FCM 푸시 헤드업 알림 안뜨는 경우 ( 포어그라운드 상태 )

// foreground 상태에서 해드업 알림
    private void sendNotification2(String title, String body, Intent intent) {

        NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
        String NOTIFICATION_CHANNEL_ID = "fore001";

        if (intent == null)
            intent = Intent.makeRestartActivityTask(new ComponentName(this, SplashActivity.class));
        PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_ONE_SHOT);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_CHANNEL_ID, "푸시 알림", NotificationManager.IMPORTANCE_HIGH);

            // Configure the notification channel.
            notificationChannel.setDescription("Channel description");
            notificationChannel.enableLights(true);
            notificationChannel.setLightColor(Color.RED);
            notificationChannel.setVibrationPattern(new long[]{0, 1000});
            notificationChannel.enableVibration(true);
            notificationManager.createNotificationChannel(notificationChannel);
        }


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

        notificationBuilder.setAutoCancel(true)
                .setDefaults(Notification.DEFAULT_ALL)
                .setWhen(System.currentTimeMillis())
                .setSmallIcon(R.mipmap.ic_launcher)
                .setTicker("TICKER")
                .setPriority(NotificationManager.IMPORTANCE_HIGH)
                .setContentIntent(pendingIntent)
                .setContentTitle(title)
                .setContentText(body);
                //.setContentInfo("Info");
        notificationManager.notify(/*notification id*/1, notificationBuilder.build());
    }

* 채널 아이디를 디폴트 채널아이디와 동일하게 설정하면 해드업이 나타나지 않음.