HTTP Flutter Template

HTTP_Flutter_main.dart

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

import 'Todo.dart';

Future<List<Todo>> fetchTodos(http.Client client, BuildContext context) async {
  final response =
      await client.get('https://jsonplaceholder.typicode.com/todos');

  if (response.statusCode == 200) {
    // If server returns an OK response, parse the JSON.
    return compute(parseTodos, response.body);
  } else {
    // If that response was not OK, throw an error.
    throw Exception('Failed to load post');
  }
}

List<Todo> parseTodos(String responseBody) {
  final parsed = json.decode(responseBody).cast<Map<String, dynamic>>();

  return parsed.map<Todo>((json) => Todo.fromJson(json)).toList();
}

void main() => runApp(MyApp());

class MyApp extends StatelessWidget {
  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      title: 'http get',
      theme: ThemeData(
        primarySwatch: Colors.blue,
      ),
      home: MyHomePage(title: 'Flutter Demo Home Page'),
    );
  }
}

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

  final String title;

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

class _MyHomePageState extends State<MyHomePage> {
  List<Todo> todos;
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text(widget.title),
      ),
      body: ListView.builder(
        itemCount: todos == null ? 0 : todos.length,
        itemBuilder: (context, index) {
          return ListTile(
            title: new Text(todos[index].title),
            leading: new Text('${todos[index].userId}'),
            subtitle: new Text('${todos[index].id}'),
            trailing: new Text('${todos[index].completed}'),
          );
        },
      ),
      floatingActionButton: FloatingActionButton(
        child: Icon(Icons.list),
        onPressed: () async {
          todos = await fetchTodos(http.Client(), context);
          setState(() {});
        },
      ),
    );
  }
}

class TodosList extends StatelessWidget {
  final List<Todo> todos;

  TodosList({Key key, this.todos}) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
      itemCount: todos.length,
      itemBuilder: (context, index) {
        return ListTile(
          title: new Text(todos[index].title),
          leading: new Text('${todos[index].userId}'),
          subtitle: new Text('${todos[index].id}'),
          trailing: new Text('${todos[index].completed}'),
        );
      },
    );
  }
}

HTTP_Flutter_Todo.dart

class Todo {
  int userId;
  int id;
  String title;
  bool completed;

  // Sugar syntax
  Todo({this.userId, this.id, this.title, this.completed});

  factory Todo.fromJson(Map<String, dynamic> json) {
    return Todo(
      userId: json['userId'],
      id: json['id'],
      title: json['title'],
      completed: json['completed'],
    );
  }
}