我正在使用FCM API与邮递员发送通知,这是通知结构：

{ "notification": {
      "title": "Notification title","body": "Notification message","sound": "default","color": "#53c4bc","click_action": "MY_BOOK","icon": "ic_launcher"
   },"data": {
       "main_picture": "URL_OF_THE_IMAGE"  
   },"to" : "USER_FCM_TOKEN"
}

要渲染的图像取自data.main_picture.

我已经实现了我自己的FirebaseMessagingService,它使通知在前台状态下完美显示.通知代码是下一个：

NotificationCompat.BigPictureStyle notiStyle = new NotificationCompat.BigPictureStyle();
notiStyle.setSummaryText(messageBody);
notiStyle.bigPicture(picture);
 
Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
 
NotificationCompat.Builder notificationBuilder = (NotificationCompat.Builder) new NotificationCompat.Builder(this)
            .setSmallIcon(R.drawable.ic_launcher)
            .setLargeIcon(bigIcon)
            .setContentTitle(title)
            .setContentText(messageBody)
            .setAutoCancel(true)
            .setSound(defaultSoundUri)
            .setContentIntent(pendingIntent)
            .setStyle(notiStyle); code here
 
NotificationManager notificationManager =
            (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
notificationManager.notify(0,notificationBuilder.build());

但是,在后台,服务甚至不执行.在AndroidManifest.xml中,Firebase服务的声明如下：

<service
    android:name=".MyFirebaseMessagingService">
  <intent-filter>
    <action android:name="com.google.firebase.MESSAGING_EVENT"/>
  </intent-filter>
</service>
 
<service
    android:name=".MyFirebaseInstanceIDService">
  <intent-filter>
    <action android:name="com.google.firebase.INSTANCE_ID_EVENT"/>
  </intent-filter>
</service>

我的问题不是LargeIcon或SmallIcon,而是显示大图.

感谢您的支持.