/dripsy

🍷 A responsive, theme-based design system for Expo + React Native Web.

Primary LanguageTypeScriptMIT LicenseMIT

🍷 Dripsy

A dead-simple, responsive design system for Expo / React Native Web. Heavily inspired by React's theme-ui.

Style once, run anywhere.

<Text
  sx={{
    fontSize: [14, 16, 20], // 14 on mobile, 16 on tablet, 20 on desktop
    color: ['primary', null, 'accent'], // `primary` on mobile & tablet, `accent` on desktop
  }}
>
  Responsive font size?? 🤯
</Text>

Features

  • (New in 1.4.x!) Custom fonts, edited globally
  • Responsive styles
  • Universal (Android, iOS, Web, & more)
  • Works with Expo
  • Works with Vanilla React Native
  • Works with Next.js / server-side rendering
  • Full theme support
  • Custom theme variants
  • TypeScript support (TypeScript theme support is in the works too)
  • Insanely simple API (themed, responsive designs in one line!)
  • Works with Animated/Reanimated values
  • Dark mode / custom color modes

Examples

More examples coming soon!

  • Create a browser mockup with Dripsy: Snack

🤔 Why?

Build once, deploy everywhere, is a great philosophy made possible by Expo Web/React Native Web. A large impediment is responsive design.

React Native doesn't have media queries for styles, and trying to micmick it with JS turns into useState hell with a ton of conditionals (as you'll see below.)

While React Native has some great component libraries, it lacks a good design system that is responsive and themed.

No longer. The goal of Dripsy is to let you go from idea to universal, themed styles without much effort.

There is no shortage of discussion about what responsive design should look like in React Native.

After trying many, many different ways, I'm convinced this approach is the answer. I'm curious to see if you'll think the same.

🙉 Installation

yarn add dripsy

# or
npm i dripsy

If you're using Next.js or another SSR app, scroll down to see how to configure.

🛠 Set up

Technically, you don't have to do anything else!

However, you'll likely want to create a custom theme.

Custom theme

Wrap your entire app with the DripsyProvider, and pass it a theme object. Make sure you create your theme outside of the component to avoid re-renders.

If you're using Next.js, this goes in pages/_app.js.

App.js

import { DripsyProvider } from 'dripsy'

const theme = {
  colors: {
    text: '#000',
    background: '#fff',
    primary: 'tomato',
  },
  fonts: {
    root: 'circular',
  },
  // custom fonts are easy!
  customFonts: {
    circular: {
      default: 'Circular-StdBook',
      bold: 'Circular-StdBold',
      black: 'Circular-StdBlack'
    }
  },
  space: [10, 12, 14],
  text: {
    thick: {
      fontFamily: 'root',
      fontWeight: 'black' // 'Circular-StdBlack'
    }
  }
}

export default function App() {
  return (
    <DripsyProvider theme={theme}>
      {/* Your app code goes here! */}
    </DripsyProvider>
  )
}

Follow the docs from theme-ui to see how to theme your app – we use the same API as them.

My personal preference is to have the entire theme object in one file.

All theme values are optional. You don't have to use them if you don't want.

For SSR apps (Next.js, Gatsby, etc.)

If you are not using Next.js, skip down to #3 below.

Steps 1 & 2 are required for Next.js apps (for example, if you're using Expo + Next.js.)

1. Install dependencies

yarn add next-compose-plugins next-transpile-modules

2. Edit your next.config.js file to look like this:

const withPlugins = require('next-compose-plugins')
const withTM = require('next-transpile-modules')([
  'dripsy',
  // you can add other packages here that need transpiling
])

const { withExpo } = require('@expo/next-adapter')

module.exports = withPlugins(
  [withTM],
  withExpo({
    projectRoot: __dirname,
  })
)
  1. Add SSRStyleReset to the top of your body

Import SSRStyleReset and inject it at the top of your body HTML tag.

import { SSRStyleReset } from 'dripsy'
;<body>
  <SSRStyleReset />
  <YourApp />
</body>

If you're using Next.js, this should go in pages/_document.js.

Your pages/_document.js should look something like this.

We'll add other library examples here too, such as Gatsby.


That's it! Btw, if you're using Expo + Next.js, check out my library, expo-next-react-navigation to help with navigation.

👀 What does Dripsy look like

Create a theme

export default {
  colors: {
    text: '#000',
    background: '#fff',
    primary: 'tomato',
  },
  spacing: [10, 12, 14],
  fontSizes: [16, 20, 24],
  text: {
    h1: {
      fontSize: 3, // this is 24px, taken from `fontSize` above
    },
    p: {
      fontSize: 1, // & this is 16px, taken from `fontSize` above
    },
  },
}

...and build a beautiful, responsive UI

<Text
  sx={{
    color: 'primary',
    padding: [1, 3], // [10px, 14px] from theme!
  }}
>
  Themed color!
</Text>

...you can even use "HTML" elements

import { H1, H2, P } from 'dripsy'
;<H1
  sx={{
    color: 'text', // #000 from theme!
    fontSize: 2, // 24px from theme!
  }}
></H1>

Credit to Evan Bacon for @expo/html-elements, used above!


Todo: make the theme values show up in TS types for intelliesense.

Usage

Dripsy is an almost-drop-in replacement for React Native's UI components.

Change your imports from react-native to dripsy

- import { View, Text } from 'react-native'
+ import { View, H1, P } from 'dripsy'

Use the sx prop instead of style to use themed and responsive styles:

<View
  sx={{
    height: [100, 400],
    backgroundColor: 'primary',
    marginX: 10,
  }}
/>

Also, instead of marginHorizontal, use marginX or mx, as seen on the theme-ui docs.

Animated Values

To use an animated view, simple use the as prop.

import { View } from 'dripsy'
import Animated from 'react-native-reanimated'
import { useValue } from 'react-native-redash'

function App() {
  const height = useValue(0)

  return <View as={Animated.View} sx={{ height }} />
}

🏆 Before & After

Before Dripsy ☹️

This is what it took to make one responsive style without Dripsy...

import { useState } from 'react'
import { View } from 'react-native'

const ResponsiveBox = () => {
  const [screenWidth, setScreenWidth] = useState(Dimensions.get('window').width)

  useEffect(() => {
    const onResize = (event) => {
      setScreenWidth(event.window.width)
    }
    Dimensions.addEventListener('change', onResize)

    return () => Dimensions.removeEventListener('change', onResize)
  }, [])

  let width = '100%'
  if (screenWidth > 700) {
    width = '50%'
  }

  return <View style={{ width }} />
}

A big issue with using JS-only breakpoints like that is that it won't work on SSR apps using Expo + Next.js. The "solution" would be to lazy load the component, but then you lose the SEO benefits of Next.js. With Dripsy, SSR works fine!

With Dripsy 🤩

import { View } from 'dripsy'

const ResponsiveBox = () => {
  return <View sx={{ width: ['100%', '50%'] }} />
}

API

🚨 More docs coming here!!!

styled

import { View } from 'react-native'
import { styled } from 'dripsy'

const StyledView = styled(View)({
  flex: 1,
  bg: 'primary',
})

// This uses the theme.layout.container styles!
const StyledView2 = styled(View, {
  themeKey: 'layout',
  defaultVariant: 'container',
})({
  flex: 1,
  bg: 'primary',
})

createThemedComponent

Prefer styled.

Currently, a bunch of the React Native components are supported. That said, I haven't added them all. If you want to add one, go to src/components and add one and submit a PR.

Or, you can use the createThemedComponent function in your own app.

import { createThemedComponent } from 'dripsy'
import { View } from 'react-native'

const CustomView = createThemedComponent(View, {
  defaultStyle: {
    flex: 1,
  },
})

Using Custom Fonts [New! 🏄‍♂️]

Dripsy lets you globally control your fonts in React Native. Before Dripsy, this was a huge pain. You had to manually set the fontFamily name to a string that corresponds to your actual font file name. If you ever changed custom fonts, you'd need to edit all your files that had it, or create an unnecessary CustomText component.

No longer. All of your custom font definitions can live in a single theme variable. Once you add your fonts to your theme, you can load them with expo-font (or your loader of choice).

1. Add your font to your theme.fonts

There are two options for this:

a) Provide a single root font in your theme.fonts (easiest, recommended)

b) Provide multiple fonts (only use this if you're using multiple custom fonts)

1.a) Provide a single root in your theme.fonts (easiest, recommended)

const theme = {
  customFonts: {
    arial: {
      // I recommend setting every weight here
      bold: 'arialBold',
      default: 'arial',
      normal: 'arial',
      400: 'arial',
      500: 'arialMedium',
      600: 'arialBold',
      700: 'arialBold',
      800: 'arialBold',
      900: 'arialBlack',
    },
  },
  fonts: {
    root: 'arial', // <- this string must match the key you set in custom fonts above!
  },
}

Recommended when using web, add a fallback for your fonts:

const webFont = (font: string) =>
  Platform.select({
    web: `${font}, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif`,
    default: font,
  })

const theme = {
  customFonts: {
    arial: {
      bold: webFont('arialBold'),
      default: webFont('arial'),
      normal: webFont('arial')',
      '400': webFont('arial')',
      '500': webFont('arialMedium'),
      '600': webFont('arialBold'),
      '700': webFont('arialBold'),
      '800': webFont('arialBold'),
      '900': webFont('arialBlack'),
    },
  },
}

You can also alias your fontWeights to make it easier, just like theme-ui:

const theme = {
  customFonts: {
    arial: {
      bold: 'arialBold',
      default: 'arial',
      normal: 'arial',
      400: 'arial',
      500: 'arialMedium',
      600: 'arialBold',
      700: 'arialBold',
      800: 'arialBold',
      900: 'arialBlack',
    },
  },
  fonts: {
    root: 'arial',
  },
  // this is new here:
  fontWeights: {
    black: '900',
  },
}

Now that we've added the black shorthand to our fontWeights, we can use it anywhere in our app. The string 900 corresponds to theme.customFonts.arial['900'].

You can now style your fonts like so:

import { Text } from 'dripsy'

const Black = () => (
  <Text sx={{ fontWeight: 'black' }}>This font weight is 900!</Text>
)

You can also use this shorthand when creating custom text variants in your theme. For instance, if you want to make a bold & caps text variant:

const theme = {
  ...
  fontWeights: {
    black: '900'
  },
  text: {
    thickCaps: {
      fontWeight: 'black',
      textTransformation: 'uppercase'
    }
  }
}
import { Text } from 'dripsy'

const BoldCaps = () => (
  <Text variant="thickCaps">This font weight is 900, & it's capitalized!</Text>
)

Considerations for naming conventions

Notice how the theme.fonts.root is arial. This tells Dripsy to check for theme.customFonts.arial. If you wanted to name it something different, you could. However, you can't name it root. That's the only exception.

There are 2 important details when it comes to the naming:

  1. The name of your customFont must match the name you pass to theme.fonts.root. In the example above, I picked the name arial.
  2. The name you use to load in your font at its default weight (often 400 or default) must also match the key you pass to theme.customFonts.
  • Explanation In step 2, when you import your font using expo-font, you have to make sure you name the default font weight with the same name passed to customFonts.
  • In the example above, we would import our font using expo-font, and name it arial. You can skip down to step #3 to see what I mean. We need to make these the same to ensure that we always fall back to the correct default font. If we don't do this, then React Native will raise an error, saying it could not find the custom font.

1b) Provide multiple fonts (only use this if you're using multiple custom fonts)

If you have multiple custom fonts you'd like to use, this step is for you.

  1. Follow the same steps as step #2.a.
  2. Add your other fonts to theme.customFonts, just like step #1a.
const theme = {
  customFonts: {
    arial: {
      ... from step 2.a
    },
    // these are new
    sans: {
      bold: 'sansBold',
      default: 'sans',
      normal: 'sans',
      '400': 'sans',
      '500': 'sans',
      '600': 'sansBold',
      '700': 'sansBold',
      '800': 'sansBold',
      '900': 'sansBlack',
    },
  },
  fonts: {
    root: 'arial',
    heading: 'sans'
  },
  text: {
    h1: {
      // use sans here
      fontFamily: 'heading'
    },
    h2: {
      fontFamily: 'heading'
    },
    h3: {
      fontFamily: 'heading'
    },
  }
}

This tells Dripsy we have 2 custom fonts, named arial and sans. These are custom names made by you. They will be used in your app later to reference which font you're picking.

2. Loading in fonts with expo-font (or whatever loader you prefer)

As an added step (to include in docs later), you can use expo-font to actually load the fonts in:

// fonts.tsx
import React from 'react'
import { useFonts } from 'expo-font'

export default function Fonts({ children }: { children: React.ReactNode }) {
  const [loaded] = useFonts({
    // 🚨🚨🚨 the name (`sans`) of the default weight here should equal the key from theme.customFonts!
    // otherwise, you will need to explicitly set the fontWeight everywhere
    // since we have theme.customFonts.sans, we name this `sans`
    ['sans']: require('./public/fonts/sansBook.ttf'),
    ['sansBold']: require('./public/fonts/arialBlack.ttf'),

    // same goes here, load in the default font name with the one that matches your theme.customFonts
    ['arial']: require('./public/fonts/arialBook.ttf'),
    ['arialBold']: require('./public/fonts/arialBold.ttf'),
  })

  if (!loaded) return null

  return <>{children}</>
}

And then in your app:

// App.tsx
import Fonts from './fonts'

export default function App() {
  return (
    <Fonts>
      <YourAppHere />
    </Fonts>
  )
}

Important note, mentioned in #2.a above. The name of the default font you use in useFonts must match the key for the font in your theme.customFonts. Otherwise, you will get errors, and errors suck.

Another caveat: you cannot name a font "root". Dripsy uses this field to identify your root font, so please do not name a font root when you load it in. Any other word works.

3. Using and customizing your custom fonts in your app

Now that we've defined our fonts in our theme, we can use them anywhere in our app. To globally style all text, you could add a theme.text.body field:

const theme = {
  customFonts: {
    arial: {
      bold: 'arialBold',
      default: 'arial',
      normal: 'arial',
      400: 'arial',
      500: 'arialMedium',
      600: 'arialBold',
      700: 'arialBold',
      800: 'arialBold',
      900: 'arialBlack',
    },
  },
  fonts: {
    root: 'arial',
  },
  text: {
    body: {
      // this edits all <Text> components
      fontWeight: 'bold',
      color: 'cyan',
    },
    h1: {
      // this edits all <H1> components
      fontWeight: '900',
    },
  },
}

You can also style like normal throughout your app, and watch your font weights change elegantly:

import { Text } from 'dripsy'

const Bold = () => (
  <Text>Whoa, this is a custom bold font (& it's color is cyan)</Text>
)

For context, without dripsy, you'd have to do this:

import { Text } from 'react-native'

const Bold = () => (
  <Text style={{ fontFamily: 'arialBold' }}>Lame, this isn't easy.</Text>
)

You probably don't want to make your text.body bold, since this will style your entire app's Text, but you could make a custom variant in theme.text, like so:

const theme = {
  ...,
  text: {
    thick: {
      fontWeight: 'bold'
    }
  }
}

In your component:

import { Text } from 'react-native'

const Thick = () => (
  <Text variant="thick">Hey, this is bold. That's all it takes.</Text>
)

Using custom fonts on web

To improve the performance of loading your fonts on web, you can add something like this to the head of your HTML:

<link
  rel="preload"
  href="/fonts/circ/CircularStd-Book.ttf"
  as="font"
  crossOrigin=""
/>
<link
  rel="preload"
  href="/fonts/circ/CircularStd-Medium.ttf"
  as="font"
  crossOrigin=""
/> 

Create a link for each font you're importing, and make sure to keep the preload prop to make it load early.

If you're using Next.js, this would go in your pages/_document.js file, inside of Next's <Head> component.

How it works

First, this library is super inspired by theme-ui, and uses many of its low-level functions and methodologies.

Practically speaking, this library uses the Dimensions api on Android & iOS, and uses actual CSS breakpoints on web. The CSS breakpoints are made possible by @artsy/fresnel. This means that you get actually-native web breakpoints. That matters, because server-size rendered apps will have startup issues if you use JS-based media queries that require React to rehydrate on when it opens.

On Native, there is nothing too fancy going on. We track the screen width, generate styles based on the current width using a mobile-first approach, and return the regular React Native components. But it just feels like magic! Plus, you get all the awesome theming abilities baked in. If you're using this in native, the theming alone is a great use case.

Contributing

This is a really new project. I'd love your help and contributions.

License

MIT