Perbincangan ringkas tentang cara melaksanakan fungsi 'penilaian lima bintang' dalam program mini (menyokong klik dan gelongsor)

/*wxss 一行内展示五颗星并设置其间距为30rpx*/
.scoreContent {display: inline-block;}
.starLen {margin-right: 30rpx;display: inline-block;}
.scoreContent .starLen:last-child {margin-right: 0;}
.star {width: 80rpx;height: 80rpx;vertical-align: text-bottom;display: inline-block;}

/*wxml 每个starLen元素上绑定 touchMove touchEnd tap事件*/
<view class="scoreContent" id="scoreContent">
  <block wx:for=&#39;{{5}}&#39; wx:key=&#39;item&#39;>
    <!-- 遍历评分列表 -->
    <view class=&#39;starLen&#39; catchtouchmove=&#39;changeScore&#39; catchtouchend="changeScoreEnd" catchtap=&#39;setScore&#39; data-index="{{index}}">
      <!-- 使用三目运算符来动态变化显示的是哪张图片,score是js中的分数,index是scoreArray的下标 -->
      <image class=&#39;star&#39; src="{{score>index?(score>index+0.5?fullStarUrl:halfStarUrl):nullStarUrl}}" />
    </view>
  </block>
</view>

//取 score与index下标做比较,默认score为0
score<index    展示nullStar.png

score>index+0.5  展示fullStar.png

index<score<=index+0.5 展示halfStar.png

  /**
   * 组件的初始数据
   */
  data: {
    fullStarUrl: '/images/full.png', //满星图片
    halfStarUrl: '/images/half.png', //半星图片
    nullStarUrl: '/images/null.png', //空星图片
    score: 0, //评价分数
    rate: 2,  //设计稿宽度÷屏幕实际宽度
    startX: 0, //第一颗星screenX的距离
  },

//设定比率rate与第一颗星screenX    组件初始化attached  或者 页面初始化onShow
attached: function () { // 在组件实例进入页面节点树时执行
  let { screenWidth } = wx.getSystemInfoSync();
  let rate = screenWidth / 750;
  this.setData({
    rate: rate
  })
  
  const query = this.createSelectorQuery();
  query.select('#scoreContent').boundingClientRect((res)=> {
    this.setData({
      startX: res.left
    })
  }).exec()
},