HeadsetConnectionReceiver.kt

class HeadsetConnectionReceiver(private val actionPlugged: (Boolean) -> Unit) : BroadcastReceiver() {
  override fun onReceive(context: Context?, intent: Intent?) {
    intent?.run {
      if (Intent.ACTION_HEADSET_PLUG == action) {
        when (getIntExtra("state", -1)) {
          0 -> actionPlugged(false)
          1 -> actionPlugged(true)
        }
      }
    }
  }
}