微信小程序scroll-view组件实现滚动动画

<view class="right-nav">  <view bindtap="getCurrentCode" class="{{chooseIndex == index ? '.city-list-active' : ''}}" wx:for="{{cityList}}" style="height:{{codeHeight}}px" data-code="{{item.code}}" data-index="{{index}}">  {{item.code}}  </view></view><view class="city-layer {{isShowLayer ? '' : 'layer-hide'}}"> {{codeY}}</view><view class="current-choose-city">当前选择机场：{{chooseCity}}</view><scroll-view class="city-scroll" scroll-y="true" scroll-into-view="{{codeY}}" scroll-with-animation="true" style="height:{{cityHeight}}px" bindscroll="scroll">  <view class="city-box" wx:for="{{cityList}}" wx:key="{{item.code}}">    <view class="city-code" id="{{item.code}}">{{item.code}}</view>    <view class="city-list" wx:for="{{item.cityList}}" wx:for-item="city" bindtap="getChooseCity" data-city="{{city}}">        {{city}}     </view>   </view></scroll-view>

.current-choose-city{ position: fixed; width: 100%; height: 50px; line-height: 50px; padding: 0 10px; top: 0; left: 0; background-color: #fff; z-index: 10;}.right-nav{ width: 30px; color: #888; text-align: center; position: fixed; bottom: 0; right: 0; background-color: rgb(200, 200, 200); z-index: 9;}.city-scroll{padding-top: 50px;}.city-code{ background-color: #f7f7f7;}.city-list,.city-code{ height: 39px; line-height: 40px; padding: 0 30px 0 10px; overflow: hidden; border-bottom: 1px solid #c8c7cc;}.city-list-active{color:#007aff;}/*提示点击的字母 */.city-layer{ width: 70px; height: 70px; line-height: 70px; text-align: center; border-radius: 50%; color: #fff; background-color: rgba(0, 0, 0, .7); position: fixed; top: calc(50% - 35px); left:calc(50% - 35px); z-index: 11;}.layer-hide{display: none;}

var city_list = require('./city.js');Page({ data: {  cityList: city_list.city,  chooseCity: '您还未选择机场！',  isShowLayer: false,  chooseIndex: 0,  codeY: 'A',  codeHeight: null,  cityHeight:null }, onLoad (options) {  var windowHeight = wx.getSystemInfoSync().windowHeight;  this.setData({    codeHeight: (windowHeight - 50) / this.data.cityList.length,   cityHeight: windowHeight - 50,  }); }, getCurrentCode(e){  var self = this;  this.setData({    codeY: e.target.dataset.code,   chooseIndex: e.target.dataset.index,   isShowLayer: true   })  setTimeout(() => {   self.setData({ isShowLayer: false })  },500); }, getChooseCity(e){  this.setData({ chooseCity: e.target.dataset.city }); }})