How to listen to page changes in nextjs

In Next.js, listening for page route changes can be achieved through multiple methods, but the most common approach is to use the Router object provided by Next.js. This enables you to monitor route events such as route change starts, route change completes, and route change errors. Next, I will provide a detailed explanation of how to use these events to track page route changes.

Using Router Event Listeners

Next.js utilizes the Router from the next/router module to manage route events. Here are some commonly used events:

• routeChangeStart: Triggered when the route change begins
• routeChangeComplete: Triggered when the route change completes
• routeChangeError: Triggered when a route change attempt fails
• beforeHistoryChange: Triggered before the browser history changes

Example Code

Here is an example of how to use these events within a component:

javascript
import { useEffect } from 'react';
import Router from 'next/router';

function MyApp() {
  useEffect(() => {
    const handleRouteChange = (url) => {
      console.log('App is changing to: ', url);
    }

    Router.events.on('routeChangeStart', handleRouteChange);
    Router.events.on('routeChangeComplete', handleRouteChange);
    Router.events.on('routeChangeError', handleRouteChange);

    // Clean up event listeners
    return () => {
      Router.events.off('routeChangeStart', handleRouteChange);
      Router.events.off('routeChangeComplete', handleRouteChange);
      Router.events.off('routeChangeError', handleRouteChange);
    };
  }, []);

  return <div>Welcome to Next.js!</div>;
}

export default MyApp;

In this example, we use the useEffect hook to ensure event listeners are added when the component mounts and removed when it unmounts. This is a best practice to prevent memory leaks.

Use Cases

Listening for route changes can be applied to various scenarios, such as:

• Tracking page visits (e.g., for analytics)
• Triggering animations or transitions based on route changes
• Conditionally rendering components or page titles

Conclusion

By leveraging the Router events from next/router, you can flexibly handle various route change scenarios. This is a valuable feature when building complex single-page applications (SPAs), as it enhances user experience and application performance.