本期的微信小程序实战篇来做一个电商网站经常用到的-商品属性联动选择的效果，素材参考了一点点奶茶。 **效果演示：

代码示例

1、commodity.xml

 
<!-- <view class="title">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-code="{{attrCode}}" 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" bindtap="submit">选好了       </button> 
</view>

上述代码把页面盒子分为两部分commodity_attr_list和weui-btn-area。 commodity_attr_list：循环获取商品的属性名和相对应的属性值，并布局页面。 weui-btn-area：提交校验并获取选中商品属性结果。

2、commodity.js

数据结构

    //数据结构：以一组一组的数据来进行设定 
    commodityAttr: [
      {
        priceId: 1,
        price: 35.0,
        "stock": 8,
        "attrValueList": [
          {
            "attrKey": "规格：",
            "attrValue": "+免费配料",
            "attrCode": "1001"
          },
          {
            "attrKey": "甜度：",
            "attrValue": "七分甜",
            "attrCode": "2001"
          },
          {
            "attrKey": "加料：",
            "attrValue": "珍珠",
            "attrCode": "3001"
          },
          {
            "attrKey": "冰块：",
            "attrValue": "少冰",
            "attrCode": "4001"
          }
        ]
      },
      {
        priceId: 2,
        price: 35.1,
        "stock": 9,
        "attrValueList": [
          {
            "attrKey": "规格：",
            "attrValue": "+燕麦",
            "attrCode": "1002"
          },
          {
            "attrKey": "甜度：",
            "attrValue": "五分甜",
            "attrCode": "2002"
          },
          {
            "attrKey": "加料：",
            "attrValue": "椰果",
            "attrCode": "3002"
          },
          {
            "attrKey": "冰块：",
            "attrValue": "去冰",
            "attrCode": "4002"
          }
        ]
      },
      {
        priceId: 3,
        price: 35.2,
        "stock": 10,
        "attrValueList": [
          {
            "attrKey": "规格：",
            "attrValue": "+布丁",
            "attrCode": "1003"
          },
          {
            "attrKey": "甜度：",
            "attrValue": "无糖",
            "attrCode": "2003"
          },
          {
            "attrKey": "加料：",
            "attrValue": "仙草",
            "attrCode": "3003"
          },
          {
            "attrKey": "冰块：",
            "attrValue": "常温",
            "attrCode": "4003"
          }
        ]
      },
      {
        priceId: 4,
        price: 35.2,
        "stock": 10,
        "attrValueList": [
          {
            "attrKey": "规格：",
            "attrValue": "再加一份奶霜",
            "attrCode": "1004"
          },
          {
            "attrKey": "甜度：",
            "attrValue": "无糖",
            "attrCode": "2003"
          },
          {
            "attrKey": "加料：",
            "attrValue": "仙草",
            "attrCode": "3004"
          },
          {
            "attrKey": "冰块：",
            "attrValue": "热饮",
            "attrCode": "4004"
          }
        ]
      },
      {
        priceId: 5,
        price: 35.2,
        "stock": 10,
        "attrValueList": [
          {
            "attrKey": "规格：",
            "attrValue": "+免费配料",
            "attrCode": "1004"
          },
          {
            "attrKey": "甜度：",
            "attrValue": "五分甜",
            "attrCode": "2003"
          },
          {
            "attrKey": "加料：",
            "attrValue": "椰果",
            "attrCode": "3004"
          },
          {
            "attrKey": "冰块：",
            "attrValue": "常温",
            "attrCode": "4004"
          }
        ]
      }
    ],
    attrValueList: []
  }

属性选中和取消选择效果处理

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);
      }
    }
  }

结果提交

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: '请选择完整！',
        icon: 'loading',
        duration: 1000
      })
    } else {
      var valueStr = "";
      for(var i = 0;i < value.length;i++){
        console.log(value[i]);
        valueStr += value[i]+",";
      }
      wx.showModal({
        title: '提示',
        content: valueStr,
        success: function (res) {
          if (res.confirm) {
            console.log('用户点击确定')
          } else if (res.cancel) {
            console.log('用户点击取消')
          }
        }
      })  
      console.log(valueStr);
    }
  }

3、commodity.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; 
 display: flex;
 flex-direction: column;
} 
/*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 30rpx; 
 margin: 10rpx 10rpx; 
 border: 1rpx solid #ececec; 
 border-radius:5px;
 line-height:30px;
} 
/*每个属性选中的当前样式*/
.attr_value_active { 
 border-radius: 10rpx; 
 color: #0089dc; 
 padding: 0 30rpx; 
 border: 1rpx solid #0089dc; 
 /* background: #fff;   */
} 
/*禁用属性*/
.attr_value_disabled { 
 color: #ccc; 
} 
  
/*button*/
.weui-btn-area { 
 margin: 1.17647059em 15px 0.3em; 
} 
.weui-btn{
  width: 80%;
  height: 100rpx;
  border-radius: 3rpx; 
  background-color:#0089dc; 
  color: #fff; 
}

好了，复制上述代码就可以实现效果哦，赶紧试试吧！

更多精彩内容

微信小程序实战篇：基于wxcharts.js绘制移动报表

####关注我们如果需要源码可以关注“IT实战联盟”公众号并留言（源码名称+邮箱），小萌看到后会联系作者发送到邮箱，也可以加入交流群和作者互撩哦~~~