Firebase app背景或杀死notfication

Question

我正在编写Firebase应用程序，以便在我的应用程序的值（数字）为红色时发送通知。当应用程序在后台运行或被杀时，我尝试发送消息，但我的程序不起作用，我不知道如何调用onMessageReceived()方法。

Station1.java

public class Station1 extends AppCompatActivity implements getData.ReturnValue {

private MyFirebaseMessagingService FBMessagingService = null;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
      //widget id 
  }

        if (mpxInt < mpxIntMin || mpxInt > mpxIntMax) {
            Mpx.setText(valeurs.getMpx());//affiche la valeur mpx dans le textView
            Mpx.setTextColor(Color.parseColor("#DF0101"));//red
            FBMessagingService.onMessageReceived(RemoteMessage);//?
        } else {
            Mpx.setText(valeurs.getMpx());
        }

}

MyFirebaseMessagingService.java

 public class MyFirebaseMessagingService extends FirebaseMessagingService {

    public void onMessageReceived(RemoteMessage remoteMessage) {
    Map<String, String> data = remoteMessage.getData();

    //you can get your text message here.
    String text= data.get("text");

    Intent i =new Intent(this,Station1.class);
    i.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

    PendingIntent pendingIntent = PendingIntent.getActivity(this,0,i,PendingIntent.FLAG_ONE_SHOT);


    NotificationCompat.Builder notificationBuilder=new 
    NotificationCompat.Builder(this);
    notificationBuilder.setContentTitle("FCM NOTIFICATION");
    notificationBuilder.setContentText(remoteMessage.getNotification().getBody());

    notificationBuilder.setAutoCancel(true);
    notificationBuilder.setSmallIcon(R.mipmap.ic_launcher);
    notificationBuilder.setContentIntent(pendingIntent);
    NotificationManager notidicationManager= (NotificationManager) 

    getSystemService(Context.NOTIFICATION_SERVICE);
    notidicationManager.notify(0,notificationBuilder.build());


    }
}