vue+ java 實現多級選單遞迴效果

阿新 • • 發佈：2020-01-07

效果如圖：

大概思路：樹形檢視使用的是vue官方事例程式碼，java負責封裝資料，按照vue官方事例的資料結構封裝資料即可。有兩個需要關注的點：

1.官方事例的資料結構是一個物件裡面包含著集合，而不是一個集合物件 2.遞迴演算法

上程式碼：

前端：html+js

<html>
 <head>
 <meta charset="UTF-8">
 <title></title>
 <script src="https://cdn.jsdelivr.net/npm/[email protected]/dist/vue.js"></script>
 <!-- 引入樣式 -->
 <link rel="stylesheet" href="https://unpkg.com/element-ui/lib/theme-chalk/index.css" rel="external nofollow" >
 <!-- 引入元件庫 -->
 <script src="https://unpkg.com/element-ui/lib/index.js"></script>
 <script src="https://unpkg.com/axios/dist/axios.min.js"></script>
 <script src="${ctx}/core-plugins/ew/depend/jquery/jquery.min.js" type="text/javascript"></script>
<style>
 body {
 font-family: Menlo,Consolas,monospace;
 color: #444;
}
.item {
 cursor: pointer;
}
.bold {
 font-weight: bold;
}
ul {
 padding-left: 1em;
 line-height: 1.5em;
 list-style-type: dot;
}
</style>
<script type="text/x-template" id="item-template">
 <li>
 <div :class="{bold: isFolder}" @click="toggle" @dblclick="makeFolder">
  {{ item.name }}
 
  <span v-if="isFolder">[{{ isOpen ? '-' : '+' }}]</span>
 </div>
 <ul v-show="isOpen" v-if="isFolder">
  <tree-item
  class="item"
  v-for="(child,index) in item.children"
  :key="index"
  :item="child"
  @make-folder="$emit('make-folder',$event)"
  @add-item="$emit('add-item',$event)"
  ></tree-item>
  <li class="add" @click="$emit('add-item',item)">+</li>
 </ul>
 </li>
</script>
</head>
<body>
 
 <div id="demo">
 <ul >
 <tree-item class="item" :item="treeData" @make-folder="makeFolder" @add-item="addItem"> </tree-item>
 </ul>
 </div>
</body>
</html>
<script>
 Vue.component('tree-item',{
 template: '#item-template',props: {
  item: Object 
 },data: function () {
  return {
  isOpen: false
  }
 },computed: {
  isFolder: function () {
  return this.item.children &&
   this.item.children.length
  }
 },methods: {
  toggle: function () {
  if (this.isFolder) {
   this.isOpen = !this.isOpen
  };
  },makeFolder: function () {
  if (!this.isFolder) {
   this.$emit('make-folder',this.item)
   this.isOpen = true
  }
  }
 }
 })
 var demo = new Vue({
 el: '#demo',data: {
  treeData: {}
 },methods: {
  makeFolder: function (item) {
  Vue.set(item,'children',[])
  this.addItem(item)
  },addItem: function (item) {
  item.children.push({
   name: 'new stuff'
  })
  },searchData:function(){
  debugger;
 axios.get('menuRoleLimitBLH_searchMenus.do?pageType=1')
 .then(response => (
  this.treeData = response.data.json.menuMaps
  ))
 .catch(error => console.log(error));
 }
 },created() {
 this.searchData();
  },})
</script>

後臺：java +mysql，一共三個方法，分別是：1.獲取請求 2獲取所有選單 3遞迴選單的父子關係

/**
 * Purpose:選單列表頁面
 * @author JaxWan
 * @param req
 * @return IZrarResponse
 */
 public IZrarResponse searchMenus(IZrarRequest req){
 IZrarResponse res = new ZrarResponse();
 String pageType = req.getParameter("pageType");
 if(StringUtil.isNotNull(pageType)){
 List<EwTreeVO> EwTreeVOs = dao.selectList("selectAllMenuTree");
 List<Map<String,Object>> menus = this.getMenusList(EwTreeVOs);
 Map<String,Object> map = new HashMap<String,Object>();
 map.put("id",1);
 map.put("name",2);
 map.put("children",menus);
 res.addJson("menuMaps",map);
 }else {
 res.addPage("pages/ewsys/dept/menu_role_limit.jsp").addJSTL("isExtForm",false).addJSTL("isEmptyForm",false);
 }
 return res;
 }
/**
 * Purpose:獲取選單集合
 * @author JaxWan
 * @param EwTreeVOs
 * @return List<Map<String,Object>>
 */
 public List<Map<String,Object>> getMenusList(List<EwTreeVO> EwTreeVOs){
 List<Map<String,Object>> menus = new ArrayList<Map<String,Object>>();
 for (int i = 0; i < EwTreeVOs.size(); i++) {
 EwTreeVO ewTreeVO = EwTreeVOs.get(i);
 String id = ewTreeVO.getId();
 String name = ewTreeVO.getName();
 String pId = ewTreeVO.getpId();
 Map<String,id);
 map.put("name",name);
 map.put("pId",pId);
 Map<String,Object> map2 = this.digui(id,EwTreeVOs,map);
 menus.add(map2);
 }
 return menus;
 }
 
 /**
 * Purpose:遞迴父子關係
 * @author JaxWan
 * @param id 父節點id
 * @param EwTreeVOs2 選單集合
 * @param mapResult 結果集
 * @param lists 孩子集合
 * @return Map<String,Object>
 */
 public Map<String,Object> digui(String id,List<EwTreeVO> EwTreeVOs2,Map<String,Object> mapResult){
 List<Map<String,Object>> lists = new ArrayList<Map<String,Object>>();
 for (int j = 0; j < EwTreeVOs2.size(); j++) {
 EwTreeVO ewTreeVO2 = EwTreeVOs2.get(j);
 String id2 = ewTreeVO2.getId();
 String name2 = ewTreeVO2.getName();
 String pId2 = ewTreeVO2.getpId();
 if(id.equals(pId2)){
 Map<String,Object> map2 = new HashMap<String,Object>();
 map2.put("id",id2);
 map2.put("name",name2);
 map2.put("pId",pId2);
 lists.add(map2);
 EwTreeVOs2.remove(j);
 j--;
 }
 }
 mapResult.put("children",lists);
 for (int i = 0; i < lists.size(); i++) {
 Map<String,Object> tempMap = lists.get(i);
 String id1 = (String) tempMap.get("id");
 this.digui(id1,EwTreeVOs2,tempMap);
 }
 return mapResult;
 }

總結

以上所述是小編給大家介紹的vue+ java 實現多級選單遞迴效果，希望對大家有所幫助，如果大家有任何疑問請給我留言，小編會及時回覆大家的。在此也非常感謝大家對我們網站的支援！
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