "MainActivity";// 服务端 AndroidManifest.xml中的intent-filter action声明的字符串public static final String ACTION = "com.example.playerserver.PlayerService";private Button playbtn, stopbtn;private IRemoteService mService;private boolean isBinded = false;private ServiceConnection conn = new ServiceConnection() {@Overridepublic void onServiceDisconnected(ComponentName name) {isBinded = false;mService = null;}@Overridepublic void onServiceConnected(ComponentName name, IBinder service) {mService = IRemoteService.Stub.asInterface(service);isBinded = true;}};@Overridepublic void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);doBind();initViews();}private void initViews() {playbtn = (Button) findViewById(R.id.button1);stopbtn = (Button) findViewById(R.id.button2);playbtn.setOnClickListener(clickListener);stopbtn.setOnClickListener(clickListener);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {getMenuInflater().inflate(R.menu.activity_main, menu);return true;}@Overrideprotected void onDestroy() {doUnbind();super.onDestroy();}public void doBind() {Intent intent = new Intent(ACTION);bindService(intent, conn, Context.BIND_AUTO_CREATE);}public void doUnbind() {if (isBinded) {unbindService(conn);mService = null;isBinded = false;}}private OnClickListener clickListener = new OnClickListener() {@Overridepublic void onClick(View v) {if (v.getId() == playbtn.getId()) {// playLog.i(TAG,"play button clicked");try {mService.play();} catch (RemoteException e) {// TODO Auto-generated catch blocke.printStackTrace();}} else {// stopLog.i(TAG,"stop button clicked");try {mService.stop();} catch (RemoteException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}};}

MainActivity是根据向导自动生成的，不需要在AndroidManifest.xml中注册声明了

　　运行客户端到设备，按下按钮可以播放/停止 效果如图