底部溢出 99397 像素的 RenderFlex

Question

import 'package:flutter/material.dart';
import 'package:http_request/carditem.dart';
import 'package:http_request/user_data.dart';

// here we chose to have statefull widget because the state needs to be updated and we need to update some variables according to some conditions.
class UserScreen extends StatefulWidget {
  const UserScreen({Key key}) : super(key: key);

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

class _UserScreenState extends State<UserScreen> {
  // here we created a variable to keep our information in it . this information comes from our user data class where we get the user data from http requests.
  Map<String, dynamic> userinfo = {};

  // this method is called as soon as the main widget is created . we call our http method here to have the live data as soon as we open the app .be aware that we cant use async and await here . we just call the method.
  @override
  void initState() {
    super.initState();
    getData();
  }

  // here we get hte live data from our userdata class .
  Future getData() async {
    //we create a userData object to get access to the getuserdata method.
    UserData userData = UserData();
    //we handle any error here
    try {
      // here we create a variable to the exact same type we are expecting .
      //then we wait for the result of calling our userdata information.
      Map<String, dynamic> data = await userData.getUserData();
      // we call setState because we need to update a certain value here.
      setState(() {
        //we assign the the value of data to our variable called userinfo .try the reaosn we see no error behind them is that they are the same type.
        userinfo = data;
      });
      // we catch errors here .
    } catch (e) {
      print(e);
    }
  }

  // our nice build method ...this method is from our stateful class.
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Work Harder'),
        centerTitle: true,
      ),
      body: ListView.builder(
        itemBuilder: (context, index) => CardItem(
          firstName: userinfo['firstName'],
          avatarLink: userinfo['avatarLink'],
          id: userinfo['id'],
          lastName: userinfo['lastName'],
          email: userinfo['email'],
        ),
      ),
    );
  }
}

as you can see here is my user_screen dart file the problem is when i hot reload the app  is see the renderflex error, while everything seems fine. im  a begginner in flutter and i would really appreciate your help.

i have tried singlechild scrollview, list view, expanded widget, but it doesn't work. please help me hotrestart may app without these long errors

import 'package:flutter/material.dart';

// we chose stateless because we don't need to change the state of our app.
class CardItem extends StatelessWidget {
  const CardItem({
    Key key,
    this.firstName,
    this.email,
    this.avatarLink,
    this.id,
    this.lastName,
  }) : super(key: key);
  final String firstName;
  final String email;
  final String avatarLink;
  final String id;
  final String lastName;

  @override
  Widget build(BuildContext context) {
    return Card(
      color: Colors.lightBlueAccent[200],
      elevation: 3,
      shadowColor: Colors.blue[100],
      child: Column(
        children: [
          Stack(
            children: [
              ListTile(
                leading: Icon(Icons.check_box),
                trailing: CircleAvatar(
                  child: Image.network(avatarLink),
                ),
                title: Text(firstName),
                subtitle: Text(lastName),
              ),
              Positioned(
                left: 48,
                top: 15,
                child: Text(
                  id,
                  style: TextStyle(
                    color: Colors.white70,
                    fontSize: 20,
                    fontWeight: FontWeight.bold,
                  ),
                ),
              ),
              Positioned(
                left: 120,
                top: 30,
                child: Text(
                  'Email :  $email',
                  style: TextStyle(
                    color: Colors.blue[900].withOpacity(0.6),
                  ),
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }
}

 

here is my card widget, if it helps.

import 'dart:convert';

import 'package:http/http.dart' as http;

// this is the file for our main http requests.
class UserData {
  UserData({
    this.firstName,
    this.lastName,
    this.email,
    this.id,
    this.avatarLink,
  });
  final String firstName;
  final String lastName;
  final String email;
  final String id;
  final String avatarLink;

  //this method is response for getting the live data we want also its responsible for decoding it with 'dart convert' library and returning the result as an output.
  Future getUserData() async {
    //the url we are working with
    final String stringUrl = 'https://reqres.in/api/users?page=2';
    //sending the request to web and storing the result to a variable. we also have to wait for the results . (asynchronous operation).
    http.Response response = await http.get(
      Uri.parse(stringUrl),
    );
    //we create a variable to the exact type of our output . we want to add our items to this map to use it in the main screen.
    Map<String, dynamic> userdetails = {};
    //here we want to check if our request was successful if so, we continue our operation and if not we throw an error .
    if (response.statusCode == 200) {
      // here we are decoding the data that we got from our request above to a variable of type map.
      Map<String, dynamic> decodedData = jsonDecode(response.body);
      //here we try to iterate through a map .. but im not sure if its correct or not .
      for (var user in decodedData.values) {
        Map<String, dynamic> myusersInfo = {
          'firstName': decodedData['data'][0]['first_name'],
          'lastName': decodedData['data'][0]['last_name'],
          'email': decodedData['data'][0]['email'],
          'id': decodedData['data'][0]['id'].toString(),
          'avatarLink': decodedData['data'][0]['avatar'],
        };
        // here we are trying to add the items to the map specified.
        userdetails.addEntries(myusersInfo.entries);

        return userdetails;
      }
    } else {
      print(response.statusCode);
      throw 'Problem with the get request';
    }
  }
}

the whole goal of this app was to practice some http request. the last file I have in this app. I just added this maybe it helps you. thanks in advance.

Answer 1

A Column likes to expand until infinity. This can be solved by putting an intrinsicHeight around the Column as followed:

This class is useful, for example, when unlimited height is available and you would like a child that would otherwise attempt to expand infinitely to instead size itself to a more reasonable height.

IntrinsicHeight(
   child: Column(
      children: [

      ],
   )
);

https://api.flutter.dev/flutter/widgets/IntrinsicHeight-class.html

Answer 2

try column inside SingleChildScrollView