react实现移动端下拉菜单

获取dom元素，动态修改选中dom的innerHtml。
当然这种方式不是react推荐的

既然react不推荐直接操作dom元素，那可以采用动态动态修改class的方式达到效果，例如：
let cls ="normal"
div未被选中时
<div className={cls}/> 
div被选中时
cls+=" current"
<div className ={cls}>

作者：米亚流年
链接：https://juejin.cn/post/6844904048965976072
来源：掘金
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

let tabs = {};
tabs[TABKAY.AREA] = {
key: TABKAY.AREA,
text: "全部区域",
obj: {}
};
tabs[TABKAY.SORT] = {
key: TABKAY.SORT,
text: "综合排序",
obj: {}
};
tabs[TABKAY.FILTER] = {
key: TABKAY.FILTER,
text: "筛选",
obj: SX
};
const initialState = {
areas: [{ id: "", name: "全部区域" }],
tabs: tabs,
actionKey: TABKAY.AREA,// 标识了当前选中tab
closePanel: true // 标识panel div 是否显示
};

作者：米亚流年
链接：https://juejin.cn/post/6844904048965976072
来源：掘金
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

renderTabs() {
const { tabs, actionKey, closePanel } = this.props;
//---------
if (!closePanel) {
  fixedBody();
} else {
  looseBody();
}
//---------

let aray = [];
for (let key in tabs) {
  let item = tabs[key];
  let cls = item.key + " item";
  if (item.key === actionKey && !closePanel) {
    cls += " current";
  }

  aray.push(
    <div className={cls} key={item.key} onClick={() => this.onChangeTab(item.key)}>
      {item.text}
    </div>);
}

return aray;
}

作者：米亚流年
链接：https://juejin.cn/post/6844904048965976072
来源：掘金
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

.item {
flex: 1;
font-size: 15px;
border-right: 0.5px solid #eaeaea;
text-align: center;

&:last-child {
  border: none;
}

&.AREA:after, &.SORT:after, &.FILTER:after {
  content: "";
  display: inline-block;
  width: 5px;
  height: 5px;
  margin-bottom: 2px;
  margin-left: 6px;
  border: 2px solid #666;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
  -webkit-transform: rotate(45deg);
  -webkit-transition: .3s;
  transition: .3s;
}

&.current {
  color: #0084ff;
}

&.current:after {
  border-color: #0084ff;
  transform: rotate(225deg);
  -webkit-transform: rotate(225deg);
}

作者：米亚流年
链接：https://juejin.cn/post/6844904048965976072
来源：掘金
著作权归作者所有。商业转载请联系作者获得授权，非商业转载请注明出处。

/**
 * Class:
 * Author: miyaliunian
 * Date: 2019/5/26
 * Description:  tabs 选择器
 *  医院列表
 */
import React, { Component } from "react";
import { ZHPX, TABKAY } from "@api/Constant";
//Util
import { fixedBody, looseBody } from "@utils/fixRollingPenetration";
//Redux
import { connect } from "react-redux";
import { bindActionCreators } from "redux";
import { actions as tabActions, getTabs, getAreasList, getActionKey, getClosePanel } from "@reduxs/modules/tabs";
import { actions as hospitalActions,} from "@reduxs/modules/hospital";

//样式
import "./tabs.less";

class Tabs extends Component {
  
  /**
   *  变化当前点击的item状态 同时filter 请求
   * @param filterItem  当前选中的元素
   * @param key   哪个tab是选中状态
   */
  changeDoFilter(filterItem, key, event) {
    const { tabActions: { changeFilter }, hospitalActions:{filterHosiContentList} } = this.props;
    event.stopPropagation();
    changeFilter(filterItem, key, (filter) => {
      filterHosiContentList(filter);
    });
  }

  /**
   * 筛选tab确定按钮
   * @param event
   */
  filterPanel(event) {
    const {tabActions:{closePanelAction}, tabs,hospitalActions:{filterHosiContentList}} = this.props;
    event.stopPropagation();
    closePanelAction(()=>{
      filterHosiContentList(tabs)
    })
  }

  /**
   * 点击切换Tab
   * @param key
   */
  onChangeTab(key) {
    const { actionKey,tabActions: { changeTab }  } = this.props;
    let closePanel = false;
    //如果前后点击的是同一个tab 就关闭panel
    if (actionKey === key && !this.props.closePanel) {
      closePanel = true;
    }
    closePanel ? looseBody() : fixedBody();
    changeTab(key, closePanel);
  }

  /**
   * 渲染顶部tab
   */
  renderTabs() {
    const { tabs, actionKey, closePanel } = this.props;
    //---------
    if (!closePanel) {
      fixedBody();
    } else {
      looseBody();
    }
    //---------

    let aray = [];
    for (let key in tabs) {
      let item = tabs[key];
      let cls = item.key + " item";
      if (item.key === actionKey && !closePanel) {
        cls += " current";
      }

      aray.push(
        <div className={cls} key={item.key} onClick={() => this.onChangeTab(item.key)}>
          {item.text}
        div>);
    }

    return aray;
  }

  /**
   * 全部区域
   * @returns {*}
   */
  renderAreaContent() {
    const { areasList } = this.props;
    return areasList.map((item, index) => {
      let cls = item.active + " area-item";
      return (
        <li key={index} className={"area-item"} onClick={(e) => this.changeDoFilter(item, TABKAY.AREA, e)}>
          {item.name}
        li>
      );
    });
  }


  /**
   * 全部排序
   * @returns {any[]}
   */
  renderSORTContent() {
    let sortList = ZHPX;
    return sortList.map((item, index) => {
      let cls = item.action ? "type-item active" : "type-item";

      return (
        <li key={index} className={cls} onClick={(e) => this.changeDoFilter(item, TABKAY.SORT, e)}>
          {item.name}
        li>
      );
    });
  }


  /**
   * 筛选
   * @returns {*}
   */

  renderFilterInnerContent(items/*filterList*/) {
    return items.map((item, index) => {
      let cls = "cate-box";
      if (item.active) {
        cls += " active";
      }

      return (
        <div key={index} className={cls} onClick={(e) => this.changeDoFilter(item, TABKAY.FILTER, e)}>
          {item.name}
        div>
      );
    });

  }

  renderFILTERContent() {
    let filterList = [];
    const { tabs } = this.props;
    filterList = tabs[TABKAY.FILTER].obj;
    return filterList.map((item, index) => {
      return (
        <li key={index} className={"filter-item"}>
          <p className={"filter-title"}>{index == 0 ? `医院类型: ${item.groupTitle}` : `医院等级: ${item.groupTitle}`}p>
          <div className={"item-content"}>
            {this.renderFilterInnerContent(item.items, filterList)}
          div>
        li>
      );
    });
  }

  /**
   * 渲染过滤面板
   */
  renderContent() {
    const { tabs, actionKey } = this.props;
    let array = [];
    for (let key in tabs) {
      let item = tabs[key];
      let cls = item.key + "-panel";
      if (item.key === actionKey) {
        cls += " current";
      }

      // 全部区域
      if (item.key === TABKAY.AREA) {
        array.push(
          <ul key={item.key} className={cls}>
            {this.renderAreaContent()}
          ul>
        );
      } else if (item.key === TABKAY.SORT) {
        // 综合排序
        array.push(
          <ul key={item.key} className={cls}>
            {this.renderSORTContent()}
          ul>
        );
      } else if (item.key === TABKAY.FILTER) {
        // 筛选
        array.push(
          <ul key={item.key} className={cls}>
            {this.renderFILTERContent()}
            <div className={"filterBtn"} onClick={(e) => this.filterPanel(e)}>
              确定
            div>
          ul>
        );
      }

    }
    return array;
  }


  render() {
    const { closePanel, tabActions: { closePanelAction } } = this.props;
    let cls = "panel";
    if (!closePanel) {
      cls += " show";
    } else {
      cls = "panel";
    }
    return (
      <div className={"tab-header"}>
        <div className={"tab-header-top border-bottom"}>
          {this.renderTabs()}
        div>
        <div className={cls} onClick={() => closePanelAction(()=>{})}>
          <div className={"panel-inner"}>
            {this.renderContent()}
          div>
        div>
      div>
    );
  }


  componentDidMount() {
    const { areasList, tabActions: { loadAreas } } = this.props;
    if (areasList && areasList.length !== 1) {
      return;
    }
    loadAreas();
  }
}

const mapStateToProps = state => {
  return {
    areasList: getAreasList(state),
    tabs: getTabs(state),
    actionKey: getActionKey(state),
    closePanel: getClosePanel(state)
  };
};

const mapDispatchToProps = dispatch => {
  return {
    tabActions: bindActionCreators(tabActions, dispatch),
    hospitalActions: bindActionCreators(hospitalActions, dispatch)
  };
};

export default connect(mapStateToProps, mapDispatchToProps)(Tabs);
复制代码