AIDL(AndRoid接口描述语言)是一种借口描述语言; 编译器可以通过aidl文件生成一段代码，通过预先定义的接口达到两个进程内部通信进程的目的. 如果需要在一个Activity中, 访问另一个Service中的某个对象, 需要先将对象转化成AIDL可识别的参数(可能是多个参数), 然后使用AIDL来传递这些参数, 在消息的接收端, 使用这些参数组装成自己需要的对象.
1.定义：src/package/IPlayer.aidl文件。
如：
package com.chonwhite.mplayer; //--要有包的全称。 interface IPlayer{ void play(); void pause(); void stop(); int getDuration(); int getCurrentTime(); void setCurrent(int cur); boolean isPlaying(); }
2.定义Service 服务
public class LocalService extends Service { private NotificationManager mNM; private MediaPlayer mPlayer; IPlayer.Stub stub = new IPlayer.Stub() { public void play() throws RemoteException { mPlayer.start(); } public void pause() throws RemoteException { mPlayer.pause(); } public void stop() throws RemoteException { mPlayer.stop(); } public int getDuration() throws RemoteException { return mPlayer.getDuration(); } public int getCurrentTime() throws RemoteException { return mPlayer.getCurrentPosition(); } public void setCurrent(int cur) throws RemoteException { mPlayer.seekTo(cur); } public boolean isPlaying() throws RemoteException { return mPlayer.isPlaying(); } }; @Override public void onCreate() { mNM = (NotificationManager)getSystemService(NOTIFICATION_SERVICE); mPlayer = MediaPlayer.create(this, R.raw.fly); mPlayer.start(); showNotification(); } @Override public int onStartCommand(Intent intent, int flags, int startId) { Log.i("LocalService", "Received start id " + startId + ": " + intent); // We want this service to continue running until it is explicitly // stopped, so return sticky. return START_STICKY; } @Override public void onDestroy() { // Cancel the persistent notification. mNM.cancel("ServiceStarted", 0); // Tell the user we stopped. Toast.makeText(this, "ServiceStoped", Toast.LENGTH_SHORT).show(); } @Override public IBinder onBind(Intent intent) { return stub; } @Override public boolean onUnbind(Intent intent) { return super.onUnbind(intent); } /** * Show a notification while this service is running. */ private void showNotification() { // In this sample, we'll use the same text for the ticker and the expanded notification CharSequence text = "LocalServiceStarted"; // Set the icon, scrolling text and timestamp Notification notification = new Notification(R.drawable.icon, text, System.currentTimeMillis()); // The PendingIntent to launch our activity if the user selects this notification PendingIntent contentIntent = PendingIntent.getActivity(this, 0, new Intent(this, Main.class), 0); // Set the info for the views that show in the notification panel. notification.setLatestEventInfo(this, "ServiceLable", text, contentIntent); // Send the notification. // We use a layout id because it is a unique number. We use it later to cancel. mNM.notify("LocalServiceStarted", 0, notification); } }
3.调用Service
@Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main);
bindService(new Intent(Main.this, LocalService.class), mConnection, Context.BIND_AUTO_CREATE);
}
void doUnbindService() { unbindService(mConnection); } @Override protected void onDestroy() { super.onDestroy(); doUnbindService(); }
private ServiceConnection mConnection = new ServiceConnection() { public void onServiceConnected(ComponentName className, IBinder service) { mPlayer = IPlayer.Stub.asInterface(service); // Tell the user about this for our demo. Toast.makeText(Main.this, getString(R.string.serviceconnected), Toast.LENGTH_SHORT).show(); } public void onServiceDisconnected(ComponentName className) { mPlayer = null; Toast.makeText(Main.this, getString(R.string.serviedisconnected), Toast.LENGTH_SHORT).show(); }; };
4:Android.mk
添加：
LOCAL_SRC_FILES := $(call all-java-files-under, src) / src/com/chonwhite/mplayer/IPlayer.aidl
