bloc todo

import 'package:flutter/material.dart';

import "dart:async";

import "dart:convert";

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

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

class MyApp extends StatelessWidget {

@override

Widget build(BuildContext context) {

return TodoProvider(

todoBloc: TodoBloc(API()),

child: MaterialApp(

debugShowCheckedModeBanner: false,

title: "flutter demo",

theme: ThemeData(primarySwatch: Colors.blue),

home: TodoPage()));

}

}

class TodoBloc {

final API api;

StreamController<List<Todo>> ctrl = StreamController();

Stream<List<Todo>> get results => ctrl.stream;

TodoBloc(this.api);

void dispose() {

ctrl.close();

}

void getTodo() {

api.getTodo().then((todos) {

ctrl.add(todos);

});

}

}

class TodoPage extends StatefulWidget {

@override

TodoPageState createState() => TodoPageState();

}

class TodoPageState extends State<TodoPage> {

@override

Widget build(BuildContext context) {

final todoBloc = TodoProvider.of(context);

return Scaffold(

appBar: AppBar(

title: Text("title"),

),

body: Center(

child: Column(

children: <Widget>[

Text("Stream Builder with Bloc"),

RaisedButton(

color: Colors.lightBlueAccent[200],

child: Text(

"Load Data",

style: TextStyle(color: Colors.white),

),

onPressed: todoBloc.getTodo,

),

Flexible(

//https://docs.flutter.io/flutter/widgets/StreamBuilder-class.html

child: StreamBuilder(

stream: todoBloc.results,

/*

build method

@override

Widget build (

BuildContext context,

AsyncSnapshot<T> currentSummary

)

override

Returns a Widget based on the currentSummary.

*/

builder: (context, snapshot) {

if (!snapshot.hasData) {

return Text("No data");

} else {

return ListView.builder(

itemCount: snapshot.data.length,

itemBuilder: (context, index) =>

_buildListTile(snapshot, index),

);

}

}),

)

],

),

));

}

//리스트뷰에 들어갈 타일을 만든다.

Widget _buildListTile(AsyncSnapshot snapshot, int index) {

var id = snapshot.data[index].id;

var title = snapshot.data[index].title;

bool completed = snapshot.data[index].completed;

print("111 snapshot.data[index] : ${snapshot.data[index]}");

print("111 complete : $completed");

//한개의 고정높이의 row single fixed-heigh row

//텍스트와 그 텍스트의 leading 혹은 trailing에 아이콘을 가짐

// title : The primary content of the list tile

// subtitle : Additional content displayed below title

// leading : A widget to display before the title;\

// tailing : A widget to display after the title

// 한개에서 3개의 텍스트 라인을 가짐.

//https://medium.com/@studymongolian/a-complete-guide-to-flutters-listtile-597a20a3d449

//https://docs.flutter.io/flutter/material/ListTile-class.html

return ListTile(

leading: Text('$id'),

title: Text('$title'),

subtitle: Text("completed",

style: TextStyle(color: completed ? Colors.lightBlue : Colors.red)),

);

}

}

//bloc는 항상 provider를 통해서 사용합니다.

class TodoProvider extends InheritedWidget {

final TodoBloc todoBloc;

static TodoBloc of(BuildContext context) {

return (context.inheritFromWidgetOfExactType(TodoProvider) as TodoProvider)

.todoBloc;

}

@override

bool updateShouldNotify(InheritedWidget oldWidget) {

return true;

}

TodoProvider({Key key, TodoBloc todoBloc, Widget child})

:

// Assign value to b if b is null; otherwise, b stays the same

//b ??= value;

this.todoBloc = todoBloc ?? TodoBloc(API()),

super(child: child, key: key);

}

class API {

final http.Client _client = http.Client();

static const String _url = "https://jsonplaceholder.typicode.com/todos";

Future<List<Todo>> getTodo() async {

List<Todo> list = [];

await _client

.get(Uri.parse(_url))

.then((res) => res.body)

.then(json.decode)

.then(

(todos) => todos.forEach((todo) => list.add(Todo.fromJson(todo))));

return list;

}

}

class Todo {

int userId;

int id;

String title;

bool completed;

Todo(this.userId, this.id, this.title, this.completed);

Todo.fromJson(Map json)

: userId = json["userId"],

id = json["id"],

title = json["title"],

completed = json["completed"];

@override

String toString() {

return 'completed : $completed';

}

}

https://software-creator.tistory.com/13