You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
70 lines
1.3 KiB
70 lines
1.3 KiB
1 year ago
|
<template>
|
||
|
|
<view>
|
||
|
|
<page-head :title="title"></page-head>
|
||
|
|
<view class="uni-padding-wrap uni-common-mt">
|
||
|
|
<view class="uni-title uni-common-mt">
|
||
|
|
{{appear ? '小球出现' : '小球消失'}}
|
||
|
|
</view>
|
||
|
|
<scroll-view class="scroll-view" scroll-y>
|
||
|
|
<view class="scroll-area">
|
||
|
|
<text class="notice">向下滚动让小球出现</text>
|
||
|
|
<view class="ball"></view>
|
||
|
|
</view>
|
||
|
|
</scroll-view>
|
||
|
|
</view>
|
||
|
|
</view>
|
||
|
|
</template>
|
||
|
|
<script>
|
||
|
|
let observer = null;
|
||
|
|
export default {
|
||
|
|
data() {
|
||
|
|
return {
|
||
|
|
appear: false,
|
||
|
|
title:'intersectionObserver'
|
||
|
|
}
|
||
|
|
},
|
||
|
|
onReady() {
|
||
|
|
observer = uni.createIntersectionObserver(this);
|
||
|
|
observer.relativeTo('.scroll-view').observe('.ball', (res) => {
|
||
|
|
if (res.intersectionRatio > 0 && !this.appear) {
|
||
|
|
this.appear = true;
|
||
|
|
} else if (!res.intersectionRatio > 0 && this.appear) {
|
||
|
|
this.appear = false;
|
||
|
|
}
|
||
|
|
})
|
||
|
|
},
|
||
|
|
onUnload() {
|
||
|
|
if (observer) {
|
||
|
|
observer.disconnect()
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
</script>
|
||
|
|
<style>
|
||
|
|
.scroll-view {
|
||
|
|
height: 400rpx;
|
||
|
|
background: #fff;
|
||
|
|
border: 1px solid #ccc;
|
||
|
|
box-sizing: border-box;
|
||
|
|
}
|
||
|
|
|
||
|
|
.scroll-area {
|
||
|
|
height: 1300rpx;
|
||
|
|
display: flex;
|
||
|
|
flex-direction: column;
|
||
|
|
align-items: center;
|
||
|
|
}
|
||
|
|
|
||
|
|
.notice {
|
||
|
|
margin-top: 150rpx;
|
||
|
|
margin: 150rpx 0 400rpx 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
.ball {
|
||
|
|
width: 200rpx;
|
||
|
|
height: 200rpx;
|
||
|
|
background: #4cd964;
|
||
|
|
border-radius: 50%;
|
||
|
|
}
|
||
|
|
</style>
|