theme-change

v2.5.0

Published

a year ago

Change CSS theme with toggle, buttons or select using CSS Variables and localStorage

Downloads

34,735

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saadeghi

javascript theming theme css

🎨 CSS Theme Change

A tiny JS script to handle CSS themes
Change CSS theme using button, toggle or a <select>
It saves chosen theme in browser and uses it again when page reloads

🖥 Demo

See example code on codepen
See Sample site on Netlify
See Vue Example on Vercel

💿 Use

JS

Use CDN:

<script src="https://cdn.jsdelivr.net/npm/[email protected]/index.js"></script>

Install: npm i theme-change --save and use it in your js file:

import { themeChange } from 'theme-change'
themeChange()

Install: npm i theme-change --save and use it in your js file:

import { useEffect } from 'react'
import { themeChange } from 'theme-change'

useEffect(() => {
  themeChange(false)
  // 👆 false parameter is required for react project
}, [])

Install: npm i theme-change --save and use it in your js file:

import { onMounted } from 'vue'
import { themeChange } from 'theme-change'

export default {
  setup() {
    onMounted(() => {
      themeChange(false)
    })
  },
}

Install: npm i theme-change --save and use it in your js file:

import { themeChange } from 'theme-change'

export default {
  mounted: function () {
    themeChange(false)
  },
}

Install: npm i theme-change --save and use it in your svelte component that uses one theme-change attributes:

import { onMount } from 'svelte'
import { themeChange } from 'theme-change'

// NOTE: the element that is using one of the theme attributes must be in the DOM on mount
onMount(() => {
  themeChange(false)
  // 👆 false parameter is required for svelte
})

Install: npm i theme-change --save and use it in your js/jsx/tsx file:

import { onMount } from 'solid-js'
import { themeChange } from 'theme-change'
onMount(async () => {
  themeChange();
})

Install: npm i theme-change --save and use it in your .astro file(s):

Astro is a bit tricky because of how is rendering html page as a MPA (Multiple Pages Application) Astro projects are therefore subject to FART problem. To prevent this we will use the is:inline astro directive.

If you want to apply themes on a single astro page (remember Astro is an MPA framework) :

src/pages/mypage.astro

---
---

<html lang="en">
  <head>
  <script is:inline>
      // ☝️ This script prevent the FART effect.
      if (localStorage.getItem("theme") === null) {
        document.documentElement.setAttribute("data-theme", "light");
      } else
      document.documentElement.setAttribute("data-theme",localStorage.getItem("theme"));
      // "theme" LocalStorage value is set by the package to remember user preference.
      // The value is checked and applyed before rendering anything.
  </script>
  <script>
      import { themeChange } from "theme-change";
      themeChange();
       // 👆 you could import the CDN directly instead of these two lines
    </script>
    <title>My crazy credit page</title>
  </head>
  <body>
    <h1>Welcome to my credit page!</h1>
  </body>
</html>

If you want to apply themes to all your astro pages, you need to execute both scripts in a Astro layout, it would need to wrap all your astro pages like so:

src/layouts/MyCrazyLayout.astro

---
---

<html lang="en">
  <head>
    <script is:inline>
      // ☝️ This script prevent the FART effect.
      if (localStorage.getItem("theme") === null) {
        document.documentElement.setAttribute("data-theme", "light");
      } else
        document.documentElement.setAttribute(
          "data-theme",
          localStorage.getItem("theme")
        );
      // "theme" LocalStorage value is set by the package to remember user preference.
      // The value is checked and applyed before rendering anything.
    </script>
    <script>
      import { themeChange } from 'theme-change';
      themeChange();
      // 👆 you could import the CDN directly instead of these two lines
    </script>
    <meta charset="utf-8" />
    <title>My Cool Astro Layout Wraping All My Pages</title>
    <meta name="viewport" content="width=device-width, initial-scale=1" />
  </head>
  <body>
    <nav>
      <a href="#">Home</a>
      <a href="#">Posts</a>
      <a href="#">Contact</a>
    </nav>
    <article>
      <slot />
      <!-- your content from src/pages/index.astro is injected here -->
    </article>
  </body>
</html>

src/pages/index.astro

---
import MyCrazyLayout from '../layouts/MyCrazyLayout.astro';
---
<MySiteLayout>
  <p>My page content, wrapped in a layout!</p>
</MySiteLayout>

CSS

Set your themeable style as custom properties in CSS like this:

:root {
  --my-color: #fff;
  /* or any other variables/style */
}
[data-theme='dark'] {
  --my-color: #000;
}
[data-theme='pink'] {
  --my-color: #ffabc8;
}

then use your variables on any element

body {
  background-color: var(--my-color);
}

HTML

There are 3 options:

Using buttons to set a theme

Clicking on these buttons, sets the chosen theme and also adds the ACTIVECLASS to the chosen button

<button data-set-theme="" data-act-class="ACTIVECLASS"></button>
<button data-set-theme="dark" data-act-class="ACTIVECLASS"></button>
<button data-set-theme="pink" data-act-class="ACTIVECLASS"></button>

Toggle between two themes
Clicking on this element, toggles between dark and light theme and also adds the ACTIVECLASS to the element
```
<button data-toggle-theme="dark,light" data-act-class="ACTIVECLASS"></button>
```

`<select>` menu

<select data-choose-theme>
  <option value="">Default</option>
  <option value="dark">Dark</option>
  <option value="pink">Pink</option>
</select>

Advance use

@media (prefers-color-scheme: dark){
  :root{
    --my-color: #252b30;
  }
}

If you're using Purge CSS, you might need to safe list your CSS using the comments below because your secondary themes will be purged

Safelist [data-theme] on postcss config

module.exports = {
  purge: {
    options: {
      safelist: [/data-theme$/],
    },
  },
}

Safelist inside CSS file

/*! purgecss start ignore */

[data-theme='dark'] {
  --my-color: #252b30;
}

/*! purgecss end ignore */

If you want to use a custom localStorage key, you can add it to the data-key attribute like this:

<select data-choose-theme data-key="admin-panel">

<button data-key="front-page" data-set-theme="">

<span data-key="premium-user-theme" data-toggle-theme="dark">

Published

Vulnerabilities

Links

Maintainers

Keywords

Readme

🎨 CSS Theme Change

🖥 Demo

💿 Use

JS

CSS

HTML

Using buttons to set a theme

Toggle between two themes

<select> menu

Advance use

`<select>` menu