answer-mini/wechat-app/static/vant/picker/index.wxml

<import src="./toolbar.wxml" />

<view class="van-picker custom-class">
  <template is="toolbar" wx:if="{{ toolbarPosition === 'top' }}" data="{{ showToolbar, cancelButtonText, title, confirmButtonText }}"></template>
  <view wx:if="{{ loading }}" class="van-picker__loading">
    <loading color="#1989fa"/>
  </view>
  <view
    class="van-picker__columns"
    style="height: {{ itemHeight * visibleItemCount }}px"
    catch:touchmove="noop"
  >
    <picker-column
      class="van-picker__column"
      wx:for="{{ isSimple(columns) ? [columns] : columns }}"
      wx:key="index"
      data-index="{{ index }}"
      custom-class="column-class"
      value-key="{{ valueKey }}"
      initial-options="{{ isSimple(columns) ? item : item.values }}"
      default-index="{{ item.defaultIndex || defaultIndex }}"
      item-height="{{ itemHeight }}"
      visible-item-count="{{ visibleItemCount }}"
      active-class="active-class"
      bind:change="onChange"
    />
    <view class="van-picker__mask" style="background-size: 100% {{ (itemHeight * visibleItemCount - itemHeight) / 2 }}px" />
    <view
      class="van-picker__frame van-hairline--top-bottom"
      style="height: {{ itemHeight }}px"
    />
  </view>
  <template is="toolbar" wx:if="{{ toolbarPosition === 'bottom' }}" data="{{ showToolbar, cancelButtonText, title, confirmButtonText }}"></template>
</view>

<wxs module="isSimple">
  function isSimple(columns) {
    return columns.length && !columns[0].values;
  }
  module.exports = isSimple;
</wxs>