"usingComponents": {
  "van-popup": "@vant/weapp/popup/index"
}

<van-cell title="展示弹出层" is-link bind:click="showPopup" />

<van-popup show="{{ show }}" bind:close="onClose">内容</van-popup>

Page({
  data: {
    show: false,
  },

  showPopup() {
    this.setData({ show: true });
  },

  onClose() {
    this.setData({ show: false });
  },
});

<van-popup
  show="{{ show }}"
  position="top"
  custom-style="height: 20%;"
  bind:close="onClose"
/>

<van-popup
  show="{{ show }}"
  closeable
  position="bottom"
  custom-style="height: 20%"
  bind:close="onClose"
/>

<!-- 自定义图标 -->
<van-popup
  show="{{ show }}"
  closeable
  close-icon="close"
  position="bottom"
  custom-style="height: 20%"
  bind:close="onClose"
/>

<!-- 图标位置 -->
<van-popup
  show="{{ show }}"
  closeable
  close-icon-position="top-left"
  position="bottom"
  custom-style="height: 20%"
  bind:close="onClose"
/>

<van-popup
  show="{{ show }}"
  round
  position="bottom"
  custom-style="height: 20%"
  bind:close="onClose"
/>

<!-- page-meta 只能是页面内的第一个节点 -->
<page-meta page-style="{{ show ? 'overflow: hidden;' : '' }}" />

<van-popup show="{{ show }}" catch:touchstart />