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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.
import 'package:flutter/material.dart';
/// Flutter code sample for [NavigationBar].
void main() => runApp(const NavigationBarApp());
class NavigationBarApp extends StatelessWidget {
const NavigationBarApp({super.key});
@override
Widget build(BuildContext context) {
return const MaterialApp(home: NavigationExample());
}
}
class NavigationExample extends StatefulWidget {
const NavigationExample({super.key});
@override
State<NavigationExample> createState() => _NavigationExampleState();
}
class _NavigationExampleState extends State<NavigationExample> {
int currentPageIndex = 0;
NavigationDestinationLabelBehavior labelBehavior = NavigationDestinationLabelBehavior.alwaysShow;
@override
Widget build(BuildContext context) {
return Scaffold(
bottomNavigationBar: NavigationBar(
labelBehavior: labelBehavior,
selectedIndex: currentPageIndex,
onDestinationSelected: (int index) {
setState(() {
currentPageIndex = index;
});
},
destinations: const <Widget>[
NavigationDestination(
icon: Icon(Icons.explore),
label: 'Explore',
),
NavigationDestination(
icon: Icon(Icons.commute),
label: 'Commute',
),
NavigationDestination(
selectedIcon: Icon(Icons.bookmark),
icon: Icon(Icons.bookmark_border),
label: 'Saved',
),
],
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text('Label behavior: ${labelBehavior.name}'),
const SizedBox(height: 10),
OverflowBar(
spacing: 10.0,
children: <Widget>[
ElevatedButton(
onPressed: () {
setState(() {
labelBehavior = NavigationDestinationLabelBehavior.alwaysShow;
});
},
child: const Text('alwaysShow'),
),
ElevatedButton(
onPressed: () {
setState(() {
labelBehavior = NavigationDestinationLabelBehavior.onlyShowSelected;
});
},
child: const Text('onlyShowSelected'),
),
ElevatedButton(
onPressed: () {
setState(() {
labelBehavior = NavigationDestinationLabelBehavior.alwaysHide;
});
},
child: const Text('alwaysHide'),
),
],
),
],
),
),
);
}
}