这段代码毫无意义。我试图从futurebuilder数据的ALREADY INITIALIZED中抓取一些字符串，但无法做到。它给了我data2尚未初始化的错误。下面是数据和data2，它们几乎是相似的，数据工作正常，但data2不工作。这是为什么？

late List<Album> data;
late List<String> data2;

下面是我的代码：

import 'dart:async';
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;

const List<String> list = <String>['One', 'Two', 'Three', 'Four'];
Future<List<Album>> fetchAlbum() async {
  final response = await http.get(
      Uri.parse('https://my-json-server.typicode.com/fluttirci/testJson/db'));

  print(response);
  Map<String, dynamic> userMap = jsonDecode(response.body);
  if (response.statusCode == 200) {
    return (userMap['employees'] as List)
        .map((e) => Album.fromJson(e))
        .toList();
  } else {
    throw Exception('Failed to load album');
  }
}

class Album {
  final int userId;
  final int id;
  final String title;

  Album(this.userId, this.id, this.title);

  Album.fromJson(Map<String, dynamic> json)
      : userId = json['userId'],
        id = json['id'],
        title = json['title'];

  Map<String, dynamic> toJson() => {
        'userId': userId,
        'id': id,
        'title': title,
      };
}

void main() => runApp(const MyApp());

class MyApp extends StatefulWidget {
  const MyApp({super.key});

  @override
  State<MyApp> createState() => _MyAppState();
}

class _MyAppState extends State<MyApp> {
  late Future<Album> futureAlbum;
  late Future<List<Album>> user;
  late List<Album> data;
  late List<String> data2;
  @override
  void initState() {
    super.initState();
    user = fetchAlbum();
  }

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Fetch Data Example',
      theme: ThemeData(
        brightness: Brightness.dark,
        primarySwatch: Colors.blue,
      ),
      home: Scaffold(
        appBar: AppBar(
          title: const Text('Fetch Data Example'),
        ),
        body: Column(children: <Widget>[
          Expanded(
            child: const DropdownButtonExample(),
          ),
          Expanded(
            child: FutureBuilder<List<Album>>(
              future: user,
              builder: (context, snapshot) {
                if (snapshot.hasData) {
                  data = snapshot.data ?? [];
                  print('${data[4].title}');

                  return ListView.builder(
                    itemBuilder: (context, index) {
                      data2[index] = data[index].title;
                      return Column(children: [
                        Text(data[index].title ?? ""),
                      ]);
                    },
                    itemCount: data.length,
                  );
                } else if (snapshot.hasError) {
                  return Text('${snapshot.error}');
                }
                return Center(
                  child: const CircularProgressIndicator(),
                );
              },
            ),
          )
        ]),
      ),
    );
  }
}

class DropdownButtonApp extends StatelessWidget {
  const DropdownButtonApp({super.key});

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        appBar: AppBar(title: const Text('DropdownButton Sample')),
        body: const Center(
          child: DropdownButtonExample(),
        ),
      ),
    );
  }
}

class DropdownButtonExample extends StatefulWidget {
  const DropdownButtonExample({super.key});

  @override
  State<DropdownButtonExample> createState() => _DropdownButtonExampleState();
}

class _DropdownButtonExampleState extends State<DropdownButtonExample> {
  String dropdownValue = list.first;

  @override
  Widget build(BuildContext context) {
    return DropdownButton<String>(
      value: dropdownValue,
      icon: const Icon(Icons.arrow_downward),
      elevation: 16,
      style: const TextStyle(color: Colors.deepPurple),
      underline: Container(
        height: 2,
        color: Colors.deepPurpleAccent,
      ),
      onChanged: (String? value) {
        // This is called when the user selects an item.
        setState(() {
          dropdownValue = value!;
        });
      },
      items: list.map<DropdownMenuItem<String>>((String value) {
        return DropdownMenuItem<String>(
          value: value,
          child: Text(value),
        );
      }).toList(),
    );
  }
}