override fun onDataChanged(dataEvents: DataEventBuffer?) {
 dataEvents?.let { events ->
   for (event in events) {
     when (event.dataItem.uri.path) {
        "/requestBalance" -> // proceed request
        "/requestweeklyBalance" -> // proceed request
        "/drinkEvent" -> {
           val dataItem = DataMapItem.fromDataItem(event.dataItem)
           val value = dataItem.dataMap.getDouble("drinkEventValue")
           val drinkId = dataItem.dataMap.getInt("drinkEventDrinkId")
     }
}