@material-ui/system

Funciones estilizadas de sistema y estilo para construir potentes sistemas de diseño.

Primeros pasos

@material-ui/system provides low-level utility functions called "style functions" for building powerful design systems. Some of the key features:

• ⚛️ Access the theme values directly from the component props.
• 🦋 Encourage UI consistency.
• 🌈 Write responsive style effortlessly.
• 🦎 Trabajar con cualquier objeto temático.
• 💅 Trabaja con las soluciones CSS-en-JS más populares.
• 📦 Menos de 4 KB comprimido.
• 🚀 Rápido suficientemente como para no ser un cuello de botella en tiempo de ejecución.

It's important to understand that this package exposes pure (side-effect free) style functions with this signature: ({ theme, ...style }) => style, that's it.

Demo

In the rest of this Getting Started section we are using styled-components as the reference example (to emphasize the universality of this package). Alternatively, you can use JSS. The demos are also based on the default Material-UI theme object.

Instalación

// usando npm
npm install @material-ui/system

// usando yarn
yarn add @material-ui/system

Crear un componente

In order to use the Box component, you first need to create it. To start with, add a spacing and palette function to the style argument.

import styled from 'styled-components';
import { spacing, palette } from '@material-ui/system';

const Box = styled.div`${spacing}${palette}`;

export default Box;

This Box component now supports new spacing properties and color properties. For instance, you can provide a padding property: p and a color property: color.

<Box p="1rem" color="grey">Give me some space!</Box>

El componente puede ser diseñado proporcionando cualquier valor CSS válido.

Temática

But most of the time, you want to rely on a theme's values to increase the UI consistency. It's preferable to have a predetermined set of padding and color values. Import the theme provider of your styling solution.

import React from 'react'
import { ThemeProvider } from 'styled-components'

const theme = {
  spacing: 4,
  palette: {
    primary: '#007bff',
  },
};

export default function App() {
  return (
    <ThemeProvider theme={theme}>
      {/* children */}
    </ThemeProvider>
  )
}

Now, you can provide a spacing multiplier value:

<Box p={1}>4px</Box>
<Box p={2}>8px</Box>
<Box p={-1}>-4px</Box>

and a primary color:

<Box color="primary">blue</Box>

Todo incluido

To make the Box component more useful, we have been building a collection of style functions, here is the full list:

• borders
• display
• flexbox
• palette
• positions
• shadows
• sizing
• spacing
• typography

If you are already using @material-ui/core, you can use the Box component (using JSS internally):

import Box from '@material-ui/core/Box';

Interoperabilidad

@material-ui/system works with most CSS-in-JS libraries, including JSS, styled-components, and emotion.

If you are already using @material-ui/core, we encourage you to start with the JSS solution to minimize bundle size.

JSS

Styled components

Emotion

Responsivo

All the properties are responsive, we support 3 different APIs. It uses this default, but customizable, breakpoints theme structure:

const values = {
  xs: 0,
  sm: 600,
  md: 960,
  lg: 1280,
  xl: 1920,
};

const theme = {
  breakpoints: {
    keys: ['xs', 'sm', 'md', 'lg', 'xl'],
    up: key => `@media (min-width:${values[key]}px)`,
  },
};

Array

<Box p={[2, 3, 4]} />

/**
 * Outputs:
 *
 * padding: 16px;
 * @media (min-width: 600px) {
 *   padding: 24px;
 * }
 * @media (min-width: 960px) {
 *   padding: 32px;
 * }
 */

Object

<Box p={{ xs: 2, sm: 3, md: 4 }} />

/**
 * Outputs:
 *
 * padding: 16px;
 * @media (min-width: 600px) {
 *   padding: 24px;
 * }
 * @media (min-width: 960px) {
 *   padding: 32px;
 * }
 */

Colocación

If you want to group the breakpoint values, you can use the breakpoints() helper.

import { compose, spacing, palette, breakpoints } from '@material-ui/system';
import styled from 'styled-components';

const Box = styled.div`
  ${breakpoints(
    compose(
      spacing,
      palette,
    ),
  )}
`;

<Box
  p={2}
  sm={{ p: 3 }}
  md={{ p: 4 }}
/>

/**
 * Saídas:
 *
 * padding: 16px;
 * @media (min-width: 600px) {
 *   padding: 24px;
 * }
 * @media (min-width: 960px) {
 *   padding: 32px;
 * }
 */

Props de estilo personalizado

style(options) => style function

Use this helper to create your own style function.

Not all CSS properties are supported. It's possible that you want to support new ones. It's also possible that you want to change the theme path prefix.

Argumentos

1. options (Object):
   • options.prop (String): The property the style function will be triggered on.
   • options.cssProperty (String|Boolean [optional]): Defaults to options.prop. The CSS property used. You can disabled this option by providing false. When disabled, the property value will handle as a style object on it's own. It can be used for rendering variants.
   • options.themeKey (String [optional]): The theme path prefix.
   • options.transform (Function [optional]): Apply a transformation before outputing a CSS value.

Devuelve

style function: The style function created.

Ejemplos

You can create a component that supports some CSS grid properties like grid-gap. By supplying spacing as the themeKey you can reuse logic enabling the behavior we see in other spacing properties like padding.

import styled from 'styled-components';
import { style } from '@material-ui/system';
import { Box } from '@material-ui/core';

const gridGap = style({
  prop: 'gridGap',
  themeKey: 'spacing',
});

const Grid = styled(Box)`${gridGap}`;
const example = <Grid display="grid" gridGap={[2, 3]}>...</Grid>;

You can also customize the prop name by adding both a prop and cssProperty and transform the value by adding a transform function.

import styled from 'styled-components';
import { style } from '@material-ui/system';

const borderColor = style({
  prop: 'bc',
  cssProperty: 'borderColor',
  themeKey: 'palette',
  transform: value => `${value} !important`,
});

const Colored = styled.div`${borderColor}`;
const example = <Colored bc="primary.main">...</Colored>;

compose(...style functions) => style function

Combinar múltiples funciones de estilo en una.

Devuelve

style function: The style function created.

Ejemplos

import { style, compose } from '@material-ui/system'

export const textColor = style({
  prop: 'color',
  themeKey: 'palette',
});

export const bgcolor = style({
  prop: 'bgcolor',
  cssProperty: 'backgroundColor',
  themeKey: 'palette',
});

const palette = compose(textColor, bgcolor);

Variantes

The style() helper can also be used to maps properties to style objects in a theme. In this example, the variant property supports all the keys present in theme.typography.

Propiedad CSS

It will process the css property. If you want to support custom CSS values, you can use the css() helper.

Cómo funciona

styled-system has done a great job at explaining how it works. It can help building a mental model for this "style function" concept.

Real-world use case

In practice, a Box component can save you a lot of time. In this example, we demonstrate how to reproduce a Banner component.

Prior art

@material-ui/system synthesizes ideas & APIs from several different sources:

• Tachyons was one of the first (2014) CSS libraries to promote the Atomic CSS pattern (or Functional CSS).
• Tachyons was later on (2017) followed by Tailwind CSS. They have made Atomic CSS more popular.
• Twitter Bootstrap has slowly introduced atomic class names in v2, v3, and v4. The way they group their "Helper classes" was used as inspiration.
• In the React world, Styled System was one of the first (2017) to promote the style functions. It can be used as a generic Box component replacing the atomic CSS helpers as well as helpers to write new components.
• Large companies such as Pinterest, GitHub, and Segment.io are using the same approach in different flavours:
  • Evergreen Box
  • Gestalt Box
  • Primer Box
• The actual implementation and the object responsive API was inspired by the Smooth-UI's system.