uniapp滑动到一定的高度后固定某个元素到顶部效果demo（整理）

<template>
  <view>
    <view>测试</view>
    <view>测试</view>
    <view>测试</view>
    <view>测试</view>
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    <view class="topBox" :class="temp==1?'boxStyle':''">测试固定顶部测试固定顶部</view>
    <view>测试</view>
    <view>测试</view>
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  </view>
</template>
<script>
  export default {
    data() {
      return {
        temp: 0,
        myScroll: 0,
      }
    },
    onLoad(e) {
      //获取目标板块到顶部的距离
      uni.createSelectorQuery().select('.topBox').boundingClientRect(res => {
        this.myScroll = res.top;
        console.log(this.myScroll, 'this.myScroll-------')
      }).exec();
    },
    methods: {
      onPageScroll(e) {
        // console.log(e,'eeeee')
        if (e.scrollTop > this.myScroll) {
          this.temp = 1
        } else {
          this.temp = 0
        }
      },
    }
  }
</script>
<style>
  .boxStyle {
    width: 100%;
    height: 80rpx;
    position: fixed;
    top: 0;
    left: 0;
    background: #fff;
  }
</style>