unilateralScroll 方法是动画主事件
enterFromBelow 方法是鼠标从上向下滚动事件
enterFromAbove 方法是鼠标从下向上滚动事件
Action["事件名"] 是使用自定事件
typescript
// index.js 文件
/** 从下进入事件 -- FromLeftToRight 默认动画 */
const enterFromBelow = (el, event) => Action[event && event.length ? event[0] : 'FromLeftToRight'](el);
/** 从上进入事件 -- FromRightToLeft 默认动画 */
const enterFromAbove = (el, event) => Action[event && event.length ? event[1] : 'FromRightToLeft'](el);
/** 鼠标滚动事件 */
export const unilateralScroll = (el, event) => {
if (event.value && event.value.length != 0 && event.value.length != 2) throw new Error('Event value must be an array with two elements or without any value');
if (event.value && event.value.length == 2) {
if (Action[event.value[0]] == undefined) throw new Error(event.value[0] + ' Action must be a valid method action name');
if (Action[event.value[1]] == undefined) throw new Error(event.value[1] + ' Action must be a valid method action name');
}
/** 进入方式 0：未进入 1：进入 2：离开 */
let way = 0;
/** 定义滚动条滚动方向 */
let scrollType = true;
/** 获取初始滚动位置 */
let scrollPos = window.scrollY || document.documentElement.scrollTop;
/** 监听滚动条事件 */
window.addEventListener("scroll", function () {
/** 确定新的滚动位置 */
const newScrollPos = window.scrollY || document.documentElement.scrollTop;
newScrollPos > scrollPos ? scrollType = true : scrollType = false;
/** 更新滚动位置 */
scrollPos = newScrollPos;
/** 不同方向进入可视区域 */
if (scrollType && way != 0) way == 1 ? enterFromBelow(el, event.value) : '离开事件';
else if (!scrollType && way != 0) way == 1 ? enterFromAbove(el, event.value) : '离开事件';
});
/** 观察元素 */
const callback = (entries) => entries.forEach((entry) => entry.isIntersecting ? way = 1 : way = 2);
/** 创建一个观察者 */
new IntersectionObserver(callback, { threshold: 0 }).observe(el);
}这里是默认事件处理，可自定义内容事件
typescript
// action.js 文件
export default class Action {
/** 从下方进入可视窗口后，左边先滚动，右边固定，
* 左边滚动结束，固定左边，右边开始滚动，
* 到达盒子底边，左右固定在盒子底边
*/
static FromLeftToRight = (el) => {
if (el.children.length < 2) throw new Error('Element must have at least two children');
let dom1 = el.children[0];
let dom2 = el.children[1];
el.style.height = dom1.offsetHeight + dom2.offsetHeight - window.innerHeight + 20 + "px";
/** 判断父元素距离顶部可视窗口的距离是否小于等于0 */
if (el.getBoundingClientRect().top <= 0 && el.getBoundingClientRect().top >= -500) {
dom1.style.top = 0;
dom2.style.top = 0;
dom2.style.position = "fixed";
}
let bottom = window.innerHeight - dom1.getBoundingClientRect().bottom;
/** 判断左侧元素距离底部可视窗口的距离是否大于等于0 */
if (bottom >= 0 && bottom < 500) {
dom1.style.top = '';
dom1.style.bottom = 0;
dom1.style.position = "fixed";
dom2.style.position = "absolute";
dom2.style.top = dom1.offsetHeight - window.innerHeight + 20 + "px";
}
let pb = window.innerHeight - el.getBoundingClientRect().bottom;
/** 判断父元素距离底部可视区域的距离 */
if (pb >= 0 && pb < 500) {
dom1.style.position = "absolute";
}
};
/** 从上方进入可视窗口后，右边先滚动，左边固定，
* 右边滚动结束，固定右边，、左边开始滚动，
* 到达盒子顶边，左右固定在盒子顶边
*/
static FromRightToLeft = (el) => {
if (el.children.length < 2) throw new Error('Element must have at least two children');
let dom1 = el.children[0];
let dom2 = el.children[1];
/** 判断父元素距离顶部可视窗口的距离是否大于等于0 */
if (el.getBoundingClientRect().bottom >= 0 && el.getBoundingClientRect().bottom < 500) {
dom1.style.top = '';
dom1.style.bottom = 0;
dom1.style.position = "absolute";
dom2.style.top = '';
dom2.style.bottom = 0;
dom2.style.position = "absolute";
}
let pb = window.innerHeight - el.getBoundingClientRect().bottom;
/** 判断父元素距离底部可视区域的距离 */
if (pb <= 0 && pb > -500) {
dom1.style.top = "";
dom1.style.bottom = 0;
dom1.style.position = "fixed";
}
let top = dom2.getBoundingClientRect().top;
/** 判断右侧元素距离顶部可视窗口的距离是否大于等于0 */
if (top >= 0 && top < 500) {
dom1.style.top = 0;
dom1.style.bottom = '';
dom1.style.position = "absolute";
dom2.style.top = 0;
dom2.style.position = "fixed";
}
/** 判断父元素距离顶部可视窗口的距离是否小于等于0 */
let ct = el.getBoundingClientRect().top;
if (ct >= 0 && ct < 500) {
dom2.style.top = 0;
dom2.style.position = "absolute";
}
};
// 自定义事件
static "事件名" = () => {};
}这里通过 vue 指令，在 vue 中使用。
typescript
// main.js 文件
import Vue from 'vue'
import App from './App.vue'
import router from './router'
import { unilateralScroll } from "./utils/index";
Vue.config.productionTip = false;
// 设置指令, binding, vnode
Vue.directive('unilateralScroll', { inserted(el, binding) { unilateralScroll(el, binding) }});
new Vue({
router,
store,
render: h => h(App)
}).$mount('#app');
typescript
// app.vue 文件
<template>
<div id="app">
<div class="box"></div>
<!-- v-unilateralScroll="['从上向下滚动事件', '从下向上滚动事件']" -->
<div class="container" v-unilateralScroll>
<div class="c1">
<div>···内容1</div>
</div>
<div class="c2">
<div>···内容2</div>
</div>
</div>
<div class="flooter"></div>
</div>
</template>
<style lang="scss">
* {
margin: 0;
padding: 0;
}
html,
body {
width: 100%;
height: 100%;
box-sizing: border-box;
}
body {
overflow-y: auto;
}
.box {
width: 100%;
height: 120vh;
background-color: #b1ffb1;
}
.container {
width: 100%;
overflow: hidden;
position: relative;
background-color: #4787e7b9;
}
.c1 {
left: 0;
width: 50%;
position: absolute;
background-color: #cf7bcf;
}
.c2 {
right: 0;
width: 50%;
position: absolute;
background-color: #cfad7b;
}
.flooter {
width: 100%;
height: 130vh;
overflow: hidden;
background-color: black;
}
</style>这里展示vue实现视频
左右分屏滚动