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// Copyright 2014 The Flutter Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
/// Flutter code sample for [PageStorage].
import 'package:flutter/material.dart';
void main() => runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({super.key});
@override
Widget build(BuildContext context) {
return const MaterialApp(
home: MyHomePage(),
);
}
}
class MyHomePage extends StatefulWidget {
const MyHomePage({super.key});
@override
State<MyHomePage> createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
final List<Widget> pages = const <Widget>[
ColorBoxPage(
key: PageStorageKey<String>('pageOne'),
),
ColorBoxPage(
key: PageStorageKey<String>('pageTwo'),
),
];
int currentTab = 0;
final PageStorageBucket _bucket = PageStorageBucket();
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Persistence Example'),
),
body: PageStorage(
bucket: _bucket,
child: pages[currentTab],
),
bottomNavigationBar: BottomNavigationBar(
currentIndex: currentTab,
onTap: (int index) {
setState(() {
currentTab = index;
});
},
items: const <BottomNavigationBarItem>[
BottomNavigationBarItem(
icon: Icon(Icons.home),
label: 'page 1',
),
BottomNavigationBarItem(
icon: Icon(Icons.settings),
label: 'page2',
),
],
),
);
}
}
class ColorBoxPage extends StatelessWidget {
const ColorBoxPage({super.key});
@override
Widget build(BuildContext context) {
return ListView.builder(
itemExtent: 250.0,
itemBuilder: (BuildContext context, int index) => Container(
padding: const EdgeInsets.all(10.0),
child: Material(
color: index.isEven ? Colors.cyan : Colors.deepOrange,
child: Center(
child: Text(index.toString()),
),
),
),
);
}
}