微信小程序scroll-view点击项自动居中效果的实现

<scroll-view scroll-x scroll-left="{{scrollLeft}}" scroll-with-animation class="scroll-view">
 <view class="class-item" wx:for="{{classList}}" wx:key="id" bindtap="switchClass">
  <text class="name">{{item.className}}</text>
 </view>
</scroll-view>
onReady(){
 wx.createSelectorQuery().select('.scroll-view').boundingClientRect((rect)=>{
  this.data.scrollViewWidth = Math.round(rect.width)
 }).exec()
},
switchClass(){
 let offsetLeft = e.currentTarget.offsetLeft
 this.setData({
  scrollLeft: offsetLeft - this.data.scrollViewWidth/2
 })
}