setState 在颤动的 Android Studio 中无法识别

Question

我在互联网上看到了答案，但在所有这些答案中，OP 使用的是 StatelessWidget 而不是 StatefulWidget。我使用了 StatefulWidget，但仍然无法识别 setState()

请参考代码第43行。

嗨！我正在尝试学习 flutter 并正在制作一个天气预报应用程序作为一个项目为了实现这一点，我正在关注 youtube 上的教程，youtuber 在使用 visual studio 代码时没有出现任何错误，另一方面，我正在使用 Android studio

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

void main() => runApp(
 MaterialApp(
 title: "Weather App",
 home: Home(),
 )//MaterialApp
 );

class Home extends StatefulWidget {


 @override
 State<StatefulWidget>createState()
 {
  return _HomeState();
 }

 @override
 Widget build(BuildContext context) {
  // TODO: implement build

   throw UnimplementedError();
   }
  }

class _HomeState extends State<Home>{

  var temp;
  var description;
  var currently;
  var humidity;
  var windSpeed;

  Future getWeather() async {
   http.Response response = await http.get(
        "https://api.openweathermap.org/data/2.5/weather?q=Delhi&APPID=4570e05ab53aad5b3893831a809ee608");
var results = jsonDecode(response.body);

  setState((){                                      //<- THIS IS NOT RECOGNIZED
    this.temp = results['main']['temp'];
    this.description = results['weather'][0]['description'];
    this.currently = results['weather'][0]['main'];
    this.humidity = results['main']['humidity'];
    this.windSpeed = results['main']['speed'];
  })
  }
  @override
  Widget build (BuildContext context)
  {
    return Scaffold(
    body: Column(
     children: <Widget>[
       Container(
        height: MediaQuery.of(context).size.height / 3,
        width: MediaQuery.of(context).size.width,
        color: Colors.red,
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center ,
          crossAxisAlignment: CrossAxisAlignment.center,
          children: <Widget>[
            Padding(
              padding: EdgeInsets.only(bottom: 10.0),
              child: Text(
                "Currently in Boston",
                style: TextStyle
                  (
                  color:  Colors.white,
                  fontSize: 14.0,
                  fontWeight: FontWeight.w600
                  ),
              ),

            ),
            Text(
              "52\u00B0",
              style:TextStyle(
                color: Colors.white,
                fontSize:40.0,
                fontWeight: FontWeight.w600
              ),
            ),
            Padding(
                padding: EdgeInsets.only(bottom: 10.0),
                child: Text(
                    "Rain",
                    style: TextStyle
                      (
                        color:  Colors.white,
                        fontSize: 14.0,
                        fontWeight: FontWeight.w600
                    ),
                ),

            ),
          ],
        ),
      ),
      Expanded(child: Padding(
        padding: EdgeInsets.all(20.0),
        child:ListView(
          children: <Widget>[
            ListTile(
              leading: FaIcon(FontAwesomeIcons.temperatureHalf),
              title: Text("Temprature"),
              trailing: Text("52\u00B0"),
            ),
            ListTile(
              leading: FaIcon(FontAwesomeIcons.cloud),
              title: Text("Weather"),
              trailing: Text("Weather"),
            ),
            ListTile(
              leading: FaIcon(FontAwesomeIcons.sun),
              title: Text("Humidity"),
              trailing: Text("12"),
            ),
            ListTile(
              leading: FaIcon(FontAwesomeIcons.wind),
              title: Text("Wind Speed"),
              trailing: Text("12"),
            ),
          ],
        )
      ))
    ],
  ),
);
  }

 }

Answer 1

我认为您需要调用函数 getWeather，例如在初始化状态方法中。

@override
  initState() {
    getWeather();
  }

Answer 2

已修复！少了一个分号。

Answer 3

你的 setState((){...})[ 末尾缺少一个 ; =11=]

我认为你应该使用 Uri.parse():

http.Response response = await http.get(
    Uri.parse("https://api.openweathermap.org/data/2.5/weather?q=Delhi&APPID=4570e05ab53aad5b3893831a809ee608"));

setState 在颤动的 Android Studio 中无法识别

setState not recognized in flutter Androidstudio

dart

android-studio

visual-studio-code

flutter