为您的所有活动制作一个 BaseActivity。在 BaseActivity 中,执行以下操作:
public class MyActivity extends Activity implements ServiceConnection {
    //you may add @override, it's optional
    protected void onStart() {
        super.onStart();
        Intent intent = new Intent(this, MyService.class);
        bindService(intent, this, 0);
    }
    //you may add @override, it's optional
    protected void onStop() {
        super.onStop();
        unbindService(this);
    }
    public void onServiceConnected(ComponentName name, IBinder binder) {};
    public void onServiceDisconnected(ComponentName name) {};
    /* lots of other stuff ... */
}
您的 BaseActivity 将需要实现 ServiceConnection 接口(或者您可以使用匿名内部类),但您可以将这些方法留空。
在您的 Service 类中,您需要实现该onBind(Intent)方法并返回一个 IBinder。最简单的方法是这样的:
public class MyService extends Service {
    private final IBinder localBinder = new LocalBinder();
    public void onCreate() {
        super.onCreate();
        // first time the service is bound, it will be created
        // you can start up your timed-operations here
    }
    public IBinder onBind(Intent intent) {
        return localBinder;
    }
    public void onUnbind(Intent intent) {
        // called when the last Activity is unbound from this service
        // stop your timed operations here
    }
    public class LocalBinder extends Binder {
        MyService getService() {
            return MyService.this;
        }
    }
}