当应用程序位于前台时，FCM在oreo上没有通知（在oreo之下，它可以工作）

Question

我想在手机上接收FCM通知。我正在使用下面的代码。现在我的问题是，当我在android oreo上运行并且该应用程序在前台运行时，我没有收到消息（但是在android 7上，它可以正常工作！）。我必须进行哪些更改才能使其正常工作？后台以及该应用被终止时在两个操作系统上均可使用。

public class MyFirebaseMessagingService extends FirebaseMessagingService {

@Override
public void onMessageReceived(RemoteMessage remoteMessage) {
    super.onMessageReceived(remoteMessage);

    //if the message contains data payload
    //It is a map of custom keyvalues
    //we can read it easily
    if(remoteMessage.getData() != null){

        sendNotification(remoteMessage);
    }

}

private void sendNotification(RemoteMessage remoteMessage) {
    Map<String, String> data = remoteMessage.getData();
    String title = remoteMessage.getNotification().getTitle();
    String body = remoteMessage.getNotification().getBody();

    NotificationManager notificationManager = (NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
    String NOTIFICATION_CHANNEL_ID = "TestID";

    if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){

        @SuppressLint("WrongConstant")
        NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_CHANNEL_ID, "Notification", NotificationManager.IMPORTANCE_HIGH);

        notificationChannel.setDescription("Description");
        notificationChannel.enableLights(true);
        notificationChannel.setLightColor(Color.BLUE);
        notificationChannel.setVibrationPattern(new long[]{0,1000,500,1000});

    }

    NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(this,NOTIFICATION_CHANNEL_ID);

    notificationBuilder.setAutoCancel(true)
            .setDefaults(Notification.DEFAULT_ALL)
            .setWhen(System.currentTimeMillis())
            .setSmallIcon(R.drawable.app_icon)
            .setTicker("Ticker")
            .setContentTitle(title)
            .setContentText(body)
            .setContentInfo("info");

    notificationManager.notify(1,notificationBuilder.build());


}
}

谢谢！