Flutter，如何在sqflite数据库中即时搜索？

import 'package:flutter/material.dart';
import 'package:sqflite/sqflite.dart';
import 'package:path/path.dart';

class SearchPage extends StatefulWidget {
  @override
  _SearchPageState createState() => _SearchPageState();
}

class _SearchPageState extends State<SearchPage> {
  Database _database;
  List<String> _searchResults = [];

  @override
  void initState() {
    super.initState();
    _openDatabase();
  }

  Future<void> _openDatabase() async {
    final databasePath = await getDatabasesPath();
    final path = join(databasePath, 'my_database.db');
    _database = await openDatabase(path, version: 1,
        onCreate: (Database db, int version) async {
      await db.execute('CREATE TABLE IF NOT EXISTS my_table (id INTEGER PRIMARY KEY, name TEXT)');
    });
  }

  Future<List<String>> _search(String keyword) async {
    final List<Map<String, dynamic>> maps = await _database.query(
      'my_table',
      where: 'name LIKE ?',
      whereArgs: ['%$keyword%'],
    );

    return List.generate(maps.length, (i) {
      return maps[i]['name'] as String;
    });
  }

  void _onSearchTextChanged(String text) async {
    final results = await _search(text);
    setState(() {
      _searchResults = results;
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: Text('Search'),
      ),
      body: Column(
        children: [
          TextField(
            onChanged: _onSearchTextChanged,
            decoration: InputDecoration(
              hintText: 'Search...',
            ),
          ),
          Expanded(
            child: ListView.builder(
              itemCount: _searchResults.length,
              itemBuilder: (context, index) {
                return ListTile(
                  title: Text(_searchResults[index]),
                );
              },
            ),
          ),
        ],
      ),
    );
  }
}