Gatsby Styled-Components Dark Mode

A Gatsby plugin that handles injecting a dark and light theme, as well as functionality for toggling between them. It also persists the state of your users' dark option in their browsers.

Installation

Install the package

$ npm i gatsby-styled-components-dark-mode

or

$ yarn add gatsby-styled-components-dark-mode

Add the plugin to your gatsby-config.js

module.exports = {
  plugins: [
    {
      resolve: `gatsby-styled-components-dark-mode`,
      options: {
          light: { mainColor: 'brandyRose'},
          dark: { mainColor: 'manatee'},
      },
    },
  ],
}

Requirements

You must have the following installed in your gatsby project:

• styled-components
  • Use this plugin for gatsby integration

How to Use

The plugin expects two options in your gatsby-config.js file:

light: object
dark: object

These objects are defined by you in your project, so you have full control over your styling. Everything else is handled for you.

in a presumed src/theme.js

export const darkTheme = {
    mainColor: 'topaz',
    secondaryColor: 'ruby',
}

export const lightTheme = {
    mainColor: 'pampas',
    secondaryColor: 'ruby',
    buttonColor: 'shadyLady',
    // Note both themes don't necessary have to match (you'll probably want them to though)
}

in gatsby-config.js

module.exports = {
  plugins: [
    {
      resolve: `gatsby-styled-components-dark-mode`,
      options: {
        light: require(`${__dirname}/src/theme.js`).lightTheme,
        dark: require(`${__dirname}/src/theme.js`).darkTheme,
      },
    },
  ],
}

Multiple files

You may want to keep your themes separate, thus you could do the following:

in src/darkTheme.js

const darkTheme = {
    mainColor: 'topaz',
    secondaryColor: 'ruby',
}

export default darkTheme;

in src/lightTheme.js

const lightTheme = {
    mainColor: 'pampas',
    buttonColor: 'shadyLady',
}

export default lightTheme

in gatsby-config.js

module.exports = {
  plugins: [
    {
      resolve: `gatsby-styled-components-dark-mode`,
      options: {
        light: require(`${__dirname}/src/lightTheme.js`),
        dark: require(`${__dirname}/src/darkTheme.js`),
      },
    },
  ],
}

Accessing the styles

We can now utilize the power of styled-components. Any component wrapped in a styled or css has access to your theme!

in a component

const MyLightOrDarkStyledComponent = styled.div`
    background-color: ${props => props.theme.mainColor};
    color: ${props => props.theme.secondaryColor};
`

or

const MyThemedUpComponent = withTheme((props) => (
    <div styles={{ color: props.theme.mainColor }}>Hello world</div>
))

// I don't recommend this approach unless you really have/want to

In theme you'll also have access to isDark

So you could do conditionally styling inside your styled components if you wanted to

const MyLightOrDarkStyledComponent = styled.div`
    color: ${props => props.theme.isDark ? props.theme.darkColor : props.theme.lightColor};
`

Toggling the theme

Somewhere in your app, you'll want to provide functionality to actually change the theme from one theme to the other.

The plugin exposes this functionality through ThemeManagerContext

Consuming the context will get you access to

prop	type	description
isDark	boolean	state that describes if your app is in dark mode or not
toggleDark	(value?: boolean) => void	function that toggles dark/light mode

Example

in a presumed src/component/layout.tsx

import { ThemeManagerContext } from "gatsby-styled-components-dark-mode"

export const Layout = (props) => {
  const themeContext = useContext(ThemeManagerContext)

  return (
    <div>
      <label>
        <input
          type="checkbox"
          onChange={() => themeContext.toggleDark()}
          checked={themeContext.isDark}
        />{" "}
        Dark mode
      </label>
    </div>
  )
}

And that's really all there is to it

Notice you'll also get isDark, so you can conditionally render components like so:

import { ThemeManagerContext } from "gatsby-styled-components-dark-mode"

export const Layout = (props) => {
  const themeContext = useContext(ThemeManagerContext)

  return (
    <div>
        {themeContext.isDark ? <div>dark component</div> : <div>other component</div>}
    </div>
  )
}

Global Styling

Until further notice, global styling requires a tad bit more overhead due to what styled-components' api offers.

Keep in mind, this is not required.

Your theme already knows if it's dark/light so all you have to do is pass the theme object to a createGlobalStyle function

Check the docs for more info

Usage

in a presumed src/theme.js

export const GlobalStyle = createGlobalStyle`
  html, body {
    height: 100%; 
  }
  
  body {
    background-color: rgb(${props => props.theme.global.bg});
    color: rgb(${props => props.theme.global.color});
  }
  
  a {
    color: rgb(${props => props.theme.global.link});
  }
  
  a:hover {
    color: rgb(${props => props.theme.global.linkHover});
  }
  
  blockquote {
    color: inherit;
    border-left-color: inherit;
  }
`

You'll probably want to render this in your root - layout.jsx is a good place to start

in src/layout.jsx

import { GlobalStyle } from "./theme"

export const Layout = withTheme((props) => {
  return (
    <div>
        <GlobalStyle theme={props.theme} /> 
        // content
    </div>
  )
})

Notice we use withTheme to grab the theme object itself and pass it to the global stylesheet

Full Example

gatsby-config.js

module.exports = {
  plugins: [
    {
      resolve: `gatsby-styled-components-dark-mode`,
      options: {
        light: require(`${__dirname}/src/theme.js`).lightTheme,
        dark: require(`${__dirname}/src/theme.js`).darkTheme,
      },
    },
  ],
}

src/theme.js

import { createGlobalStyle } from "styled-components"

// I'm using rgb numbers here for easily using rgba styling throughout the app
// You can put hexcodes, names, or any other definitions that fits the context of your app
const colorPalette = {
  lightShades: "242, 242, 241",
  lightAccent: "139, 142, 149",
  mainBrand: "140, 100, 88",
  darkAccent: "133, 129, 137",
  darkShades: "32, 30, 32",

  success: "95, 153, 81",
  warning: "221, 136, 25",
  error: "244, 67, 54",
}

const baseTheme = {
  actions: {
    error: colorPalette.error,
    info: colorPalette.darkShades,
    primary: colorPalette.mainBrand,
    success: colorPalette.success,
    warning: colorPalette.warning,
  },
  palette: {
    darkAccent: colorPalette.darkAccent,
    darkShades: colorPalette.darkShades,
    lightAccent: colorPalette.lightAccent,
    lightShades: colorPalette.lightShades,
    mainBrand: colorPalette.mainBrand,
  },
}

export const darkTheme = {
  ...baseTheme,
  global: {
    bg: colorPalette.darkShades,
    color: colorPalette.lightShades,
    link: colorPalette.mainBrand,
    linkHover: colorPalette.lightAccent,
  },
}

export const lightTheme = {
  ...baseTheme,
  global: {
    bg: colorPalette.lightShades,
    color: colorPalette.darkShades,
    link: colorPalette.mainBrand,
    linkHover: colorPalette.darkAccent,
  },
}

export const GlobalStyle = createGlobalStyle`
  html, body {
    height: 100%; 
  }
  body {
    background-color: rgb(${props => props.theme.global.bg});
    color: rgb(${props => props.theme.global.color});
    
    transition: background 0.2s ease-out;
  }
  
  a {
    color: rgb(${props => props.theme.global.link});
  }
  
  a:hover {
    color: rgb(${props => props.theme.global.linkHover});
  }
`

src/layout.js

import { ThemeManagerContext } from "gatsby-styled-components-dark-mode"
import React, { useContext } from "react"
import styled, { withTheme } from "styled-components"
import { GlobalStyle } from "./theme"

const MainHeading = styled.h2`
  color: rgb(${props => props.theme.palette.mainBrand});
`

export const Layout = withTheme((props) => {
  const { children, theme } = props
  
  const themeContext = useContext(ThemeManagerContext)

  return (
    <div>
      <GlobalStyle theme={theme} />
      <header>
        <MainHeading>
          <a href={'#'}>Gatsby Dark Theme</a>
        </MainHeading>
        <div>
          <label>
            <input
              type="checkbox"
              onChange={() => themeContext.toggleDark()}
              checked={themeContext.isDark}
            />{" "}
            Dark mode
          </label>
        </div>
      </header>
      <main>{children}</main>
    </div>
  )
})

Set Dark Mode as default

In case you want to set the dark mode as your default theme, follow the following example.

src/layout.js

import { ThemeManagerContext } from "gatsby-styled-components-dark-mode"
import React, { useContext, useEffect } from "react"
import styled, { withTheme } from "styled-components"

export const Layout = withTheme((props) => {
  const themeContext = useContext(ThemeManagerContext)

  // Add this line
  useEffect(() => themeContext.toggleDark(true), [])

  return (
    ...
  )
})

Typescript Example

https://github.com/gperl27/website

Roadmap

• typescript

• hot-reload

Currently, when changing a theme, the app will recompile but will not hot reload. You have to do a full page-refresh to see your theming changes.

• improved global styling

Ideally, I would like to pass { global: "path/to/globalStyles } where these styles can get interpolated/compiled into something that's friendly enough for styled-components' createGlobalStyle api.

• live demo

• default theme setup or scaffolding if people want it