FlutterTts flutterTts = new FlutterTts();
@override
  void initState() {
    // TODO: implement initState
    setList();
    _controller = ScrollController();
     flutterTts.setLanguage("en-US");
     flutterTts.setSpeechRate(0.7);
     flutterTts.setVolume(1.0);
     flutterTts.setPitch(1.0);
    super.initState();
  }
//calling this function on click
  _speak() async {
    setState(() {
      flutterTts.speak(alp[index].SpekingAlphabets);
    });
  }