微信小程序之商品属性分类

所提及的购物数量的加减，现在说说商品属性值联动选择。

为了让同学们有个直观的了解，到电商网截了一个图片，就是红圈所示的部分

现在就为大家介绍这个小组件，在小程序中，该如何去写

下图为本项目的图：

wxml：

 <view class="title">商品属性值联动选择</view>
 <!--options-->
 <view class="commodity_attr_list">
   <!--每组属性-->
   <view class="attr_box" wx:for="{{attrValueList}}" wx:for-item="attrValueObj" wx:for-index="attrIndex">
     <!--属性名-->
     <view class="attr_name">{{attrValueObj.attrKey}}</view>
     <!--属性值-->
     <view class="attr_value_box">
       <!--每个属性值-->
       <view class="attr_value {{attrIndex==firstIndex || attrValueObj.attrValueStatus[valueIndex]?(value==attrValueObj.selectedValue?'attr_value_active':''):'attr_value_disabled'}}" bindtap="selectAttrValue" data-status="{{attrValueObj.attrValueStatus[valueIndex]}}"
       data-value="{{value}}" data-key="{{attrValueObj.attrKey}}" data-index="{{attrIndex}}" data-selectedvalue="{{attrValueObj.selectedValue}}" wx:for="{{attrValueObj.attrValues}}" wx:for-item="value" wx:for-index="valueIndex">{{value}}</view>
     </view>
   </view>
 </view>
 <!--button-->
 <view class="weui-btn-area">
   <button class="weui-btn" type="primary" bindtap="submit">确定</button>
 </view>

wxss：

 .title {
   padding: 10rpx 20rpx;
   margin: 10rpx 0;
   border-left: 4rpx solid #ccc;
 }

 /*全部属性的主盒子*/
 .commodity_attr_list {
   background: #fff;
   padding: 0 20rpx;
   font-size: 26rpx;
   overflow: hidden;
   width: 100%;
 }
 /*每组属性的主盒子*/
 .attr_box {
   width: 100%;
   overflow: hidden;
   border-bottom: 1rpx solid #ececec;
 }
 /*属性名*/
 .attr_name {
   width: 20%;
   float: left;
   padding: 15rpx 0;
 }
 /*属性值*/
 .attr_value_box {
   width: 80%;
   float: left;
   padding: 15rpx 0;
   overflow: hidden;
 }
 /*每个属性值*/
 .attr_value {
   float: left;
   padding: 0 10rpx;
   margin: 0 10rpx;
   border: 1rpx solid #ececec;
 }
 /*每个属性选中的当前样式*/
 .attr_value_active {
   background: #FFCC00;
   border-radius: 10rpx;
   color: #fff;
   padding: 0 10rpx;
 }
 /*禁用属性*/
 .attr_value_disabled {
   color: #ccc;
 }

 /*button*/
 .btn-area {
   margin: 1.17647059em 15px 0.3em;
 }

 .btn {
   margin-top: 15px;
   background-color:#FFCC00;
   color: #fff;
 }
 .btn:first-child {
   margin-top:;
 }

js：

数据部分，一般情况都是访问接口获取数据的，这里并没有使用网络访问，为了简化demo，直接把一组数据放在data对象中。

 Page({
   data: {
     firstIndex: -1,
     //准备数据
     //数据结构：以一组一组来进行设定
     commodityAttr: [
       {
         priceId: 1,
         price: 35.0,
         "stock": 8,
         "attrValueList": [
           {
             "attrKey": "型号",
             "attrValue": "2"
           },
           {
             "attrKey": "颜色",
             "attrValue": "白色"
           },
           {
             "attrKey": "大小",
             "attrValue": "小"
           },
           {
             "attrKey": "尺寸",
             "attrValue": "S"
           }
         ]
       },
       {
         priceId: 2,
         price: 35.1,
         "stock": 9,
         "attrValueList": [
           {
             "attrKey": "型号",
             "attrValue": "1"
           },
           {
             "attrKey": "颜色",
             "attrValue": "黑色"
           },
           {
             "attrKey": "大小",
             "attrValue": "小"
           },
           {
             "attrKey": "尺寸",
             "attrValue": "M"
           }
         ]
       },
       {
         priceId: 3,
         price: 35.2,
         "stock": 10,
         "attrValueList": [
           {
             "attrKey": "型号",
             "attrValue": "1"
           },
           {
             "attrKey": "颜色",
             "attrValue": "绿色"
           },
           {
             "attrKey": "大小",
             "attrValue": "大"
           },
           {
             "attrKey": "尺寸",
             "attrValue": "L"
           }
         ]
       },
       {
         priceId: 4,
         price: 35.2,
         "stock": 10,
         "attrValueList": [
           {
             "attrKey": "型号",
             "attrValue": "1"
           },
           {
             "attrKey": "颜色",
             "attrValue": "绿色"
           },
           {
             "attrKey": "大小",
             "attrValue": "大"
           },
           {
             "attrKey": "尺寸",
             "attrValue": "L"
           }
         ]
       }
     ],
     attrValueList: []
   },
   onShow: function () {
     this.setData({
       includeGroup: this.data.commodityAttr
     });
     this.distachAttrValue(this.data.commodityAttr);
     // 只有一个属性组合的时候默认选中
     // console.log(this.data.attrValueList);
     if (this.data.commodityAttr.length == 1) {
       for (var i = 0; i < this.data.commodityAttr[0].attrValueList.length; i++) {
         this.data.attrValueList[i].selectedValue = this.data.commodityAttr[0].attrValueList[i].attrValue;
       }
       this.setData({
         attrValueList: this.data.attrValueList
       });
     }
   },
   /* 获取数据 */
   distachAttrValue: function (commodityAttr) {
     /**
       将后台返回的数据组合成类似
       {
         attrKey:'型号',
         attrValueList:['1','2','3']
       }
     */
     // 把数据对象的数据（视图使用），写到局部内
     var attrValueList = this.data.attrValueList;
     // 遍历获取的数据
     for (var i = 0; i < commodityAttr.length; i++) {
       for (var j = 0; j < commodityAttr[i].attrValueList.length; j++) {
         var attrIndex = this.getAttrIndex(commodityAttr[i].attrValueList[j].attrKey, attrValueList);
         // console.log('属性索引', attrIndex);
         // 如果还没有属性索引为-1，此时新增属性并设置属性值数组的第一个值；索引大于等于0，表示已存在的属性名的位置
         if (attrIndex >= 0) {
           // 如果属性值数组中没有该值，push新值；否则不处理
           if (!this.isValueExist(commodityAttr[i].attrValueList[j].attrValue, attrValueList[attrIndex].attrValues)) {
             attrValueList[attrIndex].attrValues.push(commodityAttr[i].attrValueList[j].attrValue);
           }
         } else {
           attrValueList.push({
             attrKey: commodityAttr[i].attrValueList[j].attrKey,
             attrValues: [commodityAttr[i].attrValueList[j].attrValue]
           });
         }
       }
     }
     // console.log('result', attrValueList)
     for (var i = 0; i < attrValueList.length; i++) {
       for (var j = 0; j < attrValueList[i].attrValues.length; j++) {
         if (attrValueList[i].attrValueStatus) {
           attrValueList[i].attrValueStatus[j] = true;
         } else {
           attrValueList[i].attrValueStatus = [];
           attrValueList[i].attrValueStatus[j] = true;
         }
       }
     }
     this.setData({
       attrValueList: attrValueList
     });
   },
   getAttrIndex: function (attrName, attrValueList) {
     // 判断数组中的attrKey是否有该属性值
     for (var i = 0; i < attrValueList.length; i++) {
       if (attrName == attrValueList[i].attrKey) {
         break;
       }
     }
     return i < attrValueList.length ? i : -1;
   },
   isValueExist: function (value, valueArr) {
     // 判断是否已有属性值
     for (var i = 0; i < valueArr.length; i++) {
       if (valueArr[i] == value) {
         break;
       }
     }
     return i < valueArr.length;
   },
   /* 选择属性值事件 */
   selectAttrValue: function (e) {
     /*
     点选属性值，联动判断其他属性值是否可选
     {
       attrKey:'型号',
       attrValueList:['1','2','3'],
       selectedValue:'1',
       attrValueStatus:[true,true,true]
     }
     console.log(e.currentTarget.dataset);
     */
     var attrValueList = this.data.attrValueList;
     var index = e.currentTarget.dataset.index;//属性索引
     var key = e.currentTarget.dataset.key;
     var value = e.currentTarget.dataset.value;
     if (e.currentTarget.dataset.status || index == this.data.firstIndex) {
       if (e.currentTarget.dataset.selectedvalue == e.currentTarget.dataset.value) {
         // 取消选中
         this.disSelectValue(attrValueList, index, key, value);
       } else {
         // 选中
         this.selectValue(attrValueList, index, key, value);
       }

     }
   },
   /* 选中 */
   selectValue: function (attrValueList, index, key, value, unselectStatus) {
     // console.log('firstIndex', this.data.firstIndex);
     var includeGroup = [];
     if (index == this.data.firstIndex && !unselectStatus) { // 如果是第一个选中的属性值，则该属性所有值可选
       var commodityAttr = this.data.commodityAttr;
       // 其他选中的属性值全都置空
       // console.log('其他选中的属性值全都置空', index, this.data.firstIndex, !unselectStatus);
       for (var i = 0; i < attrValueList.length; i++) {
         for (var j = 0; j < attrValueList[i].attrValues.length; j++) {
           attrValueList[i].selectedValue = '';
         }
       }
     } else {
       var commodityAttr = this.data.includeGroup;
     }

     // console.log('选中', commodityAttr, index, key, value);
     for (var i = 0; i < commodityAttr.length; i++) {
       for (var j = 0; j < commodityAttr[i].attrValueList.length; j++) {
         if (commodityAttr[i].attrValueList[j].attrKey == key && commodityAttr[i].attrValueList[j].attrValue == value) {
           includeGroup.push(commodityAttr[i]);
         }
       }
     }
     attrValueList[index].selectedValue = value;

     // 判断属性是否可选
     for (var i = 0; i < attrValueList.length; i++) {
       for (var j = 0; j < attrValueList[i].attrValues.length; j++) {
         attrValueList[i].attrValueStatus[j] = false;
       }
     }
     for (var k = 0; k < attrValueList.length; k++) {
       for (var i = 0; i < includeGroup.length; i++) {
         for (var j = 0; j < includeGroup[i].attrValueList.length; j++) {
           if (attrValueList[k].attrKey == includeGroup[i].attrValueList[j].attrKey) {
             for (var m = 0; m < attrValueList[k].attrValues.length; m++) {
               if (attrValueList[k].attrValues[m] == includeGroup[i].attrValueList[j].attrValue) {
                 attrValueList[k].attrValueStatus[m] = true;
               }
             }
           }
         }
       }
     }
     // console.log('结果', attrValueList);
     this.setData({
       attrValueList: attrValueList,
       includeGroup: includeGroup
     });

     var count = 0;
     for (var i = 0; i < attrValueList.length; i++) {
       for (var j = 0; j < attrValueList[i].attrValues.length; j++) {
         if (attrValueList[i].selectedValue) {
           count++;
           break;
         }
       }
     }
     if (count < 2) {// 第一次选中，同属性的值都可选
       this.setData({
         firstIndex: index
       });
     } else {
       this.setData({
         firstIndex: -1
       });
     }
   },
   /* 取消选中 */
   disSelectValue: function (attrValueList, index, key, value) {
     var commodityAttr = this.data.commodityAttr;
     attrValueList[index].selectedValue = '';

     // 判断属性是否可选
     for (var i = 0; i < attrValueList.length; i++) {
       for (var j = 0; j < attrValueList[i].attrValues.length; j++) {
         attrValueList[i].attrValueStatus[j] = true;
       }
     }
     this.setData({
       includeGroup: commodityAttr,
       attrValueList: attrValueList
     });

     for (var i = 0; i < attrValueList.length; i++) {
       if (attrValueList[i].selectedValue) {
         this.selectValue(attrValueList, i, attrValueList[i].attrKey, attrValueList[i].selectedValue, true);
       }
     }
   },
   /* 点击确定 */
   submit: function () {
     var value = [];
     for (var i = 0; i < this.data.attrValueList.length; i++) {
       if (!this.data.attrValueList[i].selectedValue) {
         break;
       }
       value.push(this.data.attrValueList[i].selectedValue);
     }
     if (i < this.data.attrValueList.length) {
       wx.showToast({
         title: '请完善属性',
         icon: 'loading',
         duration: 1000
       })
     } else {
       wx.showToast({
         title: '选择的属性：' + value.join('-'),
         icon: 'sucess',
         duration: 1000
       })
     }
   }
 })

运行效果：