React实现全局组件的Toast轻提示效果

来源：jb51　　时间：2018/9/25 19:02:27　　对本文有异议

Toast是常用的轻提示弹框，常用于页面loading和提示语弹窗。

本例基于React实现一个随时可调用且不随页面渲染的全局组件。

需求分析

Toast 不需要同页面一起被渲染，而是根据需要被随时调用。
Toast 是一个轻量级的提示组件，它的提示不会打断用户操作，并且会在提示的一段时间后自动关闭。
Toast 需要提供几种不同的消息类型以适应不同的使用场景。
Toast 的方法必须足够简洁，以避免不必要的代码冗余。

如何使用

首先引入

import Toast from './components/toast'

JSX中事件调用：

<button onClick={() => { Toast.info('普通提示') }}>普通提示</button>

JS中方法调用：

Toast.info('普通提示')

回调方法：

const hideLoading = Toast.loading('加载中...', 0, () => {
  Toast.success('加载完成')
})
setTimeout(hideLoading, 2000)

调用规则：

3个参数：

content 提示内容 string（loading方法为可选）
duration 提示持续时间 number，单位ms（可选）
onClose 提示关闭时的回调函数（可选）

Toast.info("普通",2000)
Toast.success("成功",1000,() => {
  console.log('回调方法')
}))
Toast.error("错误")
Toast.loading()

代码实现

目录结构：

index.js：对外export接口，设置默认的参数值，全局创建或销毁Toast的DIV。
toast.js：Toast具体显示的内容及多次调用Toast时的状态管理。
toast.css：Toast的样式，费话不多说。

index.js：

import React from 'react'
import ReactDOM from 'react-dom'
import Toast from './toast'
import './toast.css'
 
function createNotification() {
  const div = document.createElement('div')
  document.body.appendChild(div)
  const notification = ReactDOM.render(<Toast />, div)
  return {
    addNotice(notice) {
      return notification.addNotice(notice)
    },
    destroy() {
      ReactDOM.unmountComponentAtNode(div)
      document.body.removeChild(div)
    }
  }
}
 
let notification
const notice = (type, content, duration = 2000, onClose) => {
  if (!notification) notification = createNotification()
  return notification.addNotice({ type, content, duration, onClose })
}
 
export default {
  info(content, duration, onClose) {
    return notice('info', content, duration, onClose)
  },
  success(content = '操作成功', duration, onClose) {
    return notice('success', content, duration, onClose)
  },
  error(content, duration , onClose) {
    return notice('error', content, duration, onClose)
  },
  loading(content = '加载中...', duration = 0, onClose) {
    return notice('loading', content, duration, onClose)
  }
}

toast.js：

import React, { Component } from 'react'
 
class ToastBox extends Component {
  constructor() {
    super()
    this.transitionTime = 300
    this.state = { notices: [] }
    this.removeNotice = this.removeNotice.bind(this)
  }
 
  getNoticeKey() {
    const { notices } = this.state
    return `notice-${new Date().getTime()}-${notices.length}`
  }
 
  addNotice(notice) {
    const { notices } = this.state
    notice.key = this.getNoticeKey()
 
    // notices.push(notice);//展示所有的提示
    notices[0] = notice;//仅展示最后一个提示
    
    this.setState({ notices })
    if (notice.duration > 0) {
      setTimeout(() => {
        this.removeNotice(notice.key)
      }, notice.duration)
    }
    return () => { this.removeNotice(notice.key) }
  }
 
  removeNotice(key) {
    const { notices } = this.state
    this.setState({
      notices: notices.filter((notice) => {
        if (notice.key === key) {
          if (notice.onClose) setTimeout(notice.onClose, this.transitionTime)
          return false
        }
        return true
      })
    })
  }
 
  render() {
    const { notices } = this.state
    const icons = {
      info: 'toast_info',
      success: 'toast_success',
      error: 'toast_error',
      loading: 'toast_loading'
    }
    return (
      <div className="toast">
        {
          notices.map(notice => (
            <div className="toast_bg" key={notice.key}>
              <div className='toast_box'>
                <div className={`toast_icon ${icons[notice.type]}`}></div>
                <div className='toast_text'>{notice.content}</div> 
              </div>
            </div>
          ))
        }
      </div>
    )
  }
}
 
export default ToastBox

toast.css:

.toast {
 position: fixed;
 left: 0;
 top: 0;
 z-index: 999;
 display: flex;
 flex-direction: column; }
 .toast_bg {
  position: fixed;
  width: 100%;
  height: 100%;
  left: 0;
  top: 0; }
 .toast_box {
  position: relative;
  left: 50%;
  top: 50%;
  width: 2.8rem;
  height: 2rem;
  margin: -1rem -1.4rem;
  background: rgba(0, 0, 0, 0.65);
  border-radius: .1rem;
  color: #fff; }
 .toast_text {
  position: absolute;
  bottom: 16%;
  text-align: center;
  width: 90%;
  margin: 0 5%;
  height: .28rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap; }
 .toast_icon {
  position: relative;
  left: 50%;
  top: 15%;
  margin: -.4rem;
  width: .8rem;
  height: .8rem; }
 .toast_loading {
  -webkit-animation: loading 1s steps(12, end) infinite;
  animation: loading 1s steps(12, end) infinite;
  background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAMAAABEpIrGAAAAM1BMVEUAAAD///////////////////////////////////////////////////////////////+3leKCAAAAEHRSTlMAENCA8KAgsGDgQMCQUDBwhylaLQAAAL1JREFUOMu9U0kSwyAMK9jsS/T/1zZt2pgEZzq9RBeMZYRGDI/70bO5JptjrOAQVTonIJVK5bW2ma9A7VvpK8OdeQfbZectrDnyU+Oo0b68wGK0muDPdxpOciaizq5pkAgiIPAoew2rBVNYZoM2YHbZDNKz/2Ogam3ff5gMEL8wisfh2KKZiFiGWFkk1B7NSbhNQFy4M2+PghbODNsg7y8THM2njiy8gBgcaEUA9GgNJbxh6fJv+NxiFvYmPAFtCQZNK1qZIAAAAABJRU5ErkJggg==") no-repeat;
  background-size: 100%; }
 .toast_success {
  background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgCAMAAABEpIrGAAAAM1BMVEUAAAD///////////////////////////////////////////////////////////////+3leKCAAAAEHRSTlMA8DAQ0GBP4LCggMBwIJBAIttdjAAAAINJREFUOMvdkUsOwyAMBbH5hUCauf9pK1SlohF438x2LPn52f09+8vUfiNb/gighj8FouEjYCUoQDXiBSD7pdcMiK7XC9wCFmlDO3T20Scgx287ne13pwDU89NOJ3g3maCmJDANqIGRtLj8oi1ed1GMdmcB7wXIYX8QdQZJiM5Em3smbyVICDCOrCqSAAAAAElFTkSuQmCC") no-repeat;
  background-size: 100%; }
 .toast_error {
  background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgBAMAAACBVGfHAAAAMFBMVEUAAAD///////////////////////////////////////////////////////////87TQQwAAAAD3RSTlMA0BDAMODwUKBgsCCAQJClzVPvAAAA0UlEQVQoz2MgErAclv9o44Dgc8b/B4KvBTA+t/3XdgeWivjPG6ACbl8ngNXlp0AN+L8IwtD6DzFm2w+Y3v5sMGW/ACbA9Rms9ZsCTIApH2QR608GhoUKQJ4xA8P8AKCAP5CwF2JgUPwIlPwCFDj/AMRRYJIHCnL8AZkJ1AfkAcUYGNhBpso7MICUgBQw8H4EEv/B5ssDFYA4mAKYWjANfd+Aai3CYZ9BDoM63RDkdEGQ0zE9h+l9zADCDEIGt2/wQEZEwwVepGhgYEdEFGZUEgYAW05XI3jSsVwAAAAASUVORK5CYII=") no-repeat;
  background-size: 100%; }
 .toast_info {
  background: url("data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAACAAAAAgBAMAAACBVGfHAAAALVBMVEUAAAD///////////////////////////////////////////////////////+hSKubAAAADnRSTlMA4CCAwKBAMJBg8NAQUNhWlbcAAAC+SURBVCjPYyASsLfse+1cgOBzyr0DgocXYHwmv4dtCkwZck8UoAJZDydA1C2H8NnexUAYR99BjNF6CtMbtwhM+QUACUUhIMH6BKz14QEgafcYSPDIgSxifMkAE2CYJwAk6gQQAozPgURfA0KAA0T6JSAE2ECm7lNACDC9BhLvGGACIA6GAFyLohBEC9xQqLeeQKwFA4i1EIfBAeNzuNMVhSBOx/AcpvcxAwgzCDEDGTMaGHhhEYWIShN4VBIGAPvRT5YzufhUAAAAAElFTkSuQmCC") no-repeat;
  background-size: 100%; }
 
@-webkit-keyframes loading {
 0% {
  -webkit-transform: rotate3d(0, 0, 1, 0deg);
  transform: rotate3d(0, 0, 1, 0deg); }
 100% {
  -webkit-transform: rotate3d(0, 0, 1, 360deg);
  transform: rotate3d(0, 0, 1, 360deg); } }
 
@keyframes loading {
 0% {
  -webkit-transform: rotate3d(0, 0, 1, 0deg);
  transform: rotate3d(0, 0, 1, 0deg); }
 100% {
  -webkit-transform: rotate3d(0, 0, 1, 360deg);
  transform: rotate3d(0, 0, 1, 360deg); } }