如何在字串串列中回傳未來串列？-有解無憂

我嘗試抓取網站以獲取一些資料（標題），然后將其存盤在字串串列中，以便稍后在我的文本小部件中使用，但問題是我的串列中沒有資料，為什么會這樣？當我在我的 dd 串列中使用 await 時，向我顯示錯誤，我需要讓我的 func 未來我嘗試在我的代碼中解釋更多請看這是我的代碼

// ignore: prefer_const_constructors

import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:html/parser.dart';
import 'package:http/http.dart' as http;
import 'package:weatherapp/Test/datapars.dart';

class DataP extends StatelessWidget {
  late List<String> dd = [];

  Future<List<String>> arageek() async {
    List<String> title = [];
    var uri = Uri.parse('exmple.com');
    var respons = await http.get(uri);
    var doc = parse(respons.body);
    final className =
        doc.getElementsByClassName('WidePostCard_postTitle__SRltQ');

    for (final data in className) {
      title.add(data.text.toString());
      print(data.text); // it show me all the title in my console
    }
    return title; // when i print this its show me list of my all title i get
  }

  @override
  Widget build(BuildContext context) {
    dd = await arageek(); // here result is emty and tell cant use await
    print(dd);// show emty []
    return Container(
      alignment: Alignment.center,
      child: Text(
        'ddddddddddddd',
        style: TextStyle(fontSize: 20),
      ),
    );
  }
}

uj5u.com熱心網友回復：

usingFutureBuilder可以解決您的問題，此入門代碼可能會幫助您：

class DataP extends StatelessWidget {
  late List<String> dd = [];

  Future<List<String>> arageek() async {
    List<String> title = [];
    var uri = Uri.parse('exmple.com');
    var respons = await http.get(uri);
    var doc = parse(respons.body);
    final className =
        doc.getElementsByClassName('WidePostCard_postTitle__SRltQ');

    for (final data in className) {
      title.add(data.text.toString());
      print(data.text); // it show me all the title in my console
    }
    return title; // when i print this its show me list of my all title i get
  }

  @override
  Widget build(BuildContext context) {
    return FutureBuilder(
        // Initialize FlutterFire:
        future: arageek(),
        builder: (context, yourListOfStringResult) {
          // Check for errors
          if (yourListOfStringResult.hasError) {
            return Text("something is wrong!");
            
          } else   if (yourListOfStringResult.connectionState == ConnectionState.done) {
            List<String> data = yourListOfStringResult.data as List<String>; //
            return Container(
              alignment: Alignment.center,
              child: Text(
                'ddddddddddddd',
                style: TextStyle(fontSize: 20),
              ),
            );
          }else return CircularProgressIndicator();
        });
  }
}

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