how to show api call data in mention in flutter - flutter

Question

String string = "";
Map<String, dynamic> jsonMap = {};
List<Map<String, dynamic>> data = [];
class Mentions extends StatefulWidget {
const Mentions({
Key? key,
this.width,
this.height,
}) : super(key: key);
final double? width;
final double? height;
#override
_MentionsState createState() => _MentionsState();
}
class _MentionsState extends State<Mentions> {
GlobalKey<FlutterMentionsState> key = GlobalKey<FlutterMentionsState>();
Future apicall() async {
http.Response response;
var url = "https://7J8Y54OD18-dsn.algolia.net/1/indexes/users";
response = await http.get(Uri.parse(url), headers: {
'X-Algolia-API-Key': '841e31106f80e21b89b0d2b9ec7cd561',
'X-Algolia-Application-Id': '7J8Y54OD18'
});
if (response.statusCode == 200) {
setState(() {
jsonMap = json.decode(response.body);
(jsonMap['hits'] as List).forEach((x) => {data.add(Map.from(x))});
});
} else {
string = "failed";
}
}
#override
void initState() {
apicall();
super.initState();
}
#override
Widget build(BuildContext context) {
return Portal(
child: Scaffold(
appBar: AppBar(
title: Text("flutter mention"),
),
body: Column(
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
Container(
child: FlutterMentions(
key: key,
suggestionPosition: SuggestionPosition.Top,
maxLines: 5,
minLines: 3,
decoration: InputDecoration(hintText: 'hello'),
mentions: [
Mention(
trigger: '#',
style: TextStyle(
color: Colors.amber,
),
data: data,
matchAll: false,
suggestionBuilder: (data) {
return Container(
padding: EdgeInsets.all(10.0),
child: Row(
children: <Widget>[
SizedBox(
width: 20.0,
),
Column(
children: <Widget>[
Text(data['objectID']),
Text('#${data['username']}'),
],
)
],
),
);
}),
Mention(
trigger: '#',
disableMarkup: true,
style: TextStyle(
color: Colors.blue,
),
data: [
{'id': 'reactjs', 'display': 'reactjs'},
{'id': 'javascript', 'display': 'javascript'},
],
matchAll: true,
)
],
),
),
],
),
),
);
}
}
i build this custom widget of mention which should show a list of users on tapping # and show another list on tapping #, the # trigger is working fine but # trigger is giving following error please help
Nosuchmethoderror : 'toLowerCase'
Dynamic call of null
receiver : null
Arguments : []
how to remove this error and get the list of users from the api call above mentioned , please help api call result is not null i checked it
widget i am using : https://pub.dev/packages/flutter_mentions