mpvue实现左侧导航与右侧内容的联动

<scroll-view class="menu-wrapper" scroll-y>
 <ul>
 <li class="menu-item"
 v-for="(item,index) in goods"
 :class="index===currentIndex ? 'current' : ''"
 :key="index"
 @tap="selectMenu(index)">
  {{item.name}}
 </li>
 </ul>
</scroll-view>
<scroll-view scroll-y
  :scroll-into-view="contentId"
  scroll-with-animation="true"
  class="foods-wrapper">
 <ul>
 <li v-for="(item,i) in goods"
 :id="'con_'+i"
 class="food-list food-list-hook" :key="i">
 </li>
 </ul>
<scroll-view>

data() {
 return {
 goods: [],
 contentId: '', // 每个food-list的id，scroll-into-view滚动到对应的id
 currentIndex: 0
 }
},
methods: {
 selectMenu(index) {
 this.contentId = `con_${index}`
 this.currentIndex = index
 }
}

<scroll-view class="menu-wrapper"
  :scroll-into-view="navId"
  scroll-with-animation="true"
  scroll-y>
 <ul class="menu-ul">
 <li class="menu-item"
 v-for="(item,index) in goods"
 :id="'nav_'+index"
 :class="index===currentIndex ? 'current' : ''"
 :key="index"
 @tap="selectMenu(index)">
  {{item.name}}
 </li>
 </ul>
</scroll-view>
<scroll-view scroll-y
  @scroll="onScroll"
  :scroll-into-view="contentId"
  scroll-with-animation="true"
  class="foods-wrapper">
 <ul>
 <li v-for="(item,i) in goods"
 :id="'con_'+i"
 class="food-list food-list-hook" :key="i">
 </li>
 </ul>
</scroll-view>

export default{
 data() {
 return {
 goods: [],
 contentId: '', // 每个food-list的id，scroll-into-view滚动到对应的id
 navId: '', // 导航模块对应的id，用来联动内容区域
 currentIndex: 0,
 navulHeight: 0, // 导航里ul高度
 navItemHeight: 0, // 每个导航高度
 listHeight: [], // foods内部块的高度
 contentHeight: [], // 内容区域scroll-view高度
 }
 },
 watch: {
 currentIndex() {
 console.log(this.currentIndex)
 if (this.contentHeight < this.navulHeight) {
 let h = this.currentIndex  this.navItemHeight
 if (h > this.contentHeight) {
  // 导航滑动
  this.navId = `nav_${this.currentIndex}`
 } else {
  this.navId = 'nav_0'
 }
 }
 }
 },
 methods: {
 selectMenu(index) {
 this.contentId = `con_${index}`
 this.navId = `nav_${index}`
 this.currentIndex = index
 },
 onScroll(e) {
 this.contentId = ''
 let scrollTop = e.target.scrollTop
 // console.log(scrollTop)
 let length = this.listHeight.length
 if (scrollTop >= this.listHeight[length - 1] - this.contentHeight) {
 return
 } else if (scrollTop > 0 && scrollTop < this.listHeight[0]) {
 this.currentIndex = 0
 }
 for (let i = 0; i < length; i++) {
 if (scrollTop >= this.listHeight[i - 1] && scrollTop < this.listHeight[i]) {
  this.currentIndex = i
 }
 }
 // console.log(this.currentIndex)
 },
 getFoodHeight() {
 var query = wx.createSelectorQuery()
 let h = 0
 query.selectAll('.food-list-hook').boundingClientRect((rects) => {
 // console.log(rects)
 rects.forEach((rect) => {
  h += rect.height
  this.listHeight.push(h)
 })
 // console.log(this.listHeight)
 })
 query.select('.foods-wrapper').boundingClientRect((rect) => {
 this.contentHeight = rect.height
 })
 query.select('.menu-ul').boundingClientRect((rect) => {
 this.navulHeight = rect.height
 })
 query.select('.menu-item').boundingClientRect((rect) => {
 this.navItemHeight = rect.height
 }).exec()
 }
 }，
 watch: {
 goods() {
 // 获取模块高度，即food-list
 setTimeout(() => {
 this.getFoodHeight()
 }, 60)
 }
 }
}