Logo Questions Linux Laravel Mysql Ubuntu Git Menu
 

NextJS: How can I use a loading component instead of nprogress?

Is it possible to use a <Loading /> component in NextJS instead of nprogress? I'm thinking you would need to access some high level props like pageProps from the router events so you can toggle the loading state and then conditionally output a loading component but I don't see a way to do this...

For example,

Router.events.on("routeChangeStart", (url, pageProps) => {
  pageProps.loading = true;
});

and in the render

const { Component, pageProps } = this.props;

return pageProps.loading ? <Loading /> : <Page />;

But of course, routeChangeStart doesn't pass in pageProps.

like image 936
tsdexter Avatar asked Dec 14 '22 13:12

tsdexter


2 Answers

Yes, it is possible to use another component to handle loading instead of nProgress. I had a similar question, and found the solution below working out for me.

It makes sense to do all this in ./pages/_app.js, because according to the documentation that can help with persisting layout and state between pages. You can initiate the Router events on the lifecycle method componentDidMount. It's important to note that _app.js only mounts once, but initiating Router events will still work here. This will allow you to be able to set state.

Below is an example of how this all comes together:

import React, { Fragment } from 'react';
import App from 'next/app';
import Head from 'next/head';
import Router from 'next/router';

class MyApp extends App {
  state = { isLoading: false }

  componentDidMount() {
    // Logging to prove _app.js only mounts once,
    // but initializing router events here will also accomplishes
    // goal of setting state on route change
    console.log('MOUNT');

    Router.events.on('routeChangeStart', () => {
      this.setState({ isLoading: true });
    });

    Router.events.on('routeChangeComplete', () => {
      this.setState({ isLoading: false });
    });

    Router.events.on('routeChangeError', () => {
      this.setState({ isLoading: false });
    });
  }

  render() {
    const { Component, pageProps } = this.props;
    const { isLoading } = this.state;

    return (
      <Fragment>
        <Head>
          <title>My App</title>
          <meta name="viewport" content="width=device-width, initial-scale=1" />
          <meta charSet="utf-8" />
        </Head>
        {/* You could also pass isLoading state to Component and handle logic there */}
        <Component {...pageProps} />
        {isLoading && 'STRING OR LOADING COMPONENT HERE...'}
      </Fragment>
    );
  }
}

MyApp.getInitialProps = async ({ Component, ctx }) => {
  let pageProps = {};

  if (Component.getInitialProps) {
    pageProps = await Component.getInitialProps(ctx);
  }

  return { pageProps };
};

export default MyApp;
like image 127
Julian Flynn Avatar answered Dec 21 '22 10:12

Julian Flynn


Use the hook below to inspect router's loading status:

import Router from 'next/router'
import { useState, useEffect } from 'react'

const useRouterLoading = () => {
  const [loading, setLoading] = useState(false)
  useEffect(() => {
    const start = () => setLoading(true)
    const end = () => setLoading(false)
    Router.events.on('routeChangeStart', start)
    Router.events.on('routeChangeComplete', end)
    Router.events.on('routeChangeError', end)
    return () => {
      Router.events.off('routeChangeStart', start)
      Router.events.off('routeChangeComplete', end)
      Router.events.off('routeChangeError', end)
    }
  }, [])
  return loading
}
like image 35
duan Avatar answered Dec 21 '22 10:12

duan