Cupertino scrolling app bar

main.dart

import 'package:flutter/cupertino.dart';

void main() => runApp(const MyApp());

class MyApp extends StatelessWidget {
  const MyApp({super.key});

  @override
  Widget build(BuildContext context) {
    const title = 'Floating App Bar';

    return CupertinoApp(
      title: title,
      home: CupertinoPageScaffold(
        // No appbar provided to the Scaffold, only a body with a
        // CustomScrollView.
        child: CustomScrollView(
          slivers: [
            // Add the app bar to the CustomScrollView.
            CupertinoSliverNavigationBar(
              // Provide a standard title.
              largeTitle: Text(title),
            ),
            // Next, create a SliverList
            SliverList(
              // Use a delegate to build items as they're scrolled on screen.
              delegate: SliverChildBuilderDelegate(
                // The builder function returns a ListTile with a title that
                // displays the index of the current item.
                (context, index) => CupertinoListTile(title: Text('Item #$index')),
                // Builds 1000 ListTiles
                childCount: 1000,
              ),
            ),
          ],
        ),
      ),
    );
  }
}