Download firestore data into Flutter List - flutter

Question

I am a complete newbie of flutter.
I want to download a simple carparkList from Firestore and put it into a list (or a map??). It appears that the dataset has been successfully downloaded (proved by actually seeing the data from the print(cp)).
But synatx error (a red undeline) apppears at the "[" of both lines:
title: Text(widget.carparkList[index].data().['name']),
subtitle: Text(widget.carparkList[index].data().['district']),
Pls help point out how to correct the syntax error for the following code:
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:flutter/material.dart';
class DownloadDataScreen extends StatefulWidget {
List<DocumentSnapshot> carparkList = []; //List for storing carparks
#override
_DownloadDataScreen createState() => _DownloadDataScreen();
}
class _DownloadDataScreen extends State<DownloadDataScreen> {
#override
void initState() {
readFromFirebase();
super.initState();
}
void readFromFirebase() async {
await FirebaseFirestore.instance
.collection('carpark')
.get()
.then((QuerySnapshot snapshot) {
snapshot.docs.forEach((DocumentSnapshot cp) {
widget.carparkList.add(cp);
// the following 'print' proves that data are successfully downloaded from firestore.
print('printing cp');
print(cp.data().runtimeType);
print(cp.data());
});
});
}
#override
Widget build(BuildContext context) {
return new Scaffold(
appBar: new AppBar(
title: new Text(
'Car Park',
style: TextStyle(fontSize: 20, fontWeight: FontWeight.bold),
),
centerTitle: true,
),
body: Column(
children: [
ListView.builder(
itemCount: widget.carparkList.length,
itemBuilder: (BuildContext context, int index) {
return ListTile(
title: Text(widget.carparkList[index].data().['name']),
subtitle: Text(widget.carparkList[index].data().['district']),
);
},
),
],
),
);
}
}

Answer 1

Change them to this:
title: Text(widget.carparkList[index].get('name')),
subtitle: Text(widget.carparkList[index].get('district')),