Flutter http 请求获取 null

我对Flutter 翼和dart 还是个新手.在学习关于http请求的GET时，我遇到了一些错误.这些是我的代码

import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as ziraHttp;
class getHttp extends StatefulWidget {
  const getHttp({super.key});
  @override
  State<getHttp> createState() => _getHttpState();
}
class _getHttpState extends State<getHttp> {
  late String id;
  late String email;
  late String name;
  @override
  void initState() {
    id = '';
    email = '';
    name = '';
    super.initState();
  }
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text("Get Tutorial"),
        centerTitle: true,
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: [
            Text(
              "ID:$id ",
              style: TextStyle(fontSize: 20),
            ),
            Text(
              "email:$email ",
              style: TextStyle(fontSize: 20),
            ),
            Text(
              "Name:$name ",
              style: TextStyle(fontSize: 20),
            ),
            SizedBox(
              height: 12,
            ),
            ElevatedButton(
connection )
                onPressed: () async {
                  var serverResponse = await ziraHttp
                      .get(Uri.parse('https://reqres.in/api/users/2'));
                  if (serverResponse.statusCode == 200) {
                    Map<String, dynamic> dataResp =
                        json.decode(serverResponse.body);
                    setState(() {
                      id = dataResp["id"].toString();
                      email = dataResp["email"].toString();
                      name =
                          "${dataResp["first_name"]} ${dataResp["last_name"]}";
                    });
                  } else {
                    print("ERROR CODE: ${serverResponse.statusCode}");
                  }
                },
                child: Text("Get Data"))
          ],
        ),
      ),
    );
  }
}

当我单击该按钮时，显示的不是数据，而是空 enter image description here个

我可能犯了一些错误，因为我是这个语言的新手，这是我第一次在这里发帖.提前谢谢！