Expo React Native JavaScript Best Practices
Guidelines for building high-quality Expo React Native applications with JavaScript, focusing on clean code, modularity, and performance.
Code Style and Structure Clean, Readable Code: Ensure your code is easy to read and understand. Use descriptive names for variables and functions. Functional Components: Prefer functional components with hooks (useState, useEffect) over class components Component Modularity: Break components into smaller, reusable pieces with single responsibility Feature-Based Organization: Group related components, hooks, and styles into feature directories (e.g., user-profile, chat-screen) Naming Conventions Variables and Functions: Use camelCase (e.g., isFetchingData, handleUserInput) Components: Use PascalCase (e.g., UserProfile, ChatScreen) Directories: Use lowercase hyphenated names (e.g., user-profile, chat-screen) JavaScript Usage Minimize global variables to prevent unintended side effects Leverage ES6+ features like arrow functions, destructuring, and template literals to write concise code Use PropTypes for type checking if not using TypeScript Performance Optimization Avoid unnecessary state updates; use local state when needed Apply React.memo() to prevent unnecessary re-renders Optimize FlatList with the following props: removeClippedSubviews maxToRenderPerBatch windowSize Avoid anonymous functions in renderItem or event handlers UI and Styling Use StyleSheet.create() for consistent styling or Styled Components for dynamic styles Ensure responsive design across screen sizes and orientations Use optimized image libraries like react-native-fast-image Best Practices Follow React Native's threading model for smooth UI performance Use Expo's EAS Build and OTA updates for deployment Expo Router: Use Expo Router for file-based routing in your React Native app. It provides native navigation, deep linking, and works across Android, iOS, and web