I'm using styled-components with next.js so my styles need to be server-side rendered, hence how can I add google analytics to my website?
I checked next.js google analytics example but as I said my _document file is different because of using styled-components.
// _document.js
import React from 'react'
import Document from 'next/document'
import { ServerStyleSheet } from 'styled-components'
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()
}
}
}
export default MyDocument
To correctly initialize gtag, do the following in _document.js or wherever you defined Head:
import { Head } from 'next/document';
export default class MyDocument extends Document {
render() {
return (
// ...
<Head>
<script
async
src="https://www.googletagmanager.com/gtag/js?id=[Tracking ID]"
/>
<script
dangerouslySetInnerHTML={{
__html: `
window.dataLayer = window.dataLayer || [];
function gtag(){dataLayer.push(arguments);}
gtag('js', new Date());
gtag('config', '[Tracking ID]', { page_path: window.location.pathname });
`,
}}
/>
</Head>
);
}
}
The above will track page views on page load. To track navigation add the following to _app.js:
import { useRouter } from 'next/router';
import { useEffect } from "react";
export default const App = () => {
const router = useRouter();
const handleRouteChange = (url) => {
window.gtag('config', '[Tracking ID]', {
page_path: url,
});
};
useEffect(() => {
router.events.on('routeChangeComplete', handleRouteChange);
return () => {
router.events.off('routeChangeComplete', handleRouteChange);
};
}, [router.events]);
return (
// ...
);
};
See also:
In your _document.js you override the getInitialProps method. You can also override the render method. Simply add
render() {
return (
<Html lang={this.props.lang || "en"}>
<Head>
<script
dangerouslySetInnerHTML={{
__html: `[google analytics tracking code here]`
}}
/>
</Head>
<body>
<Main />
<NextScript />
</body>
</Html>
);
}
Make sure you import the required components:
import Document, { Html, Head, Main, NextScript } from "next/document"