Vue如何使得导航栏文字光标如何与内容同步

效果演示：
当我们点击上方链接的时候，这个光标会随着我们的点击，在不同的地方发生变化。

项目结构
这是一个标准的vue项目的结构。

完整代码：
这个是上方导航栏的组件代码。
NavBar.vue

<template>
    <nav class="navbar navbar-expand-lg navbar-dark bg-dark">
  <div class="container">
    <router-link class="navbar-brand" :to="{name: 'home'}">King Of Bots</router-link>
    <div class="collapse navbar-collapse" id="navbarText">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">          
          <router-link :class="route_name == 'pk_index' ? 'nav-link active' : 'nav-link' " :to="{name: 'pk_index'}">对战</router-link>
        </li>
        <li class="nav-item">
          <router-link :class="route_name == 'record_index' ? 'nav-link active' : 'nav-link' " :to="{name: 'record_index'}">对局列表</router-link>
        </li>
        <li class="nav-item">
          <router-link :class="route_name == 'ranklist_index' ? 'nav-link active' : 'nav-link' " :to="{name: 'ranklist_index'}">排行榜</router-link>          
        </li>
      </ul>
      <ul class="navbar-nav">
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown" aria-expanded="false">
            极客李华
        </a>
          <ul class="dropdown-menu">
            <router-link class="dropdown-item" :to="{name: 'user_bot_index'}">我的Bot</router-link>
            <li>              
              <hr class="dropdown-divider">
            </li>
            <li><a class="dropdown-item" href="#">退出</a></li>
            
          </ul>
        </li>
      </ul>
    </div>
  </div>
</nav>
</template>

<script>
import {useRoute} from 'vue-router'
import {computed} from 'vue'

export default{
  setup(){
    const route = useRoute();
    // computed可以计算当前的route是哪个 并返回它的名字
    let route_name = computed(() => route.name)
    return {
      route_name
    }
  }
}
</script>
<style>

</style>

index.js

import { createRouter, createWebHistory } from 'vue-router'
import PkIndexView from '../views/pk/PkIndexView'
import RecordindexView from '../views/record/RecordindexView'
import RanklistindexView from '../views/ranklist/RanklistindexView'
import UserBotindexView from '../views/user/bot/UserBotindexView'
import NotFound from '../views/error/NotFound'


const routes = [
  {
    path: "/",
    name: "home",
    redirect: "/pk/"
  },
  {
    path: "/pk/",
    name: "pk_index",
    component: PkIndexView,
  },
  {
    path: "/record/",
    name: "record_index",
    component: RecordindexView,
  },
  {
    path: "/ranklist/",
    name: "ranklist_index",
    component: RanklistindexView,
  },
  {
    path: "/user/bot/",
    name: "user_bot_index",
    component: UserBotindexView,
  },
  {
    path: "/404/",
    name: "404",
    component: NotFound,
  },
  {
    path: "/:catchAll(.*)",
    redirect: "/404/"
  },
]

const router = createRouter({
  history: createWebHistory(),
  routes
})

export default router

提取代码讲解

computed函数可以时时的获取当前的route的名字，具体写法就是下面的样子，然后返回每次的route的名字。

<script>
import {useRoute} from 'vue-router'
import {computed} from 'vue'

export default{
  setup(){
    const route = useRoute();
    // computed可以计算当前的route是哪个 并返回它的名字
    let route_name = computed(() => route.name)
    return {
      route_name
    }
  }
}
</script>
<style>

让这里的三元表达式获取到之后，进行判断，然后如果当前的这个标签是当前网页在运行的，那么就让这个样式里面再加上的一个active。

<router-link :class="route_name == 'pk_index' ? 'nav-link active' : 'nav-link' " :to="{name: 'pk_index'}">对战</router-link>