callvaluenotifier 0.0.1 callvaluenotifier: ^0.0.1 copied to clipboard
ValueNotifier that updates from a given callable.
import 'package:flutter/material.dart';
import 'package:callvaluenotifier/callvaluenotifier.dart';
void main() {
runApp(MyApp());
}
Future<String> getMyValue() {
return Future.delayed(
Duration(seconds: 2), () => 'I am the future result value');
}
final myValue = CallValueNotifier<String>('I am the default value', getMyValue);
class MyApp extends StatelessWidget {
@override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.pink,
),
home: MyHomePage(),
);
}
}
class MyHomePage extends StatelessWidget {
int _counter = 0;
void reset() {
myValue.reset();
myValue.fetch();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('CallValueNotifier Demo'),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'This text will update',
),
ValueListenableBuilder<String>(
valueListenable: myValue,
builder: (BuildContext context, String value, Widget child) {
return Text(
'$value',
style: Theme.of(context).textTheme.headline4,
);
}),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: reset,
tooltip: 'Reset',
child: Icon(Icons.refresh),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
}