vant-weapp/packages/cascader/demo/index.wxml

<demo-block title="基础用法">
  <van-field
    value="{{ baseState.result }}"
    is-link
    readonly
    label="地区"
    placeholder="{{ selectArea }}"
    data-state-key="baseState"
    bind:tap="onClick"
  />
  <van-popup
    show="{{ baseState.show }}"
    round
    position="bottom"
  >
    <van-cascader
      wx:if="{{ baseState.show }}"
      value="{{ baseState.value }}"
      title="{{ selectArea }}"
      options="{{ options }}"
      data-state-key="baseState"
      bind:close="onClose"
      bind:finish="onFinish"
    />
  </van-popup>
</demo-block>

<demo-block title="自定义颜色">
  <van-field
    value="{{ customColorState.result }}"
    is-link
    readonly
    label="地区"
    placeholder="{{ selectArea }}"
    data-state-key="customColorState"
    bind:tap="onClick"
  />
  <van-popup
    show="{{ customColorState.show }}"
    round
    position="bottom"
  >
    <van-cascader
      wx:if="{{ customColorState.show }}"
      value="{{ customColorState.value }}"
      title="{{ selectArea }}"
      options="{{ options }}"
      data-state-key="customColorState"
      active-color="#ee0a24"
      bind:close="onClose"
      bind:finish="onFinish"
    />
  </van-popup>
</demo-block>

<demo-block title="异步加载选项">
  <van-field
    value="{{ asyncState.result }}"
    is-link
    readonly
    label="地区"
    placeholder="{{ selectArea }}"
    data-state-key="asyncState"
    bind:tap="onClick"
  />
  <van-popup
    show="{{ asyncState.show }}"
    round
    position="bottom"
  >
    <van-cascader
      wx:if="{{ asyncState.show }}"
      value="{{ asyncState.value }}"
      title="{{ selectArea }}"
      options="{{ asyncState.options }}"
      data-state-key="asyncState"
      bind:close="onClose"
      bind:change="loadDynamicOptions"
      bind:finish="onFinish"
    />
  </van-popup>
</demo-block>

<demo-block title="自定义字段名">
  <van-field
    value="{{ customFieldState.result }}"
    is-link
    readonly
    label="地区"
    placeholder="{{ selectArea }}"
    data-state-key="customFieldState"
    bind:tap="onClick"
  />
  <van-popup
    show="{{ customFieldState.show }}"
    round
    position="bottom"
    safe-area-inset-bottom
  >
    <van-cascader
      wx:if="{{ customFieldState.show }}"
      data-state-key="customFieldState"
      value="{{ customFieldState.value }}"
      title="{{ selectArea }}"
      options="{{ customFieldOptions }}"
      field-names="{{ fieldNames }}"
      data-state-key="customFieldState"
      bind:close="onClose"
      bind:finish="onFinish"
    />
  </van-popup>
</demo-block>