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: 0;
}

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：