Question

我正在构建一个应该接收Android android.intent.action.SCREEN_ON广播的应用，并在后台执行某些操作。

（该广播受到保护，无法添加到Manifest中的IntentFilter部分，需要通过registerReceiver()以编程方式注册）

我知道如何启动服务。我知道如何让它独立于启动它的Activity（所以它不会因此而死）。真正的问题是：

如何在服务中注册SCREEN_ON广播接收器，即使系统发送广播时由于RAM较低导致服务暂时被设备杀死，服务也会接收到它？

Answer 1

public class OnBootService extends Service {

   private static final String TAG = OnBootService.class.getSimpleName();
   private PowerButtonReceiver mPowerButtonReceiver = null;

   @Override
   public IBinder onBind(Intent intent) {
        return null;
   }

   @Override
   public int onStartCommand(final Intent intent, final int flags, final int startId) {

    if (mPowerButtonReceiver==null) {
        mPowerButtonReceiver = new PowerButtonReceiver();
        registerReceiver(mPowerButtonReceiver, new IntentFilter(Intent.ACTION_SCREEN_ON));
    }
    return Service.START_NOT_STICKY;
}

@Override
public void onCreate() {
    super.onCreate();

    Log.i(TAG,"onCreate()");
}

  // unregister the Receiver when the Service gets stopped (destroyed)
@Override
public void onDestroy() {
    super.onDestroy();

    unregisterReceiver(mPowerButtonReceiver);

    Log.i(TAG, ""+TAG+" stopped: "+ new Date().toString());
   }
}

编辑：我也添加了powerButtonReceiver：

public class PowerButtonReceiver extends BroadcastReceiver {

   private static final String TAG = "PowerButtonReceiver"; 

   private int mPowerClickCounter = 0;  
   private boolean inTime = true;

   @Override
   public void onReceive(Context context, Intent intent) {
       SharedPreferences sharedPref = context.getSharedPreferences("MyPrefs", Context.MODE_PRIVATE);

       Boolean bCheck = sharedPref.getBoolean("PowerButtonReceiverState", false);   

       // check if screen is on
       PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
       Boolean screenOn = pm.isScreenOn();
       Log.i(TAG, "Screen is on:  " + screenOn.toString());
 }}

运行将接收SCREEN_ON广播的服务

1 个答案: