android 將Service綁定到Activity

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Service可以和Activity綁定，後者會維持對Service執行個體的引用，此引用允許你像對待其他執行個體化的那樣，對正在啟動並執行Service進行方法調用。

允許Service和Activity綁定，這樣能夠獲得更加詳細的介面。要讓一個Service支援綁定，需要實現onBind方法，並返回被綁定Service的當前執行個體。

package com.example.androidtest.service;import android.app.Service;import android.content.Intent;import android.os.Binder;import android.os.IBinder;public class MyService extends Service {private final IBinder binder = new MyBinder();@Overridepublic IBinder onBind(Intent intent) {// TODO Auto-generated method stubreturn  binder;}public class MyBinder extends Binder{MyService getService(){return MyService.this;}}@Overridepublic void onCreate() {// TODO Auto-generated method stubsuper.onCreate();}}

Service和其他組件之間的串連表示為一個ServiceConnection.

要想將一個Service和其他組件進行綁定，需要實現一個新的ServiceConnection，建立一個串連之後，就可以通過重寫onServiceConnected和onServiceDisconnectd方法來獲得對service的引用。程式：

package com.example.androidtest;import com.example.androidtest.service.MyService;import android.os.Bundle;import android.os.IBinder;import android.app.Activity;import android.content.ComponentName;import android.content.Intent;import android.content.ServiceConnection;import android.view.Menu;public class MainActivity extends Activity {private MyService myService;//service和activity之間的串連private ServiceConnection mConnection = new ServiceConnection() {@Overridepublic void onServiceDisconnected(ComponentName arg0) {// TODO Auto-generated method stubmyService = null;}@Overridepublic void onServiceConnected(ComponentName className, IBinder service) {//當建立串連時調用myService = ((MyService.MyBinder)service).getService();}};public void toBind(){//綁定一個serviceIntent bindIntent = new Intent(MainActivity.this,MyService.class);bindService(bindIntent, mConnection, BIND_AUTO_CREATE);}@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);}@Overridepublic boolean onCreateOptionsMenu(Menu menu) {// Inflate the menu; this adds items to the action bar if it is present.getMenuInflater().inflate(R.menu.main, menu);return true;}}