packages.dart/packages/flutter_whatsnew/example/lib/main.dart

import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
import 'package:flutter_whatsnew/flutter_whatsnew.dart';

import 'dart:io' show Platform;
import 'package:flutter/foundation.dart';

// The existing imports
// !! Keep your existing impots here !!

/// main is entry point of Flutter application
void main() {
  // Desktop platforms aren't a valid platform.
  if (!kIsWeb) _setTargetPlatformForDesktop();
  return runApp(MyApp());
}

/// If the current platform is desktop, override the default platform to
/// a supported platform (iOS for macOS, Android for Linux and Windows).
/// Otherwise, do nothing.
void _setTargetPlatformForDesktop() {
  TargetPlatform targetPlatform;
  if (Platform.isMacOS) {
    targetPlatform = TargetPlatform.iOS;
  } else if (Platform.isLinux || Platform.isWindows) {
    targetPlatform = TargetPlatform.android;
  }
  if (targetPlatform != null) {
    debugDefaultTargetPlatformOverride = targetPlatform;
  }
}

class MyApp extends StatelessWidget {
  final double textScaleFactor = 1.0;

  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      debugShowCheckedModeBanner: false,
      home: HomeScreen(textScaleFactor: textScaleFactor),
    );
  }
}

class HomeScreen extends StatelessWidget {
  const HomeScreen({
    Key key,
    @required this.textScaleFactor,
  }) : super(key: key);

  final double textScaleFactor;

  @override
  Widget build(BuildContext context) {
    return ScheduledWhatsNewPage(
      details: WhatsNewPage.changelog(),
      delay: Duration(seconds: 7),
      child: Scaffold(
        body: SafeArea(
          child: Center(
            child: Column(
              mainAxisAlignment: MainAxisAlignment.center,
              crossAxisAlignment: CrossAxisAlignment.center,
              children: <Widget>[
                ElevatedButton(
                  child: Text("Show Changelog"),
                  onPressed: () {
                    Navigator.push(
                      context,
                      MaterialPageRoute(
                        builder: (context) => WhatsNewPage.changelog(
                          title: Text(
                            "What's New",
                            textScaleFactor: textScaleFactor,
                            textAlign: TextAlign.center,
                            style: const TextStyle(
                              // Text Style Needed to Look like iOS 11
                              fontSize: 22.0,
                              fontWeight: FontWeight.bold,
                            ),
                          ),
                          buttonText: Text(
                            'Continue',
                            textScaleFactor: textScaleFactor,
                            style: const TextStyle(color: Colors.white),
                          ),
                        ),
                        fullscreenDialog: true,
                      ),
                    );
                  },
                ),
                Container(height: 50.0),
                ElevatedButton(
                  child: Text("Show Changes"),
                  onPressed: () {
                    Navigator.push(
                      context,
                      MaterialPageRoute(
                        builder: (context) => WhatsNewPage(
                          title: Text(
                            "What's New",
                            textScaleFactor: textScaleFactor,
                            textAlign: TextAlign.center,
                            style: const TextStyle(
                              // Text Style Needed to Look like iOS 11
                              fontSize: 22.0,
                              fontWeight: FontWeight.bold,
                            ),
                          ),
                          buttonText: Text(
                            'Continue',
                            textScaleFactor: textScaleFactor,
                            style: const TextStyle(color: Colors.white),
                          ),
                          // Create a List of WhatsNewItem for use in the Whats New Page
                          // Create as many as you need, it will be scrollable
                          items: <ListTile>[
                            ListTile(
                              leading: const Icon(Icons.color_lens),
                              title: Text(
                                'Dark Theme',
                                textScaleFactor: textScaleFactor,
                              ), //Title is the only Required Item
                              subtitle: Text(
                                'Black and grey theme (Tap to Change)',
                                textScaleFactor: textScaleFactor,
                              ),
                              onTap: () {
                                // You Can Navigate to Locations in the App
                                Navigator.of(context).pushNamed("/settings");
                              },
                            ),
                            ListTile(
                              leading: const Icon(Icons.map),
                              title: Text(
                                'Google Maps',
                                textScaleFactor: textScaleFactor,
                              ),
                              subtitle: Text(
                                'Open Address Links in Google Maps instead of Apple Maps (Tap to Change)',
                                textScaleFactor: textScaleFactor,
                              ),
                              onTap: () {
                                // You Can Navigate to Locations in the App
                                Navigator.of(context).pushNamed("/settings");
                              },
                            ),
                            ListTile(
                              leading: const Icon(Icons.notifications_active),
                              title: Text(
                                'Push Notifications',
                                textScaleFactor: textScaleFactor,
                              ),
                              subtitle: Text(
                                'Stay tuned for important information that can be pushed to you',
                                textScaleFactor: textScaleFactor,
                              ),
                              onTap: () {
                                WhatsNewPage.showDetailPopUp(
                                  context,
                                  'Info',
                                  "You can turn off push notifications any time in your application settings.",
                                );
                              },
                            ),
                          ], //Required
                        ),
                        fullscreenDialog: true,
                      ),
                    );
                  },
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}