public class MainActivity extends Activity {      @Override    protected void onCreate(Bundle savedInstanceState) {      super.onCreate(savedInstanceState);      setContentView(R.layout.activity_main);    }      public void startService(View source) {      // 創(chuàng)建所需要啟動的Service的Intent      Intent intent = new Intent(this, MyService.class);      startService(intent);    }      public void startIntentService(View source) {      // 創(chuàng)建需要啟動的IntentService的Intent      Intent intent = new Intent(this, MyIntentService.class);      startService(intent);    }  }  

public class MyIntentService extends IntentService {      public MyIntentService() {      super("MyIntentService");    }      @Override    protected void onHandleIntent(Intent intent) {      // IntentService會使用單獨(dú)的線程來執(zhí)行該方法的代碼      // 該方法內(nèi)執(zhí)行耗時任務(wù)，比如下載文件，此處只是讓線程等待20秒      long endTime = System.currentTimeMillis() + 20 * 1000;      System.out.println("onStart");      while (System.currentTimeMillis() < endTime) {        synchronized (this) {          try {            wait(endTime - System.currentTimeMillis());          } catch (InterruptedException e) {            e.printStackTrace();          }        }      }      System.out.println("----耗時任務(wù)執(zhí)行完成---");    }  }   

public class MyService extends Service {      @Override    public IBinder onBind(Intent arg0) {      return null;    }      @Override    public int onStartCommand(Intent intent, int flags, int startId) {      // 該方法內(nèi)執(zhí)行耗時任務(wù)可能導(dǎo)致ANR(Application Not Responding)異常      long endTime = System.currentTimeMillis() + 20 * 1000;      System.out.println("onStart");      while (System.currentTimeMillis() < endTime) {        synchronized (this) {          try {            wait(endTime - System.currentTimeMillis());          } catch (InterruptedException e) {            e.printStackTrace();          }        }      }      System.out.println("----耗時任務(wù)執(zhí)行完成---");      return START_STICKY;    }  }