listenable_collections

Description:

listenable collections

listenable_collections #
A collection of Dart collections that behave like ValueNotifier if their data changes.
Currently ListNotifier is implemented
planed are:

MapNotifier
SetNotifier

Please check the API documentation for more details
PRs for other collections or test are very welcome
Example for ListNotifier:
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
import 'package:listenable_collections/listenable_collections.dart';

void main() {
runApp(MyApp());
}

class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: MyHomePage(title: 'List Notifier Example'),
);
}
}

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

final String title;

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

class _MyHomePageState extends State<MyHomePage> {
var _list = ListNotifier();

@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Padding(
padding: const EdgeInsets.all(16.0),
child: SingleChildScrollView(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
actionsButtonMenu,
ValueListenableBuilder(
valueListenable: _list,
builder: (context, value, child) => Column(
mainAxisSize: MainAxisSize.max,
crossAxisAlignment: CrossAxisAlignment.start,
children: _list.map<Widget>((value) => Text('List Item: $value')).toList(),
),
)
],
),
),
),
);
}

Row get actionsButtonMenu => Row(
mainAxisAlignment: MainAxisAlignment.center,
children: [
RaisedButton(
onPressed: _addItem,
child: Icon(Icons.add),
),
SizedBox(
width: 16.0,
),
RaisedButton(
onPressed: _removeItem,
child: Icon(Icons.remove),
),
SizedBox(
width: 16.0,
),
RaisedButton(
onPressed: _clearAllItems,
child: Icon(Icons.delete),
),
],
);

void _addItem() {
_list.add('${_list.length}');
}

void _removeItem() {
if (_list.isNotEmpty) _list.removeLast();
}

void _clearAllItems() {
if (_list.isNotEmpty) _list.clear();
}
}
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