在flutter中构建widget之前，如何加载/填充对象？

import 'package:flutter/material.dart';

class MyWidget extends StatelessWidget {
  final String title;

  MyWidget({required this.title});

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(title),
      ),
      body: FutureBuilder(
        future: fetchData(), // 异步加载数据
        builder: (BuildContext context, AsyncSnapshot snapshot) {
          if (snapshot.connectionState == ConnectionState.waiting) {
            return CircularProgressIndicator(); // 加载中的进度条
          } else if (snapshot.hasError) {
            return Text('Error: ${snapshot.error}'); // 加载错误提示
          } else {
            return ListView.builder(
              itemCount: snapshot.data.length,
              itemBuilder: (BuildContext context, int index) {
                return ListTile(
                  title: Text(snapshot.data[index]),
                );
              },
            );
          }
        },
      ),
    );
  }

  Future<List<String>> fetchData() async {
    // 异步加载数据的示例函数
    await Future.delayed(Duration(seconds: 2)); // 模拟网络请求延迟
    return ['Item 1', 'Item 2', 'Item 3']; // 返回一个字符串列表作为示例数据
  }
}

void main() {
  runApp(MaterialApp(
    home: MyWidget(title: 'Data Loading Demo'),
  ));
}