Mobile-First Development with React Native

React Native: One Codebase, Multiple Platforms

React Native enables developers to build native mobile applications using React and JavaScript, sharing code between iOS and Android platforms.

Getting Started with React Native

Development Environment Setup

• Install Node.js and npm/yarn
• Set up React Native CLI or Expo CLI
• Configure Android Studio and Xcode
• Set up device emulators or use physical devices

Project Structure

A typical React Native project includes:

• src/ - Application source code
• components/ - Reusable UI components
• screens/ - Screen components
• navigation/ - Navigation configuration
• services/ - API and business logic
• utils/ - Helper functions

Core React Native Concepts

1. Native Components

React Native provides platform-specific components that compile to native UI elements:

• View - Container component (like div)
• Text - Text display component
• ScrollView - Scrollable container
• FlatList - Efficient list rendering
• TouchableOpacity - Touchable wrapper

2. Styling with StyleSheet

React Native uses a subset of CSS properties with camelCase naming:

const styles = StyleSheet.create({
  container: {
    flex: 1,
    justifyContent: 'center',
    alignItems: 'center',
    backgroundColor: '#f5f5f5'
  }
})

3. Navigation

Use React Navigation for handling navigation between screens with native performance.

Performance Optimization

1. List Optimization

• Use FlatList instead of ScrollView for large datasets
• Implement getItemLayout for known item dimensions
• Use keyExtractor for efficient re-rendering

2. Image Optimization

• Use appropriate image formats and sizes
• Implement lazy loading for images
• Cache images for better performance

3. Memory Management

• Remove event listeners in cleanup
• Use React.memo for expensive components
• Optimize state updates and re-renders

Native Module Integration

When React Native doesn't provide the functionality you need, you can write native modules or use existing ones from the community.

Testing React Native Apps

• Unit testing with Jest
• Component testing with React Native Testing Library
• End-to-end testing with Detox
• Manual testing on real devices

Deployment

Learn the process of building and deploying your app to the App Store and Google Play Store, including code signing and release management.