<view class="container">
 <form catchsubmit="formSubmit">
  <view class="form-card">
   <view class="weui-cell weui-cell_input">
    <view class="weui-cell__hd">
     <view class="weui-label">物種<span>*</span></view>
    </view>
    <view class="weui-cell__bd">
     <picker mode="multiSelector" bindchange="bindMultiPickerChange" bindcolumnchange="bindMultiPickerColumnChange" value="{{multiIndex}}" range="{{multiArray}}">
      <view class="weui-input">{{multiArray[0][multiIndex[0]]}}{{multiArray[1][multiIndex[1]]}}{{multiArray[2][multiIndex[2]]}}</view>
     </picker>
    </view>
   </view>
  </view>
 </form>  
</view>

Page({
 
 /**
  * 頁面的初始數(shù)據
  */
 data: {
  objectMultiShow: [],
  objectMultiArray: [],
  multiArray: [],
  multiIndex: [],
  checkeIndex: []
 },
 
 /**
  * 生命周期函數(shù)--監(jiān)聽頁面加載
  * objectMultiShow--匹配多列選擇器渲染數(shù)據所對應的json數(shù)據（包含id，parentId，name）
  * multiArray--多列選擇器渲染數(shù)據
  */
 onLoad: function (options) {
  // 初始化
  let data = {
   objectMultiShow: this.data.objectMultiShow,
   objectMultiArray: this.data.objectMultiArray,
   multiArray: this.data.multiArray,
   multiIndex: this.data.multiIndex,
   checkeIndex: this.data.checkeIndex
  }
  data.objectMultiArray = [
   [{ id: 0, name: '無脊柱動物' }, { id: 1, name: '脊柱動物' }],
   [
    { id: 0, name: '扁性動物', parentId: 0 }, { id: 1, name: '線形動物', parentId: 0 }, { id: 2, name: '環(huán)節(jié)動物', parentId: 0 }, { id: 3, name: '軟體動物', parentId: 0 }, { id: 4, name: '節(jié)肢動物', parentId: 0 },
    { id: 5, name: '魚', parentId: 1 }, { id: 6, name: '兩棲動物', parentId: 1 }, { id: 7, name: '爬行動物', parentId: 1 }
   ],
   [
    { id: 0, name: '豬肉絳蟲', parentId: 0 }, { id: 1, name: '吸血蟲', parentId: 0 },
    { id: 2, name: '蛔蟲', parentId: 1 },
    { id: 3, name: '螞蟻', parentId: 2 }, { id: 4, name: '螞蟥', parentId: 2 },
    { id: 5, name: '河蚌', parentId: 3 }, { id: 6, name: '蝸牛', parentId: 3 }, { id: 7, name: '蛞蝓', parentId: 3 },
    { id: 8, name: '昆蟲', parentId: 4 }, { id: 9, name: '甲殼動物', parentId: 4 }, { id: 10, name: '蛛形動物', parentId: 4 }, { id: 11, name: '多足動物', parentId: 4 },
    { id: 3, name: '鯽魚', parentId: 5 }, { id: 4, name: '帶魚', parentId: 5 },
    { id: 3, name: '青蛙', parentId: 6 }, { id: 4, name: '娃娃魚', parentId: 6 },
    { id: 3, name: '蜥蜴', parentId: 7 }, { id: 4, name: '龜', parentId: 7 }, { id: 4, name: '壁虎', parentId: 7 },
   ]
  ]
  data.objectMultiShow = data.objectMultiArray.map((item, index) => {
   if (index > 0) {
    item = item.filter(i => i.parentId === data.objectMultiArray[index - 1][0].id)
   }
   return item
  })
  data.multiArray = data.objectMultiShow.map(item => {
   item = item.map(i => i.name)
   return item
  })
  console.log(data.multiIndex)
  // 數(shù)據更新
  this.setData(data)
 },
 
 bindMultiPickerChange: function (e) {
  console.log('picker發(fā)送選擇改變，攜帶值為', e.detail.value)
  this.setData({
   multiIndex: e.detail.value
  })
 },
 bindMultiPickerColumnChange: function (e) {
  console.log('修改的列為', e.detail.column, '，值為', e.detail.value);
  // 初始化數(shù)據
  var data = {
   objectMultiShow: this.data.objectMultiShow,
   multiArray: this.data.multiArray,
   multiIndex: this.data.multiIndex
  };
 
  // 改變第i列數(shù)據之后，后幾列選擇第0個選項（重置）
  data.multiIndex[e.detail.column] = e.detail.value;
  for (let i = e.detail.column; i < data.multiIndex.length - 1; i++) {
   data.multiIndex[i + 1] = 0
  }
 
  /**
   * 改變第i列數(shù)據之后，后幾列數(shù)據更新
   * 兩種寫法：for 和 switch，switch為三列選擇器寫法，for由switch精簡拓展過來，可用于多列選擇器
   * swich寫法：如果更改的是第一列數(shù)據，第二列數(shù)據通過filter篩選（parentId = 第一列選中項id），同時更新第三列數(shù)據
   *      如果更改的是第二列數(shù)據，更新第三列數(shù)據 通過filter篩選（parentId = 第二列選中項id）
   */
  let arry = this.data.objectMultiArray
  for (let i = e.detail.column; i < data.multiIndex.length - 1; i++) {
   data.objectMultiShow[i + 1] = arry[i + 1].filter(item => item.parentId === data.objectMultiShow[i][data.multiIndex[i]].id)
   data.multiArray[i + 1] = data.objectMultiShow[i + 1].map(item => item.name)
  }
  /*switch (e.detail.column) {
   case 0:
    data.objectMultiShow[1] = arry[1].filter(item => item.parentId === data.objectMultiShow[0][data.multiIndex[0]].id)
    data.multiArray[1] = data.objectMultiShow[1].map(item => item.name)
    data.objectMultiShow[2] = arry[2].filter(item => item.parentId === data.objectMultiShow[1][data.multiIndex[1]].id)
    data.multiArray[2] = data.objectMultiShow[2].map(item => item.name)
    break;
   case 1:
    data.objectMultiShow[2] = arry[2].filter(item => item.parentId === data.objectMultiShow[1][data.multiIndex[1]].id)
    data.multiArray[2] = data.objectMultiShow[2].map(item => item.name)
  }*/
  // 數(shù)據更新
  this.setData(data);
 }
})