theme-selector

A Web Component for setting a website theme using a select element.

Demo | Further reading

Examples

General usage example:

<script type="module" src="theme-selector.js"></script>

<theme-selector>
    <select autocomplete="off">
        <option value="light">
            Light
        </option>
        <option value="dark">
            Dark
        </option>
    </select>
</theme-selector>

<style>
    theme-selector:not(:defined) {
        display: none;
    }
</style>

Example using a custom storage key:

<script type="module" src="theme-selector.js"></script>

<theme-selector data-key="color-scheme">
    <select autocomplete="off">
        <option value="light">
            Light
        </option>
        <option value="dark">
            Dark
        </option>
    </select>
</theme-selector>

<style>
    theme-selector:not(:defined) {
        display: none;
    }
</style>

Example using a custom dark theme key:

<script type="module" src="theme-selector.js"></script>

<theme-selector data-dark-theme="white-on-black">
    <select autocomplete="off">
        <option value="black-on-white">
            Black on White
        </option>
        <option value="white-on-black">
            White on Black
        </option>
    </select>
</theme-selector>

<style>
    theme-selector:not(:defined) {
        display: none;
    }
</style>

Example with a custom transition class and duration to keep the class applied:

<script type="module" src="theme-selector.js"></script>

<theme-selector data-transition-class="transitioning" data-transition-duration="100">
    <select autocomplete="off">
        <option value="light">
            Light
        </option>
        <option value="dark">
            Dark
        </option>
    </select>
</theme-selector>

<style>
    theme-selector:not(:defined) {
        display: none;
    }
</style>

Example targeting a specific element to apply the theme to:

<script type="module" src="theme-selector.js"></script>

<theme-selector data-root-element=".content">
    <select autocomplete="off">
        <option value="light">
            Light
        </option>
        <option value="dark">
            Dark
        </option>
    </select>
</theme-selector>

<style>
    theme-selector:not(:defined) {
        display: none;
    }
</style>

Features

This Web Component allows you to use a select element to control user-preferred theming across your website by setting a data attribute against the root element (or a defined selector query). Additionally saves the preference to local storage so that it can be applied on new page loads and maintained between user visits.

Installation

You have a few options (choose one of these):

1. Install via npm: npm install @chrisburnell/theme-selector
2. Download the source manually from GitHub into your project.
3. Skip this step and use the script directly via a 3rd party CDN (not recommended for production use)

Usage

Make sure you include the <script> in your project (choose one of these):

<!-- Host yourself -->
<script type="module" src="theme-selector.js"></script>

<!-- 3rd party CDN, not recommended for production use -->
<script
  type="module"
  src="https://www.unpkg.com/@chrisburnell/[email protected]/theme-selector.js"
></script>

<!-- 3rd party CDN, not recommended for production use -->
<script
  type="module"
  src="https://esm.sh/@chrisburnell/[email protected]"
></script>

Credit

With thanks to the following people:

• David Darnes for creating this Web Component repo template
• Andy Bell for writing the article, Create a user controlled dark or light mode, which served as the initial inspiration and basis for building my own theming setup and eventually became this Web Component