<div class="content-box">
      <span v-for="(item,index) in classListChan" :key="index" :class="[{active: checkedGroup.indexOf(index) > -1},'class-item']" @click="changeStyle(index)">{{item.className}}</span>
    </div>

    data () {
      return {
        checkedGroup: [],
        classListChan:[],
      }
    },
      //切换班级样式
      changeStyle(index) {
        if(this.checkedGroup.indexOf(index) == -1) {
          this.checkedGroup.push(index);
        }else {
          var spliceIndex = this.checkedGroup.indexOf(index);
          this.checkedGroup.splice(spliceIndex, 1);
        }
      },