解决Vue父路由进入子路由选中样式消失的问题

废话不多说，先展示有问题效果图，看是否和我的情况一样：

展示我的代码：我只是展示一下我的思路，有问题可以@我

路由部分

 {
      path:"/",//访问路径
      name:'Home',//路由名称
      component:()=>import ("@/views/Home")  //访问对应组件 ,动态导入组件，传统的导入组件，造成内存资源浪费  
    },
    {
      path:"/ClassRoom",
      name:'classroom',
      component:()=>import ("@/views/ClassRoom"),
      //redirect:'/ClassRoom/Learing',
      children:[
        {
          path:"/",
          name:'learing',
          component:()=>import ("@/components/ClassRoom/Course/Learing"),
        },
        {
          path:"/ClassRoom/Endlearing",
          name:'endlearing',
          component:()=>import ("@/components/ClassRoom/Course/Endlearing"),
        }
      ]          
    },
   
    {
      path:"/OpenCourses",
      name:'opencourses',
      component:()=>import ("@/views/OpenCourses") 
    },

    {
      path:"/Resources",
      name:'resources',
      component:()=>import ("@/views/Resources")
    },
    {
      path:"/Resources/ResourcesDetail",
      name:'resourcesdetail',
      component:()=>import ("@/components/ResourcesDetail")
    },
    {
      path:"/OpenResourcesDetail",
      name:'openresourcesdetail',
      component:()=>import ("@/components/OpenCLass/ResourcesDetail")
    
    },

<ul class="headerNav">
                 <li id="li-action" v-for="(item,index) in headlist" :key="index">
                     <router-link :to="{name:item.url}">{{item.head}}</router-link>
                     <!-- <span :class="{active_span:isChecked == index}"></span> -->
                 </li>
            
 </ul>

data() {
      return {
          headlist:[
              {id:1,head:'首页',url:"Home"},
              {id:2,head:'学习中心',url:"classroom"},
              {id:3,head:'视频资源',url:"resources"},
              {id:4,head:'公开课',url:"opencourses"}
          ],
          isChecked:0,
          isLocalUser:null//判断本地是否有用户名
      }
   },
/* 标题选中的样式 */
.headerNav li .router-link-exact-active{
    font-size: 22px !important;
    font-weight:bold !important;
    color: #347ABB !important;
    border-bottom: 5px solid #0059c5;
    box-sizing: border-box;
}

解决问题后的效果：

展示我的代码

<ul class="headerNav">
                  <!-- 单独把首页写了一行加了一个属性exact，让默认false，不然你选中别的标题，首页会一直选中，注意，上一份是写在data里面，直接遍历的 -->
                  <li id="li-action">
                       <router-link :to="{name:'Home'}" exact>首页</router-link>
                  </li>
                 <li id="li-action" v-for="(item,index) in headlist" :key="index">
                     <router-link :to="{name:item.url}">{{item.head}}</router-link>
                     <!-- <span :class="{active_span:isChecked == index}"></span> -->
                 </li>
            
              </ul>

headlist:[
              {id:1,head:'学习中心',url:"classroom"},
              {id:2,head:'视频资源',url:"resources"},
              {id:3,head:'公开课',url:"opencourses"}
          ],

/* 标题选中的样式  类名改变了，注意看*/
.headerNav li .router-link-active{
    font-size: 22px !important;
    font-weight:bold !important;
    color: #347ABB !important;
    border-bottom: 5px solid #0059c5;
    box-sizing: border-box;
}

如果我解释的不清楚，请参考：https://www.cnblogs.com/lisiyang/p/7867544.html