import 'package:flutter/material.dart'; import 'package:sqflite/sqflite.dart'; import 'db_helper.dart'; import 'product.dart'; class ProductProvider with ChangeNotifier { List _products = []; List get products => _products; Future fetchProducts() async { final db = await DbHelper().database; final List> maps = await db.query('products'); _products = List.generate(maps.length, (i) { return Product.fromMap(maps[i]); }); notifyListeners(); } Future addProduct(Product product) async { final db = await DbHelper().database; await db.insert('products', product.toMap()); fetchProducts(); } // 追加の CRUD メソッドを実装 }