samples/navigation_and_routing/lib/src/screens/settings.dart

// Copyright 2021, the Flutter project authors. Please see the AUTHORS file
// for details. 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 'package:url_launcher/link.dart';

import '../auth/auth.dart';

class SettingsScreen extends StatefulWidget {
  const SettingsScreen({Key? key}) : super(key: key);

  @override
  _SettingsScreenState createState() => _SettingsScreenState();
}

class _SettingsScreenState extends State<SettingsScreen> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: SafeArea(
        child: SingleChildScrollView(
          child: Align(
            alignment: Alignment.topCenter,
            child: ConstrainedBox(
              constraints: const BoxConstraints(maxWidth: 400),
              child: const Card(
                child: Padding(
                  padding: EdgeInsets.symmetric(vertical: 18, horizontal: 12),
                  child: SettingsContent(),
                ),
              ),
            ),
          ),
        ),
      ),
    );
  }
}

class SettingsContent extends StatelessWidget {
  const SettingsContent({
    Key? key,
  }) : super(key: key);

  @override
  Widget build(BuildContext context) {
    return Column(
      children: [
        ...[
          Text(
            'Settings',
            style: Theme.of(context).textTheme.headline4,
          ),
          ElevatedButton(
            onPressed: () {
              BookstoreAuthScope.of(context)!.signOut();
            },
            child: const Text('Sign out'),
          ),
          Link(
            uri: Uri.parse('/book/0'),
            builder: (context, followLink) {
              return TextButton(
                child: const Text('Go directly to /book/0'),
                onPressed: followLink,
              );
            },
          ),
          Link(
            uri: Uri.parse('/author/0'),
            builder: (context, followLink) {
              return TextButton(
                child: const Text('Go directly to /author/0'),
                onPressed: followLink,
              );
            },
          ),
        ].map((w) => Padding(padding: const EdgeInsets.all(8), child: w)),
        TextButton(
          onPressed: () => showDialog<String>(
            context: context,
            builder: (context) => AlertDialog(
              title: const Text('Alert!'),
              content: const Text('The alert description goes here.'),
              actions: <Widget>[
                TextButton(
                  onPressed: () => Navigator.pop(context, 'Cancel'),
                  child: const Text('Cancel'),
                ),
                TextButton(
                  onPressed: () => Navigator.pop(context, 'OK'),
                  child: const Text('OK'),
                ),
              ],
            ),
          ),
          child: const Text('Show Dialog'),
        )
      ],
    );
  }
}