Introduction

Zero Theme is Zero Molecule's new approach to React Native styling which can be overwhelming from time to time. We wanted to be able to use css-like className styling instead of writing {flex: 1} a million times. Yes, we know this can all be achieved using plain JavaScript, but we prefer this way for it's simplicity and readability.

Note

This is a pure styling library, not a UI kit. It is compatible with any component and UI kit available. If you're looking for a UI kit, please check out our zero-components UI kit for React Native

Features

• Global style (theme) containing all classes that themed components use
• A way to set default component styles
• Support for other styling properties like contentContainerStyle
• Flow typed props
• Utility and parsing functions so you can use them for yourself
• withTheme High-Order Component that enables you to wrap any component and make it themeable
• BEM inspired way to have subclasses

Getting started

Installation

If you want just the components, you need to add the plugin from npm.js using

npm install react-native-zero-theme --save

or if you prefer yarn

yarn add react-native-zero-theme

Create your theme

Your theme is actually a collection of css-like classes and some BEM-like blocks with substyles. Simple theme looks something like this:

export default {
  flex: {
    flex: 1,
  },
  flexGrow: {
    flexGrow: 1,
  },
  'p-24': {
    padding: 24,
  },
  text: {
    color: '#333',
    fontSize: 14,
    '--bold': {
      fontWeight: 'bold',
    },
    '--center': {
      textAlign: 'center',
    },
    '--error': {
      textColor: 'red',
    },
  },
  background: {
    backgroundColor: '#f1f1f1',
    '--dark': {
      backgroundColor: '#333',
    },
    '--light': {
      backgroundColor: '#fff',
    },
  },
};

Here you can see that we've added few global classes for all components to use (like flex, and p-24). In addition to those, we also added come block specific classes like text and background which have their own styles and subclasses. Their usage is shown below.

Usage

Basic

If you just want to wrap your component and maybe set some default classes to it, you use it like this

import React from 'react';
import { ScrollView, Text, View } from 'react-native';
import { Theme, withTheme } from 'react-native-zero-theme';
import showcaseTheme from './showcaseTheme';

const ThemedView = withTheme()(View);
const ThemedText = withTheme({ className: ['style', 'text'] })(Text);
const ThemedScrollView = withTheme({
  className: ['style'],
  contentContainerClassName: ['contentContainerStyle'],
})(ScrollView);

const BasicShowcase = () => (
  <Theme.Provider value={showcaseTheme}>
    <ThemedScrollView className="flex" contentContainerClassName="flex flex-grow">
      <ThemedView className="center flex p-24">
        <ThemedText>
          My font size is 14 and color is #333
        </ThemedText>
        <ThemedText className="text--error">
          There is danger ahead! I look just like text above, but my text is red
        </ThemedText>
        <ThemedText className="p-24 text--center text--bold">
          Well that is all good for you, but I am in the center of attention!
        </ThemedText>
      </ThemedView>
    </ThemedScrollView>
  </Theme.Provider>
);

License

Zero Theme is open source and released under the BSD-3-Clause License