skeleton在心意web上的实践

通过手动编写skeleton，在fetch数据时显示skeleton loading，数据拉取成功隐藏skeleton

先看下效果图

在component下创建页面对应的skeleton，然后通过在index.js中export输出，在需要使用skeleton的页面中引入。

代码结构

charity-web
       |--- components
      		    |---Skeleton
 |---HomeProject.js    home页项目列表
 |---index.js    导出所有skeleton
 |---ProjectCard.js    项目列表item
 |---HomeListing.js   项目列表页
       |--- pages
      		    |---index.js
      		    |---listing.js
       |--- redux
      		    |---app
      		    |---project
      		    |---index.js
      		    |---rootSaga.js

skeleton部分代码

• skeleton/index.js文件

import HomeProjectSkeleton from './HomeProject'
import ProjectListingSkeleton from './ProjectListing'
import PromotionItemSkeleton from './PromotionItem'
export { PromotionItemSkeleton, HomeProjectSkeleton, ProjectListingSkeleton }

• skeleton/homeproject.js文件

import { Col, Row } from 'antd'
import React, { Component } from 'react'
import styled from 'styled-components'
import mediaQuery from '../../utils/mediaQuery'
import ProjectCard from './ProjectCard'
const Container = styled.div`
  .projects {
    padding-top: 32px;
    ${mediaQuery.tablet} {
      padding-top: 24px;
    }
    ${mediaQuery.mobile} {
      padding-top: 24px;
    }
  }
  .projectWrapper {
    padding-bottom: 24px;
  }
`
class HomeProject extends Component {
  render() {
    const items = [0, 1, 2, 3, 4]
    return (
      <Container>
        <div className='projects'>
          <div className='max-width'>
            <Row type='flex' justify='start' gutter={24}>
              {items.map(i => {
                return (
                  <Col
                    xs={24}
                    md={12}
                    xl={8}
                    className='projectWrapper'
                    key={`p_${i}`}
                  >
                    <ProjectCard />
                  </Col>
                )
              })}
            </Row>
          </div>
        </div>
      </Container>
    )
  }
}
export default HomeProject

• skeleton/projectlisting.js文件

import { Col, Row } from 'antd'
import React, { Component } from 'react'
import ProjectCard from './ProjectCard'
class ProjectListing extends Component {
  render() {
    const items = [0, 1, 2, 3, 4]
    return (
      <Row type='flex' justify='start' gutter={24}>
        {items.map(i => {
          return (
            <Col
              xs={24}
              md={24}
              xl={24}
              className='projectWrapper'
              key={`p_${i}`}
            >
              <ProjectCard listStyle />
            </Col>
          )
        })}
      </Row>
    )
  }
}
export default ProjectListing

• skeleton/promotionitem.js文件

import React, { Component } from 'react'
import styled from 'styled-components'
import mediaQuery from '../../utils/mediaQuery'
const Container = styled.div`
  width: 100vw;
  height: 37.5vw;
  background-color: #f4f4f4;
  ${mediaQuery.mobile} {
    height: 56.25vw;
  }
`
class PromotionItem extends Component {
  render() {
    return <Container />
  }
}
export default PromotionItem

在页面中应用skeleton

1、首先引入skeleton

import {
  HomeProjectSkeleton,
  PromotionItemSkeleton
} from '../components/Skeleton/index'

2、在render函数中，通过 this.props.isFetching判断是否显示skeleton

{process.env.usePromoItem ? (
          this.props.isFetching ? (
            <PromotionItemSkeleton />
          ) : (
            <Swiper slides={this.props.promoItems} />
          )
        ) : (
          this.renderHeroProject()
        )}
        {this.props.isFetching ? (
          <HomeProjectSkeleton />
        ) : (
          (this.renderHighlightedProjects(), this.renderOtherProjects())
        )}

3、在reduces.js中，当getHomePageDataRequest拉取数据的时候，设置isFetching为true，getHomePageDataSucceeded获取成功后，将isFetching修改为false

import {
  getHomePageDataRequest,
  getHomePageDataSucceeded,
} from './actions'
export const projectInitialState = {
  fetching: {
    getHomepageData: false,
    getSearchListingPageData: false
  }
}
const projectReducer = handleActions(
  {
    [getHomePageDataRequest]: state => {
      return {
        ...state,
        fetching: {
          getHomepageData: true
        }
      }
    },
    [getHomePageDataSucceeded]: (state, action) => {
      return {
        ...state,
        fetching: {
          getHomepageData: false
        }
      }
    },
  }
  projectInitialState
)
export default projectReducer

4、这样，在页面中mapStateToProps中我们可以拿到isFetching的状态，从而在数据获取成功之前显示skeleton

const mapStateToProps = ({ appState, projectState, paymentState }, props) => ({
  isFetching: projectState.fetching.getHomepageData
})

总结

以上，就是对skeleton在项目中的应用，当然通过以上这种方式实现的skeleton，有一个不好的地方是，如果页面结构变化，我们同时也需要更新sekleton的结构，这是比较麻烦的地方。