Api 在构造函数中调用setState（）：_WeatherState#823a5（生命周期状态：已创建，无小部件，未安装）错误抖动

天气空气污染指数网页

请帮助我，我的代码有问题，我想从mycity变量更改myURL变量，我有一套city方法：

编辑器错误：在构造函数中调用了setState（）：#WeatherState 823a5（生命周期状态：已创建，无小部件，未装入）

导入'dart:convert'；
进口“包装：颤振/材料.省道”；
导入“package:marwa_app/component/myResponsiveLibrary.dart”；
导入“包装：marwa_app/component/Logo.dart”；
导入“package:marwa_app/component/MyDrawer.dart”；
将“package:http/http.dart”导入为http；
类Weather扩展StatefulWidget{
@凌驾
_WeatherState createState（）；
}
类WeatherState扩展状态{
列出我的城市=[‘亚喀巴’、‘安曼’]；
int i=0；
无效城市值（值）{
设置状态（）{
i=值；
});
}
@凌驾
Future getData（）异步{
字符串myURL=wait'http://api.openweathermap.org/data/2.5/forecast?q=${mycity[i]}&appid=41a6cd80a840ce00a3c77b8ba1a04022&units=metric'；
http.Response-Response=wait-http.get（myURL）；
返回json.decode（response.body）；
}
小部件构建（构建上下文）{
返回脚手架(
背景颜色：MainModel（）.mainColor，
appBar:appBar(
背景颜色：颜色（0xff323266），
领先：IconButton(
图标：图标(
Icons.u处于活动状态，
颜色：MainModel（）.thirdColor，
),
onPressed:（）=>{}），
标题：Logo（），
标题：对，
行动：[
建筑商(
生成器：（上下文）=>IconButton(
图标：图标(
图标菜单，
颜色：MainModel（）.thirdColor，
),
onPressed:（）=>Scaffold.of（context.openEndDrawer（），
工具提示：MaterialLocalizations.of（context）.openAppDrawerTooltip，
),
),
],
),
收尾抽屉(
child:MyDrawer（），
),
正文：widgetMyData（）
);
}
}
Widget widgetMyData（）{
返回FutureBuilder（future:_WeatherState（）.getData（），
生成器：（构建上下文上下文，异步快照snapshop）{
最终宽度屏幕=MediaQuery.of（context）.size.width；
if（snapshop.hasData）{
地图内容=snapshop.data；
返回容器(
颜色：MainModel（）.secondColor，
儿童：中心(
子：ListView(
物理学：NeverscrollableScroll物理学（），
儿童：[
填充（填充：仅限边集（顶部：20）），
容器(
边距：EdgeInsets.symmetric（水平：MainModel（）.setPadding（MainModel（）.largePadding，widthScreen）），
身高：300，
装饰：盒子装饰(
boxShadow：[
箱形阴影(
颜色：颜色。黑色。不透明度（0.15），
扩展半径：5，
半径：5，
偏移量：偏移量（2，2），//更改阴影的位置
),],
borderRadius:borderRadius.all（半径圆形（40）），
梯度：线性梯度(
开始：Alignment.topLeft，
结束：对齐。右下角，
颜色：[
MainModel（）.mainColor，MainModel（）.secondColor
])
),
子：列(
儿童：[
填充（填充：EdgeInsets.only（顶部：MainModel（）.setPadding（MainModel（）.smallPadding，widthScreen）），），
Image.network（'http://openweathermap.org/img/w/${content[“list”][0][“weather”][0][“icon”]}.png'，
颜色：MainModel（）.whiteColor.withOpacity（0.7），
适合：BoxFit.contain，
宽度：120，），
文本（“${content['list'][0]['weather'][0]['description']}”，样式：TextStyle(
fontSize:MainModel（）.setFont（MainModel（）.middleFont，widthScreen），
颜色：MainModel（）.whiteColor.withOpacity（0.7），
),),
Padding（Padding:EdgeInsets.only（顶部：MainModel（）.setPadding（MainModel（）.largePadding*1.5，宽度屏幕）），
文本（${content['list'][0]['main']['temp']}\u00b0C），
样式：TextStyle(
fontSize:MainModel（）.setFont（MainModel（）.largeFont*1.5，宽屏幕），
颜色：MainModel（）.whiteColor，
fontWeight:fontWeight.bold
),),
容器(
对齐：对齐.center，
子项：文本（${content['city']['name']}），样式：TextStyle(
fontSize:MainModel（）.setFont（MainModel（）.middleFont，widthScreen），
颜色：MainModel（）.whiteColor，
),)
),
Padding（Padding:EdgeInsets.only（顶部：MainModel（）.setPadding（MainModel（）.largePadding*1.5，宽度屏幕）），
划船(
mainAxisAlignment:mainAxisAlignment.spaceAround，
儿童：[
文本（${content['list'][0]['main']['temp_max']}\u00b0C），样式：TextStyle(
fontSize:MainModel（）.setFont（MainModel（）.middleFont，widthScreen），
颜色：MainModel（）.whiteColor，
fontWeight:fontWeight.bold
),),
文本（${content['list'][0]['main']['
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:marwa_app/component/myResponsiveLibrary.dart';
import 'package:marwa_app/component/Logo.dart';
import 'package:marwa_app/component/MyDrawer.dart';
import 'package:http/http.dart' as http;


class Weather extends StatefulWidget {
  @override
  _WeatherState createState() => _WeatherState();

}


class _WeatherState extends State<Weather> {
  List <String> mycity = ['aqaba','amman'];
  int i= 0;

  void cityValue(value) {
    setState(() {
      i = value;
    });
  }
  @override

  Future<Map> getData() async{
      String myURL = await 'http://api.openweathermap.org/data/2.5/forecast?q=${mycity[i]}&appid=41a6cd80a840ce00a3c77b8ba1a04022&units=metric';
      http.Response response = await http.get(myURL);
      return json.decode(response.body);
  }


  Widget build(BuildContext context) {
    return Scaffold(
        backgroundColor: MainModel().mainColor,
        appBar: AppBar(
          backgroundColor: Color(0xff323266),
          leading: IconButton(
              icon: Icon(
                Icons.notifications_active,
                color: MainModel().thirdColor,
              ),
              onPressed: () => {}),
          title: Logo(),
          centerTitle: true,
          actions: [
            Builder(
              builder: (context) => IconButton(
                icon: Icon(
                  Icons.menu,
                  color: MainModel().thirdColor,
                ),
                onPressed: () => Scaffold.of(context).openEndDrawer(),
                tooltip: MaterialLocalizations.of(context).openAppDrawerTooltip,
              ),
            ),
          ],
        ),
        endDrawer: Drawer(
          child: MyDrawer(),
        ),
        body: widgetMyData()
    );
  }
}
Widget widgetMyData() {

  return FutureBuilder(future: _WeatherState().getData(),
      builder: (BuildContext context, AsyncSnapshot<Map> snapshop){
        final widthScreen = MediaQuery.of(context).size.width;
        if(snapshop.hasData){
          Map content = snapshop.data;


          return Container(
            color: MainModel().secondColor,
            child: Center(
              child: ListView(
                  physics: NeverScrollableScrollPhysics(),
                  children: [
                Padding(padding: EdgeInsets.only(top: 20)),

                Container(
                  margin: EdgeInsets.symmetric(horizontal: MainModel().setPadding(MainModel().largePadding, widthScreen)),
                  height: 300,
                  decoration: BoxDecoration(
                      boxShadow: [
                        BoxShadow(
                          color: Colors.black.withOpacity(0.15),
                          spreadRadius: 5,
                          blurRadius: 5,
                          offset: Offset(2, 2), // changes position of shadow
                        ),],
                      borderRadius: BorderRadius.all(Radius.circular(40)),
                      gradient: LinearGradient(
                          begin: Alignment.topLeft,
                          end: Alignment.bottomRight,
                          colors: [
                            MainModel().mainColor, MainModel().secondColor
                          ])
                  ),
                  child: Column(
                    children: [
                      Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().smallPadding, widthScreen)),),
                      Image.network('http://openweathermap.org/img/w/${content["list"][0]["weather"][0]["icon"]}.png',
                        color: MainModel().whiteColor.withOpacity(0.7),
                        fit: BoxFit.contain,
                        width: 120,),
                      Text('${content['list'][0]['weather'][0]['description']}',style: TextStyle(
                        fontSize: MainModel().setFont(MainModel().middleFont, widthScreen),
                        color: MainModel().whiteColor.withOpacity(0.7),
                      ),),
                      Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding * 1.5, widthScreen)),),
                      Text("${content['list'][0]['main']['temp']}\u00b0C",
                        style: TextStyle(
                            fontSize: MainModel().setFont(MainModel().largeFont * 1.5, widthScreen),
                            color: MainModel().whiteColor,
                            fontWeight: FontWeight.bold
                        ),),
                      Container(
                          alignment: Alignment.center,
                          child: Text("${content['city']['name']}",style: TextStyle(
                            fontSize: MainModel().setFont(MainModel().middleFont, widthScreen),
                            color: MainModel().whiteColor,
                          ),)
                      ),
                      Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding * 1.5, widthScreen)),),
                      Row(
                        mainAxisAlignment: MainAxisAlignment.spaceAround,
                        children: [
                          Text("${content['list'][0]['main']['temp_max']}\u00b0C",style: TextStyle(
                              fontSize: MainModel().setFont(MainModel().middleFont, widthScreen),
                              color: MainModel().whiteColor,
                              fontWeight: FontWeight.bold
                          ),),
                          Text("${content['list'][0]['main']['temp_min']}\u00b0C",style: TextStyle(
                              fontSize: MainModel().setFont(MainModel().middleFont, widthScreen),
                              color: MainModel().whiteColor,
                              fontWeight: FontWeight.bold
                          ),),
                        ],
                      ),
                    ],
                  ),
                ),
                Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding * 2, widthScreen))),
                SingleChildScrollView(
                    scrollDirection: Axis.horizontal,
                    child: Row(
                      children: [
                        Padding(padding: EdgeInsets.only(left: MainModel().setPadding(MainModel().middlePadding, widthScreen))),
                        Container(
                            height: MainModel().setSize(MainModel().largeSize, widthScreen),
                            width: MainModel().setSize(MainModel().largeSize, widthScreen),
                            decoration: BoxDecoration(
                              color: Color(0xffFFB20F),
                              borderRadius: BorderRadius.all(Radius.circular(40.0)),
                            ),
                            child: Column(
                              crossAxisAlignment: CrossAxisAlignment.center,
                              children: [
                                Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding, widthScreen))),

                              ],
                            )
                        ),
                        Padding(padding: EdgeInsets.only(left: MainModel().setPadding(MainModel().middlePadding, widthScreen))),

                        Container(
                            height: MainModel().setSize(MainModel().largeSize, widthScreen),
                            width: MainModel().setSize(MainModel().largeSize, widthScreen),
                            decoration: BoxDecoration(
                              color: Color(0xff0DA6A6),
                              borderRadius: BorderRadius.all(Radius.circular(40.0)),
                            ),
                            child: Column(
                              crossAxisAlignment: CrossAxisAlignment.center,
                              children: [
                                Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding, widthScreen))),
                              ],
                            )
                        ),
                        Padding(padding: EdgeInsets.only(left: MainModel().setPadding(MainModel().middlePadding, widthScreen))),

                        Container(
                            height: MainModel().setSize(MainModel().largeSize, widthScreen),
                            width: MainModel().setSize(MainModel().largeSize, widthScreen),
                            decoration: BoxDecoration(
                              color: Color(0xff6D5DF1),
                              borderRadius: BorderRadius.all(Radius.circular(40.0)),
                            ),
                            child: Column(
                              crossAxisAlignment: CrossAxisAlignment.center,
                              children: [
                                Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding, widthScreen))),
                              ],
                            )
                        ),
                        Padding(padding: EdgeInsets.only(left: MainModel().setPadding(MainModel().middlePadding, widthScreen))),
                        FlatButton(onPressed: () {
                          _WeatherState().cityValue(1);
                        },
                            child: Container(
                                height: MainModel().setSize(MainModel().largeSize, widthScreen),
                                width: MainModel().setSize(MainModel().largeSize, widthScreen),
                                decoration: BoxDecoration(
                                  color: Color(0xffFF0F97),
                                  borderRadius: BorderRadius.all(Radius.circular(40.0)),
                                ),
                                child: Column(
                                  crossAxisAlignment: CrossAxisAlignment.center,
                                  children: [
                                    Text('click'),
                                    Padding(padding: EdgeInsets.only(top: MainModel().setPadding(MainModel().largePadding, widthScreen))),
                                  ],
                                )
                            ),
                        ),
                        Padding(padding: EdgeInsets.only(left: MainModel().setPadding(MainModel().middlePadding, widthScreen))),

                      ],
                    ))
              ]),
            ),
          );
        }else{
          return Container(
            child: Text('sorry you data is not found'),
          );
        }
      }
  );
}

  Future<Map> _future;
  ...
  @override
  initState() {
    _future = getData();
    super.initState();
  }
  ...
  body: widgetMyData(_future, cityValue));
  
  ...
  Widget widgetMyData(Future<Map> _future, Function callback) {
     return FutureBuilder(
       future: _future,
       ...
       FlatButton(
            onPressed: () {
              callback(1);
            },
            child: Text('click'))

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

class Weather extends StatefulWidget {
  @override
  _WeatherState createState() => _WeatherState();
}

class _WeatherState extends State<Weather> {
  List<String> mycity = ['aqaba', 'amman'];
  int i = 0;
  Future<Map> _future;

  void cityValue(value) {
    setState(() {
      i = value;
      _future = getData();
    });
  }

  @override
  initState() {
    _future = getData();
    super.initState();
  }

  Future<Map> getData() async {
    String myURL =
        await 'https://api.openweathermap.org/data/2.5/forecast?q=${mycity[i]}&appid=41a6cd80a840ce00a3c77b8ba1a04022&units=metric';
    http.Response response = await http.get(myURL);
    return json.decode(response.body);
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
        //backgroundColor: MainModel().mainColor,
        appBar: AppBar(
          backgroundColor: Color(0xff323266),
          leading: IconButton(
              icon: Icon(
                Icons.notifications_active,
                //color: MainModel().thirdColor,
              ),
              onPressed: () => {}),
          title: Text("Logo()"),
          centerTitle: true,
          actions: [
            Builder(
              builder: (context) => IconButton(
                icon: Icon(
                  Icons.menu,
                  //color: MainModel().thirdColor,
                ),
                onPressed: () => Scaffold.of(context).openEndDrawer(),
                tooltip: MaterialLocalizations.of(context).openAppDrawerTooltip,
              ),
            ),
          ],
        ),
        body: widgetMyData(_future, cityValue));
  }
}

Widget widgetMyData(Future<Map> _future, Function callback) {
  return FutureBuilder(
      future: _future,
      builder: (BuildContext context, AsyncSnapshot<Map> snapshop) {
        final widthScreen = MediaQuery.of(context).size.width;
        if (snapshop.hasData) {
          Map content = snapshop.data;

          return Container(
            child: Center(
              child:
                  ListView(physics: NeverScrollableScrollPhysics(), children: [
                Padding(padding: EdgeInsets.only(top: 20)),
                Container(
                  height: 300,
                  decoration: BoxDecoration(
                      boxShadow: [
                        BoxShadow(
                          color: Colors.black.withOpacity(0.15),
                          spreadRadius: 5,
                          blurRadius: 5,
                          offset: Offset(2, 2), // changes position of shadow
                        ),
                      ],
                      borderRadius: BorderRadius.all(Radius.circular(40)),
                      gradient: LinearGradient(
                          begin: Alignment.topLeft,
                          end: Alignment.bottomRight,
                          colors: [Colors.blue, Colors.red])),
                  child: Column(
                    children: [
                      Image.network(
                        'https://openweathermap.org/img/w/${content["list"][0]["weather"][0]["icon"]}.png',
                        //color: MainModel().whiteColor.withOpacity(0.7),
                        fit: BoxFit.contain,
                        width: 120,
                      ),
                      Text(
                        '${content['list'][0]['weather'][0]['description']}',
                      ),
                      Text(
                        "${content['list'][0]['main']['temp']}\u00b0C",
                      ),
                      Container(
                          alignment: Alignment.center,
                          child: Text(
                            "${content['city']['name']}",
                          )),
                      Row(
                        mainAxisAlignment: MainAxisAlignment.spaceAround,
                        children: [
                          Text(
                            "${content['list'][0]['main']['temp_max']}\u00b0C",
                          ),
                          Text(
                            "${content['list'][0]['main']['temp_min']}\u00b0C",
                          ),
                        ],
                      ),
                    ],
                  ),
                ),
                SingleChildScrollView(
                    scrollDirection: Axis.horizontal,
                    child: Row(
                      children: [
                        FlatButton(
                            onPressed: () {
                              callback(1);
                            },
                            child: Text('click')),
                      ],
                    ))
              ]),
            ),
          );
        } else {
          return Container(
            child: Text('sorry you data is not found'),
          );
        }
      });
}

void main() {
  runApp(MyApp());
}

class MyApp extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'Flutter Demo',
      theme: ThemeData(
        primarySwatch: Colors.blue,
        visualDensity: VisualDensity.adaptivePlatformDensity,
      ),
      home: Weather(),
    );
  }
}

class MyHomePage extends StatefulWidget {
  MyHomePage({Key key, this.title}) : super(key: key);

  final String title;

  @override
  _MyHomePageState createState() => _MyHomePageState();
}

class _MyHomePageState extends State<MyHomePage> {
  int _counter = 0;

  void _incrementCounter() {
    setState(() {
      _counter++;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(
              'You have pushed the button this many times:',
            ),
            Text(
              '$_counter',
              style: Theme.of(context).textTheme.headline4,
            ),
          ],
        ),
      ),
      floatingActionButton: FloatingActionButton(
        onPressed: _incrementCounter,
        tooltip: 'Increment',
        child: Icon(Icons.add),
      ),
    );
  }
}