How to add Styled Components to Next.js project using TypeScript

#react #nextjs #css #typescript

Want to use styled components in your Next.js project? Also using TypeScript?

Here are the steps we need to do:

Add the styled components library with types
Add the special babel plugin
Create _document.tsx and _app.tsx files
Create styled.d.ts declaration file.

Add the styled components library with types

Run

yarn add styled-components
yarn add @types/styled-components

Add the special babel plugin

yarn add --dev babel-plugin-styled-components

Create .babelrc file with the following:

{
  "presets": ["next/babel"],
  "plugins": [["styled-components", { "ssr": true }]]
}

Create `_document.tsx` and `_app.tsx` files

Create in pages/_document.tsx file

import Document from "next/document";
import { ServerStyleSheet } from "styled-components";

export default class MyDocument extends Document {
  static async getInitialProps(ctx) {
    const sheet = new ServerStyleSheet();
    const originalRenderPage = ctx.renderPage;

    try {
      ctx.renderPage = () =>
        originalRenderPage({
          enhanceApp: (App) => (props) =>
            sheet.collectStyles(<App {...props} />),
        });

      const initialProps = await Document.getInitialProps(ctx);
      return {
        ...initialProps,
        styles: (
          <>
            {initialProps.styles}
            {sheet.getStyleElement()}
          </>
        ),
      };
    } finally {
      sheet.seal();
    }
  }
  render() {
    return (
      <Html>
        <Head />
        <body>
          <Main />
          <NextScript />
        </body>
      </Html>
    );
  }
}

Create pages/_app.tsx and paste the following:

import { createGlobalStyle, ThemeProvider } from "styled-components";

const GlobalStyle = createGlobalStyle`
  body {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
  }
  * {
    font-family: 'Open Sans', sans-serif;
  }
`;

const theme = {
  colors: {
    primary: "#0070f3",
  },
};

export default function App({ Component, pageProps }) {
  return (
    <>
      <GlobalStyle />
      <ThemeProvider theme={theme}>
        <Component {...pageProps} />
      </ThemeProvider>
    </>
  );
}

Create `styled.d.ts` declaration file.

Create a declarations file for TypeScript in the project root. Let's name it styled.d.ts

import "styled-components";

declare module "styled-components" {
  export interface DefaultTheme {
    colors: {
      primary: string;
    };
  }
}

So if we want to describe the shape of our Theme, we can do it here.

Use the library

Rename index.js to index.tsx, delete everything and paste the following:

import React from "react";
import styled from "styled-components";

const Title = styled.h1`
  font-size: 50px;
  color: ${({ theme }) => theme.colors.primary};
`;

const Home: React.FC = () => {
  return <Title />;
};

export default Home;