import 'package:flutter/material.dart';

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

  @override
  State<StatefulWidget> createState() => _SearchPageState();
}

class _SearchPageState extends State<SearchPage> {
  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: const Text('搜索效果'),
        actions: <Widget>[
          IconButton(
            onPressed: () {
              showSearch(context: context, delegate: SearchBarDelegate());
            },
            icon: const Icon(Icons.search),
          ),
        ],
      ),
      body: const Center(child: Text('test search')),
    );
  }
}

class SearchBarDelegate extends SearchDelegate<String> {
  @override
  List<Widget> buildActions(BuildContext context) {
    return [
      IconButton(
        icon: const Icon(Icons.clear),
        onPressed: () {
          query = "";
          showSuggestions(context);
        },
      ),
    ];
  }

  @override
  Widget buildLeading(BuildContext context) {
    return IconButton(
      icon: AnimatedIcon(
        icon: AnimatedIcons.menu_arrow,
        progress: transitionAnimation,
      ),
      onPressed: () {
        if (query.isEmpty) {
          close(context, '');
        } else {
          query = "";
          showSuggestions(context);
        }
      },
    );
  }

  @override
  Widget buildResults(BuildContext context) {
    return const Center(
      child: Text('buildResults'),
    );
  }

  @override
  Widget buildSuggestions(BuildContext context) {
    return const Center(
      child: Text('buildSuggestions'),
    );
  }

  @override
  ThemeData appBarTheme(BuildContext context) {
    final ThemeData theme = Theme.of(context);
    return theme.copyWith(
      primaryColor: Colors.white,
      primaryIconTheme: theme.primaryIconTheme.copyWith(color: Colors.grey),
      primaryTextTheme: theme.textTheme,
    );
  }
}