京东小程序自定义select下拉框

问题描述：由于小程序没有自带的select下拉框，所以自定义了个公共组件

效果展示：

　　

1、在与page同级的component下新建一个select文件夹

　　select.jxml

<view class='ms-content-box'>
  <view class='ms-content' bindtap='selectToggle'>
    <view class='ms-text'>{{selectText}}</view>
    <view class="{{selectShow ? 'icon-up' : 'icon-down'}}"></view>
  </view>
  <view class='ms-options' jd:if="{{selectShow}}">
    <view jd:for="{{propArray}}" data-index="{{index}}" jd:key='index' class='ms-option' bindtap='setText'>{{item.name || item.value || item}}</view>
  </view>
</view>

　　select.jxss

.ms-content-box {
  width: 320rpx;
}

.ms-content {
  border: 1px solid #e2e2e2;
  background: white;
  font-size: 16px;
  position: relative;
  height: 56rpx;
  line-height: 56rpx;
  border-radius: 6rpx;
  color: #9e9e9e;
  padding: 6rpx 6rpx ;
  margin-bottom: 6rpx;
}

.ms-text {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  padding: 0 40px 0 6px;
  font-size: 14px;
}

.ms-options {
  background: white;
  width: inherit;
  position: absolute;
  border: 1px solid #e2e2e2;
  border-top: none;
  box-sizing: border-box;
  z-index: 3;
  min-height: 62rpx;
  overflow: auto;
  max-height: 380rpx;
}

.ms-option {
  height: 60rpx;
  line-height: 60rpx;
  border-top: 1px solid #e2e2e2;
  padding: 8rpx 6px;
  text-align: left;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-size: 14px;
}

.ms-item:first-child {
  border-top: none;
}

.icon-right, .icon-down, .icon-up {
  display: inline-block;
  padding-right: 13rpx;
  position: absolute;
  right: 20rpx;
  top: 16rpx;
}

.icon-right::after, .icon-down::after, .icon-up::after {
  content: "";
  display: inline-block;
  position: relative;
  bottom: 2rpx;
  margin-left: 10rpx;
  height: 10px;
  width: 10px;
  border: solid #bbb;
  border-width: 2px 2px 0 0;
}

.icon-right::after {
  -webkit-transform: rotate(45deg);
  transform: rotate(45deg);
}

.icon-down::after {
  bottom: 14rpx;
  -webkit-transform: rotate(135deg);
  transform: rotate(135deg);
}

.icon-up::after {
  bottom: 0rpx;
  -webkit-transform: rotate(-45deg);
  transform: rotate(-45deg);
}

　　select.js

Component({
  /**
   * 组件的属性列表
   */
  properties: {
    propArray: {
      type: Array,
    },
    selectText: String,
  },
  /**
   * 组件的初始数据
   */
  data: {
    selectShow: false,//初始option不显示
    // selectText: "请选择",//初始内容
  },
  /**
   * 组件的方法列表
   */
  methods: {
    //option的显示与否
    selectToggle: function () {
      var nowShow = this.data.selectShow;//获取当前option显示的状态

      this.setData({
        selectShow: !nowShow
      })
    },
    //设置内容
    setText: function (e) {
      var nowData = this.properties.propArray;//当前option的数据是引入组件的页面传过来的，所以这里获取数据只有通过this.properties
      var nowIdx = e.target.dataset.index;//当前点击的索引
      var nowText = nowData[nowIdx].name || nowData[nowIdx].value || nowData[nowIdx];//当前点击的内容
      
      this.setData({
        selectShow: false,
        selectText: nowText,
      })
      this.triggerEvent('select', nowData[nowIdx])
    }
  }
})

　　select.json

{
    "component": true,
    "usingComponents": {}
}

2、在想要引入的页面使用

　　index.jxml

<view class="select_item" >
     <select prop-array='{{selectArray1}}' selectText="{{selectText1}}"  bind:select='select1'></select>
     <select prop-array='{{selectArray2}}' selectText="{{selectText2}}"  bind:select='select2'></select>
</view>

　　index.css

.select_item{
　　display: flex;
　　justify-content: space-around;
　　margin-top: 160rpx;
}

　　index.js

Page({
     
      data:{
           selectArray1: [
              {id:1,text:'苹果'}，
               {id:2,text:'梨子'}
           ],
           selectArray2: [
               {id:1,text:'语文'}，
               {id:2,text:'数学'}
           ],
            selectText1: '品牌',
            selectText2: '类别',
      },

　　　　// 下拉框选中
    　　select1(e){
          console.log(e)
          ....
    　　},
       select2(e){
          console.log(e)
          .......
       },

}) 

　　index.json

{
    "navigationBarTitleText": "",
    "navigationBarBackgroundColor": "#fff",
    "usingComponents": {
        "select": "/component/select/select"
    }
}

总结，主要就是父子组件之间传递数据和方法的问题