nextjs " Failed to compile pages/_app.js " how to fix it [duplicate] - next.js

This question already has answers here:
Next.js Global CSS cannot be imported from files other than your Custom <App>
(11 answers)
Closed 1 year ago.
How to fix it, it happens when compiling

This is the official document for your problem from the Next.js team:
https://nextjs.org/docs/basic-features/built-in-css-support
You need to import global CSS in the _app.js file to use it globally in your application.
For example, use Tailwind CSS as global like this:
// your _app.js file
// import your CSS file you want to use globally here
import 'tailwindcss/tailwind.css';
const CustomApp = ({ Component, pageProps }) => (
<Component {...pageProps} />
);
export default CustomApp;
If you just want to use CSS for specific components, please use module CSS. It will be helpful to code splitting your bundle files when you build the production version.
Example to use modular CSS just only for your component:
import styles from './index.module.scss';
const YourComponent = () => {
return <div className={styles.example}>...</div>;
};
export default YourComponent;
For special cases that you need to import CSS files from the library inside your node_modules. You can import that CSS file from node_modules inside your specific component.
For example:
import { FC } from 'react';
import Slider from 'react-slick';
import 'react-slick/css/slick.css';
import 'react-slick/css/slick-theme.css';
const SlickSlider: FC<any> = ({ children, ...restProps }) => {
return <Slider {...restProps}>{children}</Slider>;
};
export default SlickSlider;

Related

CSS file is applying on another react component even without importing

Hello I'm using React to build a website and I want to use .CSS files for my CSS and I'm using import './example.css' in my component file.
Example:
import React from 'react';
import 'Home.css';
const Home = () => {
return (
<div className="example">
Hi
</div>
)
}
and if i create another page but don't import this CSS file, I get the styles on my other page
other page:
import React from 'react';
const About= () => {
return (
<div className="example">
Hi
</div>
)
}
Any reason and solution for this?
When importing a css file like you've done it will be injected into the project and not just into the component you're importing it from.
What you're looking for is css-modules (adding css-modules using create-react-app)
import React from 'react';
import styles from 'Home.css';
const Home = () => {
return (
<div className={styles.example}>
Hi
</div>
)
}
The reason is that you are using the same class in both of your components.
Doing import 'Home.css' does not encapsulate .css only for that component, all of the .css gets bundled together so it ends up overwriting styles somewhere down the line.
For each of the components, you can specify a unique className on top of your component, and use that class to style only that component.
.home-container .header { ... }
You can also make one global .css part to put styles that you want to keep using throughout the whole app.

How can I create a ThemeProvider that adds a global css file?

How would you add a global css file as a custom ThemeProvider component in React? I'm building a component library for NPM. So it would enable another React application to use the css file globally.
I've tried creating one like this:
import React from 'react';
import './global.css';
interface Types {
children: React.ReactNode
}
export default (props:Types) => <div>{props.children}</div>
I found a neat solution. It creates a <style /> tag with the contents of a css file:
import React from 'react';
import styles from './global.css'
interface Types {
children: React.ReactNode
}
export default (props:Types) => (
<>
<style dangerouslySetInnerHTML={{__html: styles.replace(' ', '')}} />
<div>{props.children}</div>
</>
)

Next.js Global CSS cannot be imported from files other than your Custom <App>

My React App was working fine, using global CSS also.
I ran npm i next-images, added an image, edited the next.config.js, ran npm run dev, and now I'm getting this message
Global CSS cannot be imported from files other than your Custom <App>. Please move all global CSS imports to pages/_app.js.
Read more: https://err.sh/next.js/css-global
I've checked the docs, but I find the instructions a little confusing as I am new to React.
Also, why would this error happen now? Do you think it has anything to do with the npm install?
I've tried to remove new files I've added along with their code, but this doesn't fix the problem. I've also tried what the Read more: suggests.
My highest tier component.
import Navbar from './Navbar';
import Head from 'next/head';
import '../global-styles/main.scss';
const Layout = (props) => (
<div>
<Head>
<title>Bitcoin Watcher</title>
</Head>
<Navbar />
<div className="marginsContainer">
{props.children}
</div>
</div>
);
export default Layout;
My next.config.js
// next.config.js
const withSass = require('#zeit/next-sass')
module.exports = withSass({
cssModules: true
})
My main.scss file
#import './fonts.scss';
#import './variables.scss';
#import './global.scss';
my global.scss
body {
margin: 0;
}
:global {
.marginsContainer {
width: 90%;
margin: auto;
}
}
The thing I find the weirdest is that this error came without changing anything to do with CSS, or Layout.js, and it was previously working?
I've moved my main.scss import to the pages/_app.js page, but the styles still aren't coming through. This is what the _app.js page looks like
import '../global-styles/main.scss'
export default function MyApp({ Component, props }) {
return <Component {...props} />
}
Use the built-in Next.js CSS loader (see here)
instead of legacy #zeit/next-sass.
Replace #zeit/next-sass package with sass.
Remove next.config.js. Or do not change CSS loading in it.
Move the global CSS as suggested in the error message.
Since Next.js 9.2 global CSS must be imported in Custom <App> component.
// pages/_app.js
import '../global-styles/main.scss'
export default function MyApp({ Component, pageProps }) {
return <Component {...pageProps} />
}
To add styles only to a specific component or page you can use built-in support of CSS modules. (see here)
For example, if you have a component Button.js you can create a Sass file button.module.scss and include it in the component.
Next.js stops complaining when your file has module in naming, e.g., changing import '../global-styles/main.scss'; to import '../global-styles/main.module.scss'; would fix the warning and you could have your styles in the global-styles, or for example, in your component.
No extra dependencies/configurations in next.config.js is required.
You can replace the opinionated (and overly-complex?) NextJs CSS loaders with your own. Here's a simple one for global css:
const MiniCssExtractPlugin = require('mini-css-extract-plugin')
module.exports = {
reactStrictMode: true,
webpack: (config, { buildId, dev, isServer, defaultLoaders, webpack }) => {
// Find and remove NextJS css rules.
const cssRulesIdx = config.module.rules.findIndex(r => r.oneOf)
if (cssRulesIdx === -1) {
throw new Error('Could not find NextJS CSS rule to overwrite.')
}
config.module.rules.splice(cssRulesIdx, 1)
// Add a simpler rule for global css anywhere.
config.plugins.push(
new MiniCssExtractPlugin({
experimentalUseImportModule: true,
filename: 'static/css/[contenthash].css',
chunkFilename: 'static/css/[contenthash].css',
})
)
config.module.rules.push({
test: /\.css$/i,
use: !isServer ? ['style-loader', 'css-loader'] : [MiniCssExtractPlugin.loader, 'css-loader'],
})
return config
},
}
Add this to your _app.js
import '../styles/globals.css'
For me the problem was because I had used two module.exports in my next.config.js file like this
const withPlugins = require('next-compose-plugins')
const sass = require('#zeit/next-sass')
const css = require('#zeit/next-css')
const nextConfig = {
webpack: function(config){
config.module.rules.push({
test: /\.(eot|woff|woff2|ttf|svg|png|jpg|gif)$/,
use: {
loader: 'url-loader',
options: {
limit: 100000,
name: '[name].[ext]'
}}
})
return config
}
}
module.exports = withPlugins([
[css],
[sass, {
cssModules: true
}]
], nextConfig)
module.exports = {
env: {
MONGO_URI = 'your uri'
}
}
. 1I modified it to change the export module like this.
const nextConfig = {
webpack: function(config){
config.module.rules.push({
test: /\.(eot|woff|woff2|ttf|svg|png|jpg|gif)$/,
use: {
loader: 'url-loader',
options: {
limit: 100000,
name: '[name].[ext]'
}}
})
return config
},
env: {
MONGO_URI: "your uri"
}
}
2then I deleted the second module.exports
This node package provides a perfect solution for it. You can find it here
Steps to fix it:
1. Add package:
npm install next-remove-imports
or
yarn add next-remove-imports
2. Add this wrapper variable inside your next.config.js
const removeImports = require('next-remove-imports')({
test: /node_modules([\s\S]*?)\.(tsx|ts|js|mjs|jsx)$/,
matchImports: "\\.(less|css|scss|sass|styl)$"
});
All it is doing is re-enabling global styling import rule for tsx|ts|js|mjs|jsx files
3. Wrap your next config export with this next-remove-imports wrapper. Something like this:
module.exports = removeImports((nextConfig)
4. Now restart your react app and you will be able to import CSS files inside any ts|js|js|jsx|mjs file or component.
Try to include ".module" in your scss file name.
Change main.scss to main.module.scss
Example:
import styles from './todolist-profile-info.module.scss'
You did not need to do anything inside of next.config.js.
Let's assume you are using a global css like Bootstrap, meaning it contains css that is meant to be applied to your entire application and all the different pages inside of it.
Global css files have to be wired up to NextJS in a very particular fashion.
So inside of the pages/ directory you need to create _app.js.
It's critical that the file be named _app.js.
Then at the top of that file you would import Bootstrap css in the following manner:
import 'bootstrap/dist/css/bootstrap.css';
Then you would add the following:
export default ({ Component, pageProps }) => {
return <Component {...pageProps} />;
};
So what is going on in that code?
Well, behind the scenes, whenever you try to navigate to some distinct page with NextJS, NextJS will import your component from one of the different files inside your pages/ directory.
NextJS does not just take your component and show it on the screen.
Instead it wraps it up inside of its own custom default component and that is referred to inside of NextJS as the App.
What you are doing by defining the _app.js is to define your own custom app component.
So whenever you try to visit a route inside a browser or your root route, NextJS is going to import that given component and pass it into the AppComponent as the Component prop.
So Component there is equal to whatever components you have in the pages/ directory. And then pageProps is going to be the set of components that you are intending to pass to your files inside of pages/.
So long story short, this thing is like thin wrapper around the component that you are trying to show on the screen.
Why do you have to define this at all?
Well, if you ever want to include some global css to the project, Bootstrap being a global css for example, you can only import global css into the _app.js file.
It turns out that if you try to visit other components or other pages, NextJS does not load up or even parse those files.
So any css you may have imported inside there will not be included in the final HTML file.
So you have a global css that must be included on every single page, it has to be imported into the app file because it's the only file that is guaranteed to be loaded up every single time a user goes to your application.
Don't forget that in addition to importing the css inside of _app.js, you also have to run an npm install bootstrap in your terminal.
You can read more on this here:
https://nextjs.org/docs/messages/css-global
For me, i got this error because I had used improper naming for my project's parent folder, had used special characters in it,
like project#1,
after removing special chars, and changing the folder name to like project-1, the error got away.
In my case there was typo in navbar.module.css
I've written navbar.moduile.css
you must for every component css/scss write navbar.module.css/scss/sass.Next js doesnt compile navbar.css/scss/sass. If hope my answer helps you !.

Dynamically load .css based on condition in reactJS application

I have a reactJS application that I want to make available to multiple clients. Each clients has unique color schemes. I need to be able to import the .css file that corresponds to the specific client.
For example, if client 1 logs into the application, I want to import client1.css. if client 2 logs into the application, I want to import client2.css. I will know the client number once I have validated the login information.
The application contains multiple .js files. Every .js file contains the following at the top of the file
import React from 'react';
import { Redirect } from 'react-router-dom';
import {mqRequest} from '../functions/commonFunctions.js';
import '../styles/app.css';
Is there a way to import .css files dynamically for this scenario as opposed to specifying the .css file in the above import statement?
Thank you
Easy - i've delt with similar before.
componentWillMount() {
if(this.props.css1 === true) {
require('style1.css');
} else {
require('style2.css');
}
}
Consider using a cssInJs solution. Popular libraries are: emotion and styled-components but there are others as well.
I generally recommend a cssInJs solution, but for what you are trying to do it is especially useful.
In Emotion for example they have a tool specifically build for this purpose - the contextTheme.
What cssInJs basically means is that instead of using different static css files, use all the power of Javascript, to generate the needed css rules from your javascript code.
A bit late to the party, I want to expand on #Harmenx answer.
require works in development environments only, once it goes to production you're likely to get errors or not see the css file at all. Here are some options if you, or others, encounter this:
Option 1: Using css modules, assign a variable of styles with the response from the import based on the condition.
let styles;
if(this.props.css1 === true) {
//require('style1.css');
import("./style1.module.css").then((res) => { styles = res;});
} else {
//require('style2.css');
import("./style2.module.css").then((res) => { styles = res;});
}
...
<div className={styles.divClass}>...</div>
...
Option 2: using Suspend and lazy load from react
// STEP 1: create components for each stylesheet
// styles1.js
import React from "react";
import "./styles1.css";
export const Style1Variables = (React.FC = () => <></>);
export default Style1Variables ;
// styles2.js
import React from "react";
import "./styles2.css";
export const Style2Variables = (React.FC = () => <></>);
export default Style2Variables ;
// STEP 2: setup your conditional rendering component
import React, {lazy, Suspense} from "react";
const Styles1= lazy(() => import("./styles1"));
const Styles2= lazy(() => import("./styles2"));
export const ThemeSelector = ({ children }) => {
return (
<>
<Suspense fallback={null} />}>
{isClient1() ? <Styles1 /> : <Styles2/>}
</Suspense>
{children}
</>
);
};
// STEP 3: Wrap your app
ReactDOM.render(
<ThemeSelector>
<App />
</ThemeSelector>,
document.getElementById('root')
);
Option 3: Use React Helm which will include a link to the stylesheet in the header based on a conditional
class App extends Component {
render() {
<>
<Helmet>
<link
type="text/css"
rel="stylesheet"
href={isClient1() ? "./styles1.css" : "./styles2.css"}
/>
</Helmet>
...
</>
}
}
Personally, I like option 2 because you can set a variable whichClientIsThis() then modify the code to:
import React, {lazy, Suspense} from "react";
let clientID = whichClientIsThis();
const Styles= lazy(() => import("./`${clientID}`.css")); // change your variable filenames to match the client id.
export const ThemeSelector = ({ children }) => {
return (
<>
<Suspense fallback={null} />}>
<Styles />
</Suspense>
{children}
</>
);
};
ReactDOM.render(
<ThemeSelector>
<App />
</ThemeSelector>,
document.getElementById('root')
);
This way you don't need any conditionals. I'd still recommend lazy loading and suspending so the app has time to get the id and make the "decision" on which stylesheet to bring in.

How to use AtlasKit Editor with Next.js?

I'm trying to use AtlasKit with Next.js 8, but for some reason, there is a SyntaxError: Unexpected token export error when attempting to build.
I think it's an issue with #atlaskit/editor-core not being properly preprocessed for ES6 (via webpack or babel, etc), but I'm not sure. Any ideas?
//Home.tsx
import * as React from 'react';
import * as classnames from 'classnames';
import * as css from './Home.css';
import { Editor } from '#atlaskit/editor-core';
export const Home: React.FunctionComponent = props => (
<div className={classnames('test', css.home)}>
<Editor />
</div>
);
I've created a repo to replicate the issue here: https://github.com/brandontle/nextjs-with-atlaskit
The file that uses AtlasKit Editor is ~/src/components/Home.tsx.

Resources