Vue中v-show添加表达式的问题(判断是否显示)

 infoTypeList: [
 {
  id: 11,
  name: '新闻',
  mark: 'news'
 },
 {
  id: 13,
  name: '论坛',
  mark: 'bbs'
 },
 {
  id: 17,
  name: '微博',
  mark: 'wb'
 },
 {
  id: 6,
  name: '微信',
  mark: 'wx'
 },
 {
  id: 7,
  name: 'APP',
  mark: 'app'
 },
 {
  id: 8,
  name: '平媒',
  mark: 'pm'
 },
 {
  id: 20,
  name: '境外',
  mark: 'overseas'
 },
 {
  id: 21,
  name: 'Facebook',
  mark: 'facebook'
 },
 {
  id: 22,
  name: 'Twitter',
  mark: 'twitter'
 }
],

markTypeList: [
{
id: 32,
name: '主帖',
mark: 'bbs'
},
{
id: 33,
name: '回帖',
mark: 'bbs'
},
{
id: 34,
name: '原创',
mark: 'wb'
},
{
id: 35,
name: '转发',
mark: 'wb_wx'
},
{
id: 36,
name: '头条',
mark: 'news_app_wx_pm'
},
{
id: 37,
name: '头图',
mark: 'app'
},
{
id: 38,
name: '置顶',
mark: 'app'
},
{
id: 39,
name: '要闻',
mark: 'news'
},
{
id: 40,
name: '头版',
mark: 'pm'
},
],

<div v-if="isShowSingleInfoType">
<label class="left-10">数据来源</label>
<span class="info-type activecolor" @click="changeInfoType(-1)">全部</span>
<span class="info-type" @click="changeInfoType(item.id, item.mark)" v-for="item in infoTypeList" :key="item.id">{{item.name}}</span>
<label class="multichoose">
<Button @click="toggleInfoType" size="small">+多选</Button>
</label>
</div>

<div class="layout-content-main">
<label class="left-10">

</label>
<span class="mark-type activecolor" @click="changeMarkType(-1)">全部</span>
<span v-show="item.mark.indexOf(infoTypeMark) > -1" class="mark-type" @click="changeMarkType(item.id)" v-for="item in markTypeList" :key="item.id">{{item.name}}</span>
</div>