{...}"; 2. Set by "handleSelectkeys(e){...}" Selected state; 3. Use "oli.push(
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React method to implement a three-level menu: 1. The method to create and expand the three-level parent menu is "onOpenChange = (openKeys) => {...}"; 2. Through "handleSelectkeys(e) {...}" to set the selected state; 3. Generate the sidebar through "oli.push(
The operating environment of this tutorial: Windows 10 system, react version 18.0.0, Dell G3 computer.
How to implement a three-level menu in react?
react antd implements only expanding the sidebar of a parent menu bar (three-level menu bar)
Encountered at work One requirement is that the three-level sidebar can only expand a parent menu bar to keep the page simple and improve the user experience. I also searched online for a long time and found nothing that fully met the requirements, so I combined other people's own and wrote one... .
How to expand the three-level parent menu
onOpenChange = (openKeys) => { const latestOpenKey = openKeys.find(key => this.state.openKeys.indexOf(key) === -1); let openList; if(this.state.rootSubmenuKeys.indexOf(latestOpenKey) === -1) { if(latestOpenKey&&latestOpenKey.length===3){ openList = this.state.openKeys.filter((e)=>{ return e.length!==3; }) this.setState({ openKeys:openList }); }else{ this.setState({ openKeys:openKeys }); } }else{ if(latestOpenKey&&latestOpenKey.length===3){ openList = this.state.openKeys.filter((e)=>{ return e.length!==3; }) openList.push(latestOpenKey); this.setState({ openKeys:openList[1] ? openList : [openList[0],openList[2]] }); }else{ this.setState({ openKeys: latestOpenKey ? [latestOpenKey] : [], }); } } }</p> <p><strong>Set the selected state</strong></p> <pre class="brush:php;toolbar:false"> handleSelectkeys(e){ if(this.state.isShow){ this.setState({ selectedKey:e.key, openKeys:e.keyPath[length] == 3 ? [e.keyPath[2],e.keyPath[1]] : [e.keyPath[0]], isShow:true }); } }
Generate the side Column
const data = this.props.list; var html = []; for(var i=0;i<data.length;i++){ if(data[i].children){ var li = [] for(var j=0;j<data[i].children.length;j++){ var liData = data[i].children[j]; if(liData.children){ var oli = []; for(var k=0;k<liData.children.length;k++){ oli.push( <Menu.Item key={liData.children[k].url}> <Link to={ { pathname:liData.children[k].url, state:{//三级菜单下传openKeys传两个值,展开两级 parent:this.state.openKeys[0], child:this.state.openKeys[1] } } }> <span>{liData.children[k].text}</span> </Link> </Menu.Item> ) } var oul = <SubMenu key={liData.id} title={<span>{liData.iconCls && <Icon type={liData.iconCls} />}<span>{liData.text}</span></span>}>{oli}</SubMenu>; li.push(oul); }else{ li.push( <Menu.Item key={liData.url}> <Link to={ { pathname:liData.url, state:{//二级菜单下openKeys传一个值,展开一级 parent:this.state.openKeys[0], // child:this.state.openKeys[1] ? this.state.openKeys[1] : '' } } } > {liData.iconCls && <Icon type={liData.iconCls} />} <span>{liData.text}</span> </Link> </Menu.Item> ); } } var ul = <SubMenu key={data[i].id} title={<span>{data[i].iconCls && <Icon type={data[i].iconCls} />}<span>{data[i].text}</span></span>}>{li}</SubMenu>; html.push(ul); }else{ html.push( <Menu.Item key={data[i].url}> <Link to={ { pathname:data[i].url, state:{//一级菜单下传空值,不展开菜单栏 parent:'' } } } > {data[i].iconCls && <Icon type={data[i].iconCls} />} <span>{data[i].text}</span> </Link> </Menu.Item> ) } }
Sidebar component Menu.js All code
import React from 'react'import { Menu,Icon } from 'antd';import {Link,withRouter} from 'react-router-dom'const { SubMenu } = Menu; class Menus extends React.Component{ constructor(props){ super(props) this.state={ openKeys:['1','100'], rootSubmenuKeys:[], selectedKeys:[this.props.history.location.pathname], //选中 isShow:false //判断是否已经展开,如已展开停止重新赋值避免重新渲染和关系菜单 } this.handleSelectkeys = this.handleSelectkeys.bind(this) } UNSAFE_componentWillMount(){ if(this.props.location.state){ this.setState({ openKeys:[this.props.location.state.parent,this.props.location.state.child ? this.props.location.state.child : ''] }) } } componentDidMount(props,nextProps){ var data = this.props.list; for(var i=0;i{ const latestOpenKey = openKeys.find(key => this.state.openKeys.indexOf(key) === -1); let openList; if(this.state.rootSubmenuKeys.indexOf(latestOpenKey) === -1) { if(latestOpenKey&&latestOpenKey.length===3){ openList = this.state.openKeys.filter((e)=>{ return e.length!==3; }) this.setState({ openKeys:openList }); }else{ this.setState({ openKeys:openKeys }); } }else{ if(latestOpenKey&&latestOpenKey.length===3){ openList = this.state.openKeys.filter((e)=>{ return e.length!==3; }) openList.push(latestOpenKey); this.setState({ openKeys:openList[1] ? openList : [openList[0],openList[2]] }); }else{ this.setState({ openKeys: latestOpenKey ? [latestOpenKey] : [], }); } } } render(){ const data = this.props.list; var html = []; for(var i=0;i<data.length;i++){ if(data[i].children){ var li = [] for(var j=0;j<data[i].children.length;j++){ var liData = data[i].children[j]; if(liData.children){ var oli = []; for(var k=0;k<liData.children.length;k++){ oli.push( <Menu.Item key={liData.children[k].url}> <Link to={ { pathname:liData.children[k].url, state:{//三级菜单下传openKeys传两个值,展开两级 parent:this.state.openKeys[0], child:this.state.openKeys[1] } } }> <span>{liData.children[k].text}</span> </Link> </Menu.Item> ) } var oul = <SubMenu key={liData.id} title={<span>{liData.iconCls && <Icon type={liData.iconCls} />}<span>{liData.text}</span></span>}>{oli}</SubMenu>; li.push(oul); }else{ li.push( <Menu.Item key={liData.url}> <Link to={ { pathname:liData.url, state:{//二级菜单下openKeys传一个值,展开一级 parent:this.state.openKeys[0], // child:this.state.openKeys[1] ? this.state.openKeys[1] : '' } } } > {liData.iconCls && <Icon type={liData.iconCls} />} <span>{liData.text}</span> </Link> </Menu.Item> ); } } var ul = <SubMenu key={data[i].id} title={<span>{data[i].iconCls && <Icon type={data[i].iconCls} />}<span>{data[i].text}</span></span>}>{li}</SubMenu>; html.push(ul); }else{ html.push( <Menu.Item key={data[i].url}> <Link to={ { pathname:data[i].url, state:{//一级菜单下传空值,不展开菜单栏 parent:'' } } } > {data[i].iconCls && <Icon type={data[i].iconCls} />} <span>{data[i].text}</span> </Link> </Menu.Item> ) } } return ( ) }}export default withRouter(Menus);
Sidebar data menu.js
const list = [ { "id":1, "text":"检查清单", "state":"closed", "iconCls":"home", "children":[ { "id":100, "text":"按月检查", "checked":false, "state":"closed", "iconCls":"", "url":"/platform/check/month" }, { "id":101, "text":"按年检查", "checked":false, "state":"closed", "iconCls":"", "url":"/platform/check/year" } ] }, { "id":2, "text":"数据预览导出", "iconCls":"laptop", "state":"closed", "checked":true, "children":[ { "id":200, "text":"做的书", "iconCls":"", "state":"closed", "checked":true, "children":[ { "id":20001, "text":"2018做的书", "iconCls":" ", "url":"/platform/export/makeBook/2018" }, { "id":20002, "text":"2019做的书", "iconCls":" ", "url":"/platform/export/makeBook/2019" }, { "id":20003, "text":"2020做的书", "iconCls":" ", "url":"/platform/export/makeBook/2020" } ] }, { "id":201, "text":"财务收入", "iconCls":"", "state":"closed", "checked":true, "children":[ { "id":20101, "text":"2018财务收入", "iconCls":" ", "url":"/platform/export/GMV/2018" }, { "id":20102, "text":"2019财务收入", "iconCls":" ", "url":"/platform/export/GMV/2019" }, { "id":20103, "text":"2020财务收入", "iconCls":" ", "url":"/platform/export/GMV/2020" }, ] }, { "id":202, "text":"财务支出", "iconCls":"", "state":"closed", "checked":true, "children":[ { "id":20201, "text":"2018财务支出", "iconCls":" ", "url":"/platform/export/expend/2018" }, { "id":20202, "text":"2019财务支出", "iconCls":" ", "url":"/platform/export/expend/2019" }, { "id":20203, "text":"2020财务支出", "iconCls":" ", "url":"/platform/export/expend/2020" }, ] }, ] }, ]class SiderNav extends React.Component { render() { return ( <Sider width={230} breakpoint className="AdminSider"> <Menus list={list} /> </Sider> ) }}```
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