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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 OrderedTraversalPolicy
import 'package:flutter/material.dart';
void main() => runApp(const MyApp());
class MyApp extends StatelessWidget {
const MyApp({Key? key}) : super(key: key);
static const String _title = 'Flutter Code Sample';
@override
Widget build(BuildContext context) {
return MaterialApp(
title: _title,
home: Scaffold(
appBar: AppBar(title: const Text(_title)),
body: const Center(
child: MyStatelessWidget(),
),
),
);
}
}
class DemoButton extends StatelessWidget {
const DemoButton({
Key? key,
required this.name,
this.autofocus = false,
required this.order,
}) : super(key: key);
final String name;
final bool autofocus;
final double order;
void _handleOnPressed() {
debugPrint('Button $name pressed.');
debugDumpFocusTree();
}
@override
Widget build(BuildContext context) {
return FocusTraversalOrder(
order: NumericFocusOrder(order),
child: TextButton(
autofocus: autofocus,
onPressed: () => _handleOnPressed(),
child: Text(name),
),
);
}
}
class MyStatelessWidget extends StatelessWidget {
const MyStatelessWidget({Key? key}) : super(key: key);
@override
Widget build(BuildContext context) {
return FocusTraversalGroup(
policy: OrderedTraversalPolicy(),
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: const <Widget>[
DemoButton(name: 'Six', order: 6),
],
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: const <Widget>[
DemoButton(name: 'Five', order: 5),
DemoButton(name: 'Four', order: 4),
],
),
Row(
mainAxisAlignment: MainAxisAlignment.center,
children: const <Widget>[
DemoButton(name: 'Three', order: 3),
DemoButton(name: 'Two', order: 2),
DemoButton(name: 'One', order: 1, autofocus: true),
],
),
],
),
);
}
}