Flutter / JSON: instance member cannot be accessed using static access

Question

Here is a complete code snippet that should demonstrate the issue that I am bumping into.

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

void main() async {
  WidgetsFlutterBinding.ensureInitialized();
  SystemChrome.setPreferredOrientations([
    DeviceOrientation.landscapeLeft,
    DeviceOrientation.landscapeRight,
  ]);
  SystemChrome.setEnabledSystemUIOverlays([]);
  runApp(
    MaterialApp(
      home: MyHomePage(),
    ),
  );
}

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

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

Future<latestVersion> fetchAlbum() async {
  final response = await http.get('https://api.jsonbin.io/b/5fd25941bef8b7699e57dce9');
  if (response.statusCode == 200) {
    print('yay');
    return latestVersion.fromJson(jsonDecode(response.body));
  } else {
    print('nay');
    throw Exception('Failed to load version');
  }
}

class latestVersion {
  final String title;
  final String version;

  latestVersion({this.version, this.title});

  factory latestVersion.fromJson(Map<String, dynamic> json) {
    return latestVersion(version: json['version'], title: json['title'],
    );
  }
}

class _MyHomePageState extends State<MyHomePage> {
  static Future<latestVersion> futureAlbum;

  @override
  void initState() {
    super.initState();
    futureAlbum = fetchAlbum();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.yellow,
      body: Center(
        child: Column(
          mainAxisAlignment: MainAxisAlignment.center,
          children: <Widget>[
            Text(''),
            Text('CURRENT'),
            Text('---------'),
            Text('0.37'),
            Text(''),
            Text('LATEST'),
            Text('--------'),
            Text(latestVersion.version),
            Text(''),
            Text(''),
          ],
        ),
      ),
    );
  }
}

When trying to run this code, I get an error at line 76.

"instance member 'version' cannot be accessed using static access"

How exactly can I access this json-decoded variable? Thank you in advance. I'm new to working with asynchronous functions and Future and would appreciate any help that can be given.

Solution

The error means version is not a Static variable. So to access it like this LatestVersion.version either make version a static variable or

Replace

Text(LatestVersion.version),

with

Text(LatestVersion().version),

If everything else is correct in your code the above should work.

Comments

[beansbeans]

Thank you. This is absolutely correct. Now I'm bumping into an issue that my value is null. but that's a different problem that I'll need to handle on my own. Thank you so much for your help.