vue 點擊添加class，其他元素移除class（循環數組）

<div class="admin-main-nav">
      <ul id="mainNav">
        <li
          v-for="(item, index) in items"
          :key="item.id"
          :class="{ active: current == index }"
          @click="selectNav(index)"
        >
          <span><i :class="item.icon"></i></span>
          <a href="###">{{ item.title }}</a>
        </li>
      </ul>
    </div>

export default {
  data() {
    return {
      current: 0,
      items: [
        {
          title: "首頁",
          icon: "icon-menu01",
          id: 1
        },
        {
          title: "工作",
          icon: "icon-menu02",
          id: 2
        },
        {
          title: "呼叫",
          icon: "icon-menu03",
          id: 3
        },
        {
          title: "任務",
          icon: "icon-menu04",
          id: 4
        },
        {
          title: "學習",
          icon: "icon-menu05",
          id: 5
        }
      ]
    };
  },
  methods: {
    selectNav: function(index) {
      this.current = index;
    }
  }
};