自定义指令v-loading，只需要绑定Boolean即可
v-loading=“loading”

<el-table :data="list" border style="width: 100%" v-loading="loading">
        <el-table-column align="center" label="序号" width="50">
        </el-table-column>
        <el-table-column align="center" prop="name" label="角色" width="200">
        </el-table-column>
        <el-table-column align="center" prop="state" label="启用" width="200">
          <template v-slot="{ row }">
            <span style="margin-left: 10px">
              {{
                row.state === 1 ? "已启用" : row.state === 0 ? "未启用" : "无"
              }}
            </span>
          </template>
        </el-table-column>
        <el-table-column align="center" prop="description" label="描述">
        </el-table-column>
        <el-table-column align="center" label="操作">
          <template>
            <el-button size="mini" type="text">分配权限</el-button>
            <el-button size="mini" type="text">编辑</el-button>
            <el-button size="mini" type="text">删除</el-button>
          </template>
        </el-table-column>
      </el-table>

loading: false,默认为false

export default {
  data() {
    return {
      loading: false, //默认加载为false
      }
   }，
    methods: {
    async getRoleList() {
     //刚进来开启loading加载
      this.loading = true;
      const { rows, total } = await getRoleList(this.pageParams);
      this.list = rows;
      this.pageParams.total = total;
      //等待接口获取到数据，关闭加载
      this.loading = false;
    },
  },
}