点击铃铛显示如下消息框：

如果点击消息，可以实现消息从列表中移除,并从铃铛总数上进行扣减对应的已读消息数。

关于以上功能的实现方式：

 <!-- 铃铛位置 -->
          <i class="el-icon-bell" @click="showPopover = true">
            <span class="badge" v-if="notificationCount <= 99">{{ notificationCount }}</span>
            <span class="badge" v-else>99+</span>
          </i>

          <!-- 列表框 -->
          <!-- 虚化背景 -->
          <div v-if="showPopover" class="popover" @click="closePopover"></div>
            <div v-if="showPopover" class="popover-content">
              <!-- class="close-button"-->
              <el-button class="close-button" size="mini" @click="showPopover = false">&times;</el-button>
              <div style="line-height: 20px;">您的消息</div>
              <ul class="notification-list">
                <li v-for="item in notifications" :key="item.id" class="notification-item">
                  <div @click="clickLink(item)">

                      <span>
                        <b>{{ item.title }}</b>:


                          <el-tooltip :content ="item.content" effect="dark" placement="top-start">
                            <span>{{ getTruncatedContent(item.content) }}</span>
                          </el-tooltip>

                        </span>
                    </div>
                </li>
              </ul>
            </div>
          </div>

export default {
  name: "xxx",
  data() {
    return {
	  notificationCount: 99, // 初始化消息数量为0
      showPopover: false,//展示列表框
      notifications:[
        {
          id:1,
          title:"订单完成通知",
          content:"您好，您的DD234825205已经完成了，点击查看相关信息"
        },
        {
          id:2,
          title:"工单完成通知",
          content:"您好，您的GD93453872已经完成了，点击查看相关信息"
        },
        {
          id:3,
          title:"货物入库通知",
          content:"您好，入库流水号为3247942582，成功入库，点击查看详情"
        },
        {
          id:4,
          title:"订单完成通知",
          content:"您好，您的DD292342485已经完成了，点击查看相关信息"
        },
        {
          id:5,
          title:"发货通知",
          content:"您好，您的发货单#3358347520已经开始发货，点击查看详情"
        },
        {
          id:6,
          title:"物料出库通知",
          content:"您好，您的物料编号233847587528出库成功，点击查看详情"
        },
        {
          id:7,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
        {
          id:8,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
        {
          id:9,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
        {
          id:10,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
        {
          id:11,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
        {
          id:12,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
        {
          id:13,
          title:"miaow1",
          content:"xxxxxxxxxx"
        },
      ]
 	};
 },


//用来检测文本内容长度
  computed: {
    getTruncatedContent() {
      return (content) => {
        if (content.length > 8) {
          return content.slice(0, 8) + '...';
        }
        return content;
      };
    },
  },


methods ：

	closePopover() {
      this.showPopover = false;
    },
    clickLink(notification){
      const index = this.notifications.indexOf(notification);
      if(index != -1){
        //在此获得相关路径，在用户点击相关信息的时候跳转链接
        //this.$router.push({path:"{{path}}"})
        this.notifications.splice(index,1);
      }
      if(this.notificationCount > 0){
        this.notificationCount --;
      }
      //然后跳转
    }

.bell-icon {
    position: relative;
    display: inline-block;
  }
.badge {
    // position: absolute;
    top: 100px;
    line-height:12px;
    right: 210px;
    background-color: white;
    color: red;
    border-radius: 50%;
    padding: 4px;
    font-size: 12px;
  }

.popover {
  position: fixed;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  background-color: rgba(0, 0, 0, 0.5);
  z-index: 999;
}

.popover-content {
  position: fixed;
  top: 56px;
  right: 120px;
  min-width: 220px;
  width: auto;
  max-height: 400px;
  background-color: white;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
  border-radius: 4px;
  padding: 10px;
  z-index: 1000;
  overflow-y: auto;
}

.notification-list {
  list-style: none;
  // padding: 0;
  font-size:15px;
  margin: 0;
  padding:0px;
  line-height:30px;

}

.notification-item {
  margin-bottom: 0px;
}

.notification-item h3 {
  margin: 0;
  font-size: 12px;
}

.notification-item p {
  margin: 0;
  font-size: 12px;
  color: #888;
}
.notification-item b {
  margin: 0;
  font-size: 13px;
  //我在想要不要将消息进行区分，比如绿色代表成功，橙色代表警告，红色代表错误
  color: green;
}
.notification-item span {
  margin: 0;
  font-size: 12px;
}

.close-button {
  position: absolute;
  top: 5px;
  right: 5px;
  border: none;
  background: none;
  font-size: 18px;
  // cursor: pointer;
}