react-native

React Native Skill

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Project Structure

project/
├── src/
│   ├── core/                   # Pure business logic (no React)
│   │   ├── types.ts
│   │   └── services/
│   ├── components/             # Reusable UI components
│   │   ├── Button/
│   │   │   ├── Button.tsx
│   │   │   ├── Button.test.tsx
│   │   │   └── index.ts
│   │   └── index.ts            # Barrel export
│   ├── screens/                # Screen components
│   │   ├── Home/
│   │   │   ├── HomeScreen.tsx
│   │   │   ├── useHome.ts      # Screen-specific hook
│   │   │   └── index.ts
│   │   └── index.ts
│   ├── navigation/             # Navigation configuration
│   ├── hooks/                  # Shared custom hooks
│   ├── store/                  # State management
│   └── utils/                  # Utilities
├── __tests__/
├── android/
├── ios/
└── CLAUDE.md

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Component Patterns

Functional Components Only

// Good - simple, testable
interface ButtonProps {
  label: string;
  onPress: () => void;
  disabled?: boolean;
}

export function Button({ label, onPress, disabled = false }: ButtonProps): JSX.Element {
  return (
    <Pressable onPress={onPress} disabled={disabled}>
      <Text>{label}</Text>
    </Pressable>
  );
}

Extract Logic to Hooks

// useHome.ts - all logic here
export function useHome() {
  const [items, setItems] = useState<Item[]>([]);
  const [loading, setLoading] = useState(false);

  const refresh = useCallback(async () => {
    setLoading(true);
    const data = await fetchItems();
    setItems(data);
    setLoading(false);
  }, []);

  return { items, loading, refresh };
}

// HomeScreen.tsx - pure presentation
export function HomeScreen(): JSX.Element {
  const { items, loading, refresh } = useHome();
  
  return (
    <ItemList items={items} loading={loading} onRefresh={refresh} />
  );
}

Props Interface Always Explicit

// Always define props interface, even if simple
interface ItemCardProps {
  item: Item;
  onPress: (id: string) => void;
}

export function ItemCard({ item, onPress }: ItemCardProps): JSX.Element {
  ...
}