Dart Flutter

RXDart

/*
* Prints the items in the list with delay
*/
StreamSubscription<String> timerSubscription;
    List<String> iterable = ["2", "1", "x"];
    timerSubscription = Observable.fromIterable(timerText).concatMap((i) {
      return new Observable.timer(i, Duration(seconds: 1));
    }).listen((x) {
      print(x); //Prints "2" , 1 sec later then prints "1", 1 sec later prints "x"
      if (x == iterable[0]) {
      } else if (x == iterable[1]) {        
      } else if (x == iterable[2]) {        
      }    
    }, onError: (x) {
      timerSubscription?.cancel();
    }, onDone: () {
      timerSubscription?.cancel();
    });
    
    /**
    * Convert Multi-layered Object to Key value pairs Map Object
    */
    Map<String, dynamic> toMap(Map map, {String oldKey = ""}) {
        Map<String, dynamic> retVal = Map<String, dynamic>();

        map.forEach((key, value) {
          if (value != null) {
            if (value is int) {
              String newKey = oldKey + "[$key]";
              if (oldKey.isEmpty) {
                newKey = key;
              }
              retVal.putIfAbsent(newKey, () => value);
            } else if (value is String) {
              String newKey = oldKey + "[$key]";
              if (oldKey.isEmpty) {
                newKey = key;
              }
              retVal.putIfAbsent(newKey, () => value);
            } else if (value is Map) {
              String newKey = oldKey + "[$key]";
              if (oldKey.isEmpty) {
                newKey = key;
              }
              retVal.addAll(toMap(value, oldKey: newKey));
            } else if (value is List<Map>) {
              int index = 0;
              value.forEach((x) {
                String newKey = oldKey + "[$key]";
                if (oldKey.isEmpty) {
                  newKey = key;
                }
                retVal.addAll(toMap(x, oldKey: newKey + '[$index]'));
                index++;
              });
            }
          }
        });
        return retVal;
      }
      /**
      * To Use: 
      * 1. Convert Object to JSON String -> output needs to be Map<String, dynamic> object
      * 2. Pass the Map<String, dynamic> object to the toMap()
      * 3. 
      */