flutter/dev/a11y_assessments/lib/use_cases/app_bar.dart

// 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';

import 'use_cases.dart';

class AppBarUseCase extends UseCase {
  @override
  String get name => 'AppBar';

  @override
  String get route => '/app-bar';

  @override
  Widget build(BuildContext context) => const MainWidget();
}

class MainWidget extends StatefulWidget {
  const MainWidget({super.key});

  @override
  State<MainWidget> createState() => MainWidgetState();
}

class MainWidgetState extends State<MainWidget> {
  int currentIndex = 0;

  void _onChanged(int? value) {
    setState(() {
      currentIndex = value!;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: <PreferredSizeWidget>[
        AppBar(
          backgroundColor: Theme.of(context).colorScheme.inversePrimary,
          title: Semantics(headingLevel: 1, child: const Text('AppBar')),
        ),
        AppBar(
          backgroundColor: Theme.of(context).colorScheme.inversePrimary,
          title: Semantics(headingLevel: 1, child: const Text('AppBar')),
          actions: <Widget>[
            IconButton(
              icon: const Icon(Icons.add_alert),
              tooltip: 'Show Snackbar',
              onPressed: () {
                ScaffoldMessenger.of(context).showSnackBar(
                    const SnackBar(content: Text('This is a snackbar')));
              },
            ),
            IconButton(
              icon: const Icon(Icons.navigate_next),
              tooltip: 'Go to the next page',
              onPressed: () {
                Navigator.push(context, MaterialPageRoute<void>(
                  builder: (BuildContext context) {
                    return Scaffold(
                      appBar: AppBar(
                        backgroundColor:
                            Theme.of(context).colorScheme.inversePrimary,
          title: Semantics(headingLevel: 1, child: const Text('Next Page')),
                      ),
                      body: const Center(
                        child: Text(
                          'This is the next page',
                          style: TextStyle(fontSize: 24),
                        ),
                      ),
                    );
                  },
                ));
              },
            ),
          ],
        ),
        AppBar(
          backgroundColor: Theme.of(context).colorScheme.inversePrimary,
          title: Semantics(headingLevel: 1, child: const Text('AppBar')),
          actions: <Widget>[
            TextButton(
              onPressed: () {},
              child: const Text('Action 1'),
            ),
            TextButton(
              onPressed: () {},
              child: const Text('Action 2'),
            ),
          ],
        ),
      ][currentIndex],
      body: ListView(
        children: <Widget>[
          RadioListTile<int>(
            title: const Text('1. Simple app bar'),
            value: 0,
            groupValue: currentIndex,
            onChanged: _onChanged,
          ),
          RadioListTile<int>(
            title: const Text('2. App bar with actions'),
            value: 1,
            groupValue: currentIndex,
            onChanged: _onChanged,
          ),
          RadioListTile<int>(
            title: const Text('3. App bar with text buttons'),
            value: 2,
            groupValue: currentIndex,
            onChanged: _onChanged,
          ),
        ],
      ),
    );
  }
}