PROSAGA码农传奇-安卓-调用onMessageRecieved（），执行其代码但不显示通知

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  <P>
    对于Android 8及更高版本，请使用下面的通知渠道
  </p>
   <pre>
    <code>
      Intent intent=new Intent(this, WelcomeActivity.class);
            intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            PendingIntent pendingIntent=PendingIntent.getActivity(this
                    ,0
                    ,intent
                    ,PendingIntent.FLAG_ONE_SHOT);
            NotificationCompat.Builder notificationBuilder=new NotificationCompat.Builder(this);
            notificationBuilder.setContentTitle(getString(R.string.app_name));
            notificationBuilder.setContentText(message);
            Uri soundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
            notificationBuilder.setSound(soundUri);
            notificationBuilder.setSmallIcon(R.mipmap.ic_launcher);
            notificationBuilder.setLargeIcon(BitmapFactory.decodeResource(this.getResources(),R.mipmap.ic_launcher));
            notificationBuilder.setAutoCancel(true);
            Vibrator v=(Vibrator) this.getSystemService(Context.VIBRATOR_SERVICE);
            v.vibrate(1000);
            notificationBuilder.setContentIntent(pendingIntent);

NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

// Since android Oreo notification channel is needed.
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
           /* NotificationChannel channel = new NotificationChannel(channelId,
                    "Membership Alerts",
                    NotificationManager.IMPORTANCE_DEFAULT);
            notificationManager.createNotificationChannel(channel);*/

CharSequence name = getString(R.string.notification_channel_name);
            String description = getString(R.string.notification_channel_description);
            int importance = NotificationManager.IMPORTANCE_DEFAULT;
            NotificationChannel channel = new NotificationChannel(channelId, name, importance);
            channel.setDescription(description);
            notificationManager.createNotificationChannel(channel);
        }

notificationManager.notify(0 /* ID of notification */, notificationBuilder.build());

</code>
  </pre>
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