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Debugging & Inspector

? Debugging & Inspector

? Quick Overview

Debugging in React Native helps developers identify, inspect, and fix issues in JavaScript logic, UI rendering, network calls, and native behavior. The built-in Debug Menu and Inspector tools provide powerful insights during development.

? Key Concepts

  • Debug Menu (Developer Menu)
  • Element Inspector
  • Console logging
  • Remote JS debugging
  • Network & performance inspection

? Syntax / Theory

React Native debugging relies on JavaScript runtime inspection, UI hierarchy analysis, and runtime logs. The Debug Menu can be opened using gestures or shortcuts depending on platform.

? Code Example(s)

? View Code Example
// Basic console debugging in React Native
import { View, Text } from 'react-native';

export default function App() {
console.log("App component rendered");
return (

Debugging Example

);
}

? Live Output / Explanation

The message “App component rendered” will appear in the Metro console or debugger whenever the component renders, helping track render cycles.

? Interactive Example / Inspector Flow

? React Native Simulator
MyApp
Welcome!
Open the Dev Menu to start debugging.
Tap to Log
React Native Dev Menu
? Reload
? Toggle Inspector
? Debug JS Remotely
Cancel
[Metro] Bundling complete 100.0% (120ms)
[App] App component mounted

? Use Cases

  • Finding layout issues using Inspector
  • Tracking state changes with console logs
  • Debugging API calls and responses
  • Identifying unnecessary re-renders

✅ Tips & Best Practices

  • Remove console logs before production builds
  • Use meaningful log messages
  • Combine Inspector with Flexbox debugging
  • Restart Metro if logs behave unexpectedly

? Try It Yourself

  1. Click "Shake Device" above to open the Developer Menu.
  2. Select "Toggle Inspector".
  3. Hover over elements on the phone screen to see their names in the console.
  4. Click elements to "inspect" them (logs details).