main.dart

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

void main() {
  runApp(const MyApp());
}

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

  // This widget is the root of your application.
  @override
  Widget build(BuildContext context) {
    return MaterialApp(
      home: Scaffold(
        body: CustomScrollView(
          slivers: [
            const CupertinoSliverNavigationBar(
              padding: EdgeInsetsDirectional.only(end: 15),
              largeTitle: Text('Search'),
            ),
            SliverToBoxAdapter(
              child: SingleChildScrollView(
                scrollDirection: Axis.horizontal,
                child: SizedBox(
                    width: 1600,
                    child: ListView.builder(
                        itemCount: 100,
                        shrinkWrap: true,
                        itemBuilder: (BuildContext context, int index) {
                          if (index == 0) {
                            return Container(
                              width: 1600,
                              padding: const EdgeInsets.all(5),
                              color: Colors.redAccent.shade100,
                              child: const Text('foo'),
                            );
                          } else {
                            return Container(
                              width: 1600,
                              padding: const EdgeInsets.all(5),
                              color: Colors.blueAccent.shade100,
                              child: const Text('bar'),
                            );
                          }
                        })),
              ),
            ),
          ],
        ),
      ),
    );
  }
}