JSON Array to JSON Object - json

Question

I'm using a HTTP request that gets a JSON array and pushes this into a JSON object which is read by a list view. I'm having difficulty forcing the JSON array into a JSON object so I'm currently calling each object once via json.decode(response.body)[0]. How can I cast the JSON Array to a JSON Object and have the list view read this entire JSON object?
import 'dart:async';
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
Future<Post> fetchPost() async {
final url = <my_url>;
final response =
await http.get(url);
if (response.statusCode == 200) {
// If the call to the server was successful, parse the JSON.
print(json.decode(response.body));
// TODO: Identify a way to convert JSON Array to JSON Object
return Post.fromJson(json.decode(response.body)[0]);
} else {
// If that call was not successful, throw an error.
throw Exception('Failed to load post');
}
}
class Post {
final String title;
Post({this.title});
factory Post.fromJson(Map<String, dynamic> json) {
return Post(
title: json['title']
);
}
}
void main() => runApp(MyApp());
class MyApp extends StatefulWidget {
MyApp({Key key}) : super(key: key);
#override
_MyAppState createState() => _MyAppState();
}
class _MyAppState extends State<MyApp> {
Future<Post> post;
#override
void initState() {
super.initState();
post = fetchPost();
}
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Fetch Data Example',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: Scaffold(
appBar: AppBar(
title: Text('Fetch Data Example'),
),
body: Center(
child: FutureBuilder<Post>(
future: post,
builder: (context, snapshot) {
if (snapshot.hasData) {
return Text(snapshot.data.title);
} else if (snapshot.hasError) {
return Text("${snapshot.error}");
}
// By default, show a loading spinner.
return CircularProgressIndicator();
},
),
),
),
);
}
}

Answer 1

try this,
Future<List<Post>> fetchPost() async {
final url = <my_url>;
final response =
await http.get(url);
if (response.statusCode == 200) {
// If the call to the server was successful, parse the JSON.
print(json.decode(response.body));
List<dynamic> responseList = json.decode(response.body);
// TODO: Identify a way to convert JSON Array to JSON Object
List<Post> tempList = [];
responseList.forEach((f) {
tempList.add(Post.fromJson(f));
});
return tempList;
} else {
// If that call was not successful, throw an error.
throw Exception('Failed to load post');
}
}
class Post {
final int id;
final String title;
Post({this.id, this.title});
factory Post.fromJson(Map<String, dynamic> json) {
return Post(id: json['id'], title: json['title']);
}
}
class _Frag_CommitteeState extends State<Frag_Committee> {
Future<List<Post>> post;
#override
void initState() {
super.initState();
post = fetchPost();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('Fetch Data Example'),
),
body: Center(
child: FutureBuilder<List<Post>>(
future: post,
builder: (context, snapshot) {
if (snapshot.hasData) {
return ListView.builder(itemCount: snapshot.data.length,
itemBuilder: (BuildContext context, int index) {
return Text(snapshot.data[index].title);
});
} else if (snapshot.hasError) {
return Text("${snapshot.error}");
}
// By default, show a loading spinner.
return CircularProgressIndicator();
},
),
),
);
}
}