Question

我有一个应该显示推送通知的应用，但它没有此行new NotificationCompat.Builder(this);在代码中被取消。我是新手，这怎么可行这是FirebaseMessagingService.java类中的代码

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

    sendNotification(remoteMessage.getNotification().getBody());
}

private void sendNotification(String MessageBody){
 Intent intent= new Intent(this,MainActivity.class);
 intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

    PendingIntent pendingIntent=PendingIntent.getActivity(this,0,intent,PendingIntent.FLAG_ONE_SHOT);
    Uri defaultSoundUri= RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
    NotificationCompat.Builder notificationBuilder=new NotificationCompat.Builder(this);
   notificationBuilder.setSmallIcon(R.drawable.ic_launcher_background);
    notificationBuilder.setContentTitle("Hope");
     notificationBuilder.setContentText(MessageBody);
   notificationBuilder.setAutoCancel(true);
   notificationBuilder.setSound(defaultSoundUri);
  notificationBuilder.setContentIntent(pendingIntent);
  NotificationManager notificationManager=(NotificationManager)getSystemService(Context.NOTIFICATION_SERVICE);
  notificationManager.notify(0,notificationBuilder.build());

}

}

Answer 1

尝试使用：

NotificationChannel mChannel = new NotificationChannel("", "", 1);
notificationManager.createNotificationChannel(mChannel);

Answer 2

这似乎是here的重复问题。

由于 Android O （表示您的targetSdk为26或更高），如果没有notification channel，通知就不会显示。

这是我的工作代码：）

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

Uri defaultSoundUri = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);

// The id of the channel.
final String CHANNEL_ID = "default";
// The user-visible name of the channel.
final String CHANNEL_NAME = "Default";
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.O) {
    NotificationChannel defaultChannel = new NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_HIGH);
    notificationManager.createNotificationChannel(defaultChannel);
}

intent.setFlags(FLAG_ACTIVITY_NEW_TASK | FLAG_ACTIVITY_CLEAR_TOP);
PendingIntent pendingIntent = PendingIntent.getActivity(c, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);

final NotificationCompat.Builder notificationBuilder = new NotificationCompat.Builder(c, CHANNEL_ID)
        .setLargeIcon(your_custom_bitmap)
        .setSmallIcon(R.drawable.ic_notification)
        .setColor(ContextCompat.getColor(c, R.color.notification))
        .setContentTitle(getString(R.string.app_name))
        .setContentText(message)
        .setWhen(System.currentTimeMillis())
        .setSound(defaultSoundUri)
        .setDefaults(Notification.DEFAULT_SOUND | Notification.DEFAULT_VIBRATE)
        .setLights(ContextCompat.getColor(c, R.color.colorAccentLight), 5000, 5000)
        .setAutoCancel(true)
        .setPriority(NotificationCompat.PRIORITY_MAX)
        .setContentIntent(pendingIntent);

notificationManager.notify("myapp", 0, notificationBuilder.build());

Answer 3

如果您从Firebase控制台推送通知，则只有在应用程序处于后台或未运行时才会显示通知。您可以在HERE了解更多信息。如果要接收onMessageReceived（）方法的通知数据，则必须从后端发送通知

通知不显示firebase Android 8

3 个答案: