升级到 Android 8.1 后 startForeground 失败

在对不同的解决方案进行了一段时间的修补之后，我发现必须在Android 8.1及更高版本中创建一个通知通道.

private fun startForeground() {
    val channelId =
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                createNotificationChannel("my_service", "My Background Service")
            } else {
                // If earlier version channel ID is not used
                // https://developer.android.com/reference/android/support/v4/app/NotificationCompat.Builder.html#NotificationCompat.Builder(android.content.Context)
                ""
            }

    val notificationBuilder = NotificationCompat.Builder(this, channelId )
    val notification = notificationBuilder.setOngoing(true)
            .setSmallIcon(R.mipmap.ic_launcher)
            .setPriority(PRIORITY_MIN)
            .setCategory(Notification.CATEGORY_SERVICE)
            .build()
    startForeground(101, notification)
}

@RequiresApi(Build.VERSION_CODES.O)
private fun createNotificationChannel(channelId: String, channelName: String): String{
    val chan = NotificationChannel(channelId,
            channelName, NotificationManager.IMPORTANCE_NONE)
    chan.lightColor = Color.BLUE
    chan.lockscreenVisibility = Notification.VISIBILITY_PRIVATE
    val service = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager
    service.createNotificationChannel(chan)
    return channelId
}

据我所知，后台服务现在显示为普通通知，用户可以通过取消 Select 通知通道来 Select 不显示.

Update:

<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />