Flutter vs React Native 比較

// Flutter - アニメーション付き商品カード
import 'package:flutter/material.dart';

class ProductCard extends StatefulWidget {
  final String productName;
  final double price;
  final String imageUrl;

  const ProductCard({
    super.key,
    required this.productName,
    required this.price,
    required this.imageUrl,
  });

  @override
  State<ProductCard> createState() => _ProductCardState();
}

class _ProductCardState extends State<ProductCard>
    with SingleTickerProviderStateMixin {
  late AnimationController _controller;
  late Animation<double> _scaleAnimation;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: const Duration(milliseconds: 200),
      vsync: this,
    );
    _scaleAnimation = Tween<double>(begin: 1.0, end: 0.95).animate(
      CurvedAnimation(parent: _controller, curve: Curves.easeInOut),
    );
  }

  @override
  Widget build(BuildContext context) {
    return GestureDetector(
      onTapDown: (_) => _controller.forward(),
      onTapUp: (_) => _controller.reverse(),
      child: AnimatedBuilder(
        animation: _scaleAnimation,
        builder: (context, child) => Transform.scale(
          scale: _scaleAnimation.value,
          child: Card(
            child: Column(
              children: [
                Image.network(widget.imageUrl, height: 200, fit: BoxFit.cover),
                Padding(
                  padding: const EdgeInsets.all(16),
                  child: Row(
                    mainAxisAlignment: MainAxisAlignment.spaceBetween,
                    children: [
                      Text(widget.productName, style: Theme.of(context).textTheme.titleMedium),
                      Text('₺${widget.price.toStringAsFixed(2)}',
                          style: const TextStyle(fontWeight: FontWeight.bold, color: Colors.green)),
                    ],
                  ),
                ),
              ],
            ),
          ),
        ),
      ),
    );
  }
}

// React Native - アニメーション付き商品カード
import React, { useRef } from 'react';
import {
  Animated,
  TouchableWithoutFeedback,
  Image,
  Text,
  View,
  StyleSheet,
} from 'react-native';

interface ProductCardProps {
  productName: string;
  price: number;
  imageUrl: string;
}

export function ProductCard({ productName, price, imageUrl }: ProductCardProps) {
  const scaleAnim = useRef(new Animated.Value(1)).current;

  const handlePressIn = () => {
    Animated.spring(scaleAnim, {
      toValue: 0.95,
      useNativeDriver: true,
    }).start();
  };

  const handlePressOut = () => {
    Animated.spring(scaleAnim, {
      toValue: 1,
      friction: 3,
      useNativeDriver: true,
    }).start();
  };

  return (
    <TouchableWithoutFeedback onPressIn={handlePressIn} onPressOut={handlePressOut}>
      <Animated.View style={[styles.card, { transform: [{ scale: scaleAnim }] }]}>
        <Image source={{ uri: imageUrl }} style={styles.image} resizeMode="cover" />
        <View style={styles.info}>
          <Text style={styles.name}>{productName}</Text>
          <Text style={styles.price}>₺{price.toFixed(2)}</Text>
        </View>
      </Animated.View>
    </TouchableWithoutFeedback>
  );
}

const styles = StyleSheet.create({
  card: { borderRadius: 12, overflow: 'hidden', backgroundColor: 'white', elevation: 4 },
  image: { width: '100%', height: 200 },
  info: { flexDirection: 'row', justifyContent: 'space-between', padding: 16 },
  name: { fontSize: 16, fontWeight: '600' },
  price: { fontSize: 16, fontWeight: '700', color: '#22c55e' },
});