[React] Use Prop Collections with Render Props

Sometimes you have common use cases that require common props to be applied to certain elements. You can collect these props into an object for users to simply apply to their elements and we'll see how to do that in this lesson.

In short, in Render props partten, you can provide an Object, which contains all the necessary common used props or functions. Then users can just use this single object to multi elements.

// prop collections

import React from 'react'
import {Switch} from '../switch'

class Toggle extends React.Component {
  state = {on: false}
  toggle = () =>
    this.setState(
      ({on}) => ({on: !on}),
      () => this.props.onToggle(this.state.on),
    )
  getStateAndHelpers() {
    return {
      on: this.state.on,
      toggle: this.toggle,
      togglerProps: {
        'aria-pressed': this.state.on,
        onClick: this.toggle,
      },
    }
  }
  render() {
    return this.props.children(this.getStateAndHelpers())
  }
}

function Usage({
  onToggle = (...args) => console.log('onToggle', ...args),
}) {
  return (
    <Toggle onToggle={onToggle}>
      {({on, togglerProps}) => (
        <div>
          <Switch on={on} {...togglerProps} />
          <hr />
          <button aria-label="custom-button" {...togglerProps}>
            {on ? 'on' : 'off'}
          </button>
        </div>
      )}
    </Toggle>
  )
}
Usage.title = 'Prop Collections'

export {Toggle, Usage as default}

TogglerProps is the object we are talking about, it collect all the necessary common used props and functions send by to Render Prop, then this can be used for both <Switch> and <button>

An advantage of using role="button" is that it allows the creation of toggle buttons. A toggle button can have two states: pressed and not pressed. Whether  a button is a toggle button or not can be indicated with the aria-pressed attribute in addition to the button role:

• If aria-pressed is not used the button is not a toggle button.
• If aria-pressed="false" is used the button is a toggle button that is currently not pressed. 
• If aria-pressed="true" is used the button is a toggle button that is currently pressed.
• if aria-pressed="mixed" is used, the button is considered to be partially pressed.