This expression has a type of 'void' so its value can't be used. Try checking to see if you're using the correct API; there might be a function or call that returns void you didn't expect. Also check type parameters and variables which might also be void.

[fanydhilah]

hello, i am new in this flutter, and i wanna make chatbot app with stt and tts inside it. but i got error in this and i don;t khow what todo, please help me

`class _MyApppState extends State {
stt.SpeechToText _speech;
bool _isListening = false;
String _text = "";
String speak;
String qry;

@OverRide
void initState() {
super.initState();
_speech = stt.SpeechToText();
}

final FlutterTts flutterTts = FlutterTts();

void response(query) async {
AuthGoogle authGoogle =
await AuthGoogle(fileJson: "assets/newagent-kalbgl-c0fb323bfb4c.json")
.build();
Dialogflow dialogflow =
Dialogflow(authGoogle: authGoogle, language: Language.indonesian);
AIResponse aiResponse = await dialogflow.detectIntent(query);
setState(() {
messsages.insert(0, {
"data": 0,
"message": aiResponse.getListMessage()[0]["text"]["text"][0].toString()
});
});

print(aiResponse.getListMessage()[0]["text"]["text"][0].toString());

}

void _speak(query) async {
print(await flutterTts.getLanguages);
await flutterTts.setLanguage('jv-ID');
await flutterTts.speak(query);
}

final messageInsert = TextEditingController();
List messsages = List();

@OverRide
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(
"Jawa Bot",
),
backgroundColor: Colors.blueGrey,
),
body: Container(
child: Column(children: [
Center(
child: Container(
padding: EdgeInsets.only(top: 15, bottom: 10),
child: Text(
"Dinten Niki, ${DateFormat("Hm").format(DateTime.now())}",
style: TextStyle(fontSize: 15),
),
),
),
Flexible(
child: ListView.builder(
reverse: true,
padding: EdgeInsets.all(10.0),
itemCount: messsages.length,
itemBuilder: (context, index) => chat(
messsages[index]["message"].toString(),
messsages[index]["data"]))),
SizedBox(
height: 20,
),
Divider(
height: 5.0,
color: Colors.greenAccent,
),
Container(
child: ListTile(
leading: IconButton(
icon: Icon(
_isListening ? Icons.mic : Icons.mic_none,
color: Colors.greenAccent,
size: 35,
),
onPressed: () {
_listen();
if (_text.isEmpty) {
print("empty message");
} else {
setState(() {
messsages.insert(0, {"data": 1, "message": _text});
});
speak = response(_text);
_speak(speak);
_text = '';
}
FocusScopeNode currentFocus = FocusScope.of(context);
if (!currentFocus.hasPrimaryFocus) {
currentFocus.unfocus();
}
},
),
title: Container(
decoration: BoxDecoration(
borderRadius: BorderRadius.all(Radius.circular(15)),
color: Color.fromRGBO(220, 220, 220, 1)),
padding: EdgeInsets.only(left: 15),
child: Row(
children: [
Flexible(
child: TextField(
controller: messageInsert,
decoration: InputDecoration(
hintText: "Send Your Message",
hintStyle: TextStyle(color: Colors.black26),
border: InputBorder.none,
focusedBorder: InputBorder.none,
enabledBorder: InputBorder.none,
errorBorder: InputBorder.none,
disabledBorder: InputBorder.none,
),
style: TextStyle(fontSize: 16, color: Colors.black),
)),
],
),
),
trailing: IconButton(
icon: Icon(Icons.send, size: 30, color: Colors.greenAccent),
onPressed: () {
if (messageInsert.text.isEmpty) {
print("empty message");
} else {
setState(() {
messsages.insert(
0, {"data": 1, "message": messageInsert.text});
});
response(messageInsert.text);
_speak(messageInsert.text);
messageInsert.clear();
}
FocusScopeNode currentFocus = FocusScope.of(context);
if (!currentFocus.hasPrimaryFocus) {
currentFocus.unfocus();
}
}),
)),
SizedBox(
height: 15.0,
)
]),
));
}`

i wanna use tts for this text

`oid response(query) async {
AuthGoogle authGoogle =
await AuthGoogle(fileJson: "assets/newagent-kalbgl-c0fb323bfb4c.json")
.build();
Dialogflow dialogflow =
Dialogflow(authGoogle: authGoogle, language: Language.indonesian);
AIResponse aiResponse = await dialogflow.detectIntent(query);
setState(() {
messsages.insert(0, {
"data": 0,
"message": aiResponse.getListMessage()[0]["text"]["text"][0].toString()
});
});

print(aiResponse.getListMessage()[0]["text"]["text"][0].toString());

}

void _speak(query) async {
print(await flutterTts.getLanguages);
await flutterTts.setLanguage('jv-ID');
await flutterTts.speak(query);
}
`

and i put it like this

onPressed: () { _listen(); if (_text.isEmpty) { print("empty message"); } else { setState(() { messsages.insert(0, {"data": 1, "message": _text}); }); speak = response(_text); _speak(speak); _text = ''; } FocusScopeNode currentFocus = FocusScope.of(context); if (!currentFocus.hasPrimaryFocus) { currentFocus.unfocus(); } },

i don't know how to fix this, please help me, thankyou