import 'package:flutter/cupertino.dart';

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

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

  @override
  Widget build(BuildContext context) {
    return CupertinoApp(
      theme: CupertinoThemeData(),
      home: FirstPage(),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      child: CustomScrollView(
        slivers: [
          CupertinoSliverNavigationBar.search(
            stretch: true,
            previousPageTitle: "Page 1",
            trailing: CupertinoButton(
                padding: EdgeInsets.zero,
                alignment: Alignment.center,
                child: Icon(CupertinoIcons.add_circled),
                onPressed: () {}),
            searchField: Builder(builder: (context) {
              return CupertinoSearchTextField(
                  autofocus: true,
                  suffixMode: OverlayVisibilityMode.always,
                  suffixIcon: Icon(
                    CupertinoIcons.mic_solid,
                  ));
            }),
            largeTitle: Text('iPhone'),
          ),
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
                return GestureDetector(
                  onTap: () => Navigator.of(context).push(
                    CupertinoPageRoute(
                      builder: (context) => SecondPage(),
                    ),
                  ),
                  child: CupertinoListTile(
                    title: Text('Entry $index'),
                  ),
                );
              },
              childCount: 20,
            ),
          ),
        ],
      ),
    );
  }
}

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

  @override
  Widget build(BuildContext context) {
    return CupertinoPageScaffold(
      child: CustomScrollView(
        slivers: [
          CupertinoSliverNavigationBar.search(
            stretch: true,
            previousPageTitle: 'iPhone',
            searchField: CupertinoSearchTextField(),
            largeTitle: Text('Third Page'),
          ),
          SliverList(
            delegate: SliverChildBuilderDelegate(
              (BuildContext context, int index) {
                return CupertinoListTile(
                  title: Text('Entry $index'),
                );
              },
              childCount: 20,
            ),
          ),
        ],
      ),
    );
  }
}