92 lines
2.0 KiB
Dart
92 lines
2.0 KiB
Dart
import 'package:flutter/material.dart';
|
|
import 'package:provider/provider.dart';
|
|
|
|
class ConsumerPage extends StatelessWidget {
|
|
const ConsumerPage({super.key});
|
|
|
|
@override
|
|
Widget build(BuildContext context) {
|
|
return ChangeNotifierProvider(
|
|
create: (_) => Counter(),
|
|
child: Scaffold(
|
|
appBar: AppBar(
|
|
title: const Text('Consumer Example'),
|
|
),
|
|
body: const Center(
|
|
child: Column(
|
|
mainAxisAlignment: MainAxisAlignment.center,
|
|
children: [
|
|
CounterConsumer(),
|
|
CounterConsumer2(),
|
|
CounterConsumer3(),
|
|
],
|
|
),
|
|
),
|
|
),
|
|
);
|
|
}
|
|
}
|
|
|
|
class Counter extends ChangeNotifier {
|
|
int _count = 0;
|
|
int get count => _count;
|
|
|
|
void increment() {
|
|
_count++;
|
|
notifyListeners();
|
|
}
|
|
}
|
|
|
|
class CounterConsumer extends StatelessWidget {
|
|
const CounterConsumer({super.key});
|
|
|
|
@override
|
|
Widget build(BuildContext context) {
|
|
return Consumer<Counter>(
|
|
builder: (context, counter, child) {
|
|
return Column(
|
|
children: [
|
|
Text('Count: ${counter.count}'),
|
|
ElevatedButton(
|
|
onPressed: counter.increment,
|
|
child: const Text('Increment'),
|
|
),
|
|
],
|
|
);
|
|
},
|
|
);
|
|
}
|
|
}
|
|
|
|
class CounterConsumer2 extends StatelessWidget {
|
|
const CounterConsumer2({super.key});
|
|
|
|
@override
|
|
Widget build(BuildContext context) {
|
|
return Consumer2<Counter, Counter>(
|
|
builder: (context, counter1, counter2, child) {
|
|
return Text('Same counter: ${counter1.count} = ${counter2.count}');
|
|
},
|
|
);
|
|
}
|
|
}
|
|
|
|
class CounterConsumer3 extends StatelessWidget {
|
|
const CounterConsumer3({super.key});
|
|
|
|
@override
|
|
Widget build(BuildContext context) {
|
|
return Consumer<Counter>(
|
|
builder: (context, counter, child) {
|
|
return Column(
|
|
children: [
|
|
child!,
|
|
Text('Count: ${counter.count}'),
|
|
],
|
|
);
|
|
},
|
|
child: const Text('This widget will not rebuild'),
|
|
);
|
|
}
|
|
}
|