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.
Related
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;
I am trying apply a margin-top as a CSS class to my beginner react-project. However, the margin is not applying. Wondering if someone can clarify if something is wrong? I used create-react-app to create and in the package.json file, it says my react-scripts is 4.0.2 so I believe this is supported. Just not sure what I am doing wrong.Every content that is in a div, p-tags , etc are displaying fine. I just can't get the classes to apply.
.Content {
margin-top: 16px;
}
import React from 'react';
import Aux from '../../hoc/Auxillary';
import classes from './Layout.css';
const layout = (props) => (
<Aux>
<div>Toolbar, SideDrawer, Backdrop</div>
<main className={classes.Content}>
{props.children}
</main>
</Aux>
);
export default layout;
Change this:
import classes from './Layout.css';
To
import './Layout.css';
Then change this:
<main className={classes.Content}>
to
<main className={"Content"}>
If you're bent on importing your css file like so:
import classes from './Layout.css';
Change your CSS file name to ./layout.module.css, then import it this way:
import classes from './layout.module.css';
And only then can you access css class names using:
classes.Content
More on file naming conventions here: https://create-react-app.dev/docs/adding-a-css-modules-stylesheet/
I'm trying to add css to my newly created component. When I use inline styles it works. But when I try to import css from another separate file it doesn't work. Below I mention my 2 files.
Layouts.css
.Content {
margin-top: 16px;
}
Layouts.js
import React from 'react';
import Auxillary from './../../hoc/Auxillary'
import classes from './Layouts.css'
const Layout = (props) => (
<Auxillary>
<div>
Toolbar,Sidebar,Backdrop
</div>
<main className={classes.Content}>
{props.children}
</main>
</Auxillary>
);
export default Layout;
Have you tried making className='Content'
If you want to use classes.Content you must name your Layout css file like this
Layouts.module.css
When I route my app to another component by using react-router-dom, the CSS doesn't change.
This is a minimalistic version of the code to demonstrate
App.js
import React from 'react';
import Home from './Home';
function App() {
return (
<div>
<Home></Home>
</div>
);
}
export default App;
Home.js
import React from 'react';
import './Home.css';
const Home = () => {
return (
<h1>Home</h1>
);
}
export default Home;
Home.css
body {
background-color: blue;
}
Dashboard.js
import React from 'react';
import './Dashboard.css';
import React from 'react';
import './Dashboard.css';
const Dashboard = () => {
return (
<div className='content'>
<h1>Dashboard</h1>
</div>
);
}
export default Dashboard;
Dashboard.css
.content {
display: flex;
align-content: center;
align-items: center;
}
index.js
import React from 'react';
import ReactDOM from 'react-dom';
import './index.css';
import App from './App';
import Dashboard from './Dashboard';
import * as serviceWorker from './serviceWorker';
import { BrowserRouter as Router, Route } from 'react-router-dom';
ReactDOM.render(
<Router>
<div>
<Route exact path='/' component={App} />
<Route path='/dashboard' component={Dashboard} />
</div>
</Router>, document.getElementById('root'));
// If you want your app to work offline and load faster, you can change
// unregister() to register() below. Note this comes with some pitfalls.
// Learn more about service workers: ...
serviceWorker.unregister();
When I do /dashboard, it loads the Dashboard component, but it keeps the previous CSS that was loaded from the Home component that resides the App component. The background stays blue. I want that when I route to another component because I changed the URL, it loads whatever CSS that new component has attached to it and gets rid of whatever CSS was before. Is that possible?
Edit: I have made an example in CodeSandbox to illustrate. It's a little different from the code above due to the limitations of the playground, but the functionality is the same.
From what can be seen, importing as a module ends up importing it globally. If we comment the line import Home from "./Home"; the blue background disappears. Just importing the component, imports the whole CSS despite the CSS being imported in a modular way. I'm not sure if I am missing something.
Edit 2:
Here are the different solutions I tried:
CSS Modules, but the body style was still globally loaded.
Styled components don't let me modify the body or html selectors CSS. They require me to create a <div> element and
then have that element span the whole body which I would style
as if it was the body. Which is a workaround I don't want to use because for that I rather use CSS Modules for the whole body spanning .
Inline styling also doesn't let me modify the body or html selectors CSS. I would also need to use a workaround like a body spanning <div> as in Styled components.
The problem
When you import a css like you're doing here
import './Home.css';
you're importing it in a global scope, which means it will not disappear once imported.
The solutions
CSS Modules
What you want is either CSS Modules, which is used like this:
import styles from './Home.css';
<a className={styles.myStyleClass}>Hello</a>
Styled components
or a CSS-in-js framework such as styled components which is used like this:
import styled from 'styled-components';
const MyStyledElement = styled.a`
color: blue;
`;
<MyStyledElement>Hello</MyStyledElement>
Regular objects / inline styling
or just "regular" CSS-in-js like:
const myStyle = {
color: blue;
}
<a style={myStyle}>Hello</a>
There are plenty of options when it comes to styling, these alternatives are popular ones that I encourage you to explore and see which you enjoy.
After doing some more tests I have concluded that as of now it is not possible to change whatever CSS styles have been applied to a <body> or <html> selector in an React SPA when a CSS file is already loaded and one uses React Router to render other components. I still appreciate the answers and the time taken to help me find a solution. They are still valid answers if we are not talking about the <body> or <html> node in an HTML document. From them I learned about other ways to use CSS in React. I modified the original post with the solutions I tried.
What ended working was modifying the DOM styles with JavaScript whithin the component itself.
Home.js
import React from "react";
const Home = () => {
// Modify the DOM Styles with JavaScript
document.body.style.backgroundColor = "blue";
// Or uncomment below to modify the
// document root background color
// which in this case would be <html>
//document.bgColor = "blue";
// Or modify the root tag style of the document instead of the
// <body> (<html> in this case)
//document.documentElement.setAttribute('style', 'background-color: green');
return (
<div>
<h1>Home</h1>
<form action="/dashboard">
<input type="submit" value="Go to Dashboard" />
</form>
</div>
);
};
export default Home;
Here is a working example:
Where my app wasn't loading style sheets and the like. However, I was importing my assets directly into my index.html entry point.
By replacing the links with absolute paths as per this documentation, my problem was resolved.
For me, this meant changing
<head>
<link rel="stylesheet" href="./style.css" ></link>
</head>
to this:
<head>
<link rel="stylesheet" href="/style.css" ></link>
</head>
I'm not sure if the same thing would work for your import statements, but it is worth a shot.
More info: styles-not-working-with-react-router
I'm using facebook's create-react app for my application:
In my Login.js container, I am importing CSS like so:
import React from 'react';
import '../../styles/users/Login.css'
const Login = () => {
....
The problem is the Login.css styles are being applied to my entire application... for example, if Login.css has:
body {
background:Red ;
}
The entire app would have a body of background: Red; Even outside of the Login container.
What I expected/want is for a CSS import within a container to only apply to that particular container.
Is that possible w React? How are react developers supposed to handle container specific stylings? Do I need to add an ID to all containers and include that in the entire CSS file?
1. Solution: Give your DOM elements class names to use them in your css.
JS:
// in Link.js
import React from 'react';
import '../../styles/Link.css'
const Link = ({children, href}) => (
<a className="link" href={href}>{children}</a>
);
CSS:
// Link.css
.link {
color: red;
}
2. Solution: Inline styles.
JS:
// in Link.js
import React from 'react';
import '../../styles/Link.css'
const Link = ({children, href}) => (
<a style={color: 'red'} href={href}>{children}</a>
);
3. Solution: CSS in JS.
There are some libraries that try to solve the styling issue:
Watch this talk: https://speakerdeck.com/vjeux/react-css-in-js
And have a look at this: https://github.com/cssinjs
styled-components: https://github.com/styled-components/styled-components
The best and easiest solution is to give classNames to every element you have in your code. I had the same issue when trying to apply widths and heights to my images and eventually found out that it was affecting whole app.