从Android 8.0(API级别26)开始，通知需要一个通知渠道.您需要为通知创建并附加一个通知渠道.

Starting in Android 8.0 (API level 26), notifications require a notification channel. You need to create and attach a notification channel for your notification.

private fun initChannel(channelId: String, channelName: String) {
        if (Build.VERSION.SDK_INT < 26) {
            return
        }
        val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        val channel = NotificationChannel(channelId, channelName, NotificationManager.IMPORTANCE_DEFAULT)

        notificationManager.createNotificationChannel(channel)
    }

然后

private fun startTripNotification() {

        initChannel(NOTIFICATION_CHANNEL_ID, NOTIFICATION_CHANNEL_NAME)

        val pendingIntent = PendingIntent.getActivity(activity, 0, Intent(), 0)
        val     notification = NotificationCompat.Builder(activity,NOTIFICATION_CHANNEL_ID)
            .setContentTitle("test notification title")
            .setContentText("test notification text")
            .setSmallIcon(R.mipmap.ic_main_icon_round)
            .setLargeIcon(BitmapFactory.decodeResource(this.resources, R.mipmap.ic_launcher))
        notification.setContentIntent(pendingIntent)
        val notificationManager = activity?.getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
        notificationManager.notify(0, notification.build())
    }

您可以在此处