1.新建自定义指令文件如下:
2.文件中插入一下代码:
import { App, Directive, DirectiveBinding, nextTick } from 'vue' import { throttle } from 'lodash-es' import ResizeObserver from 'resize-observer-polyfill' import { floor, isArray, isFunction } from 'lodash-es' interface TYPE1 extends DirectiveBinding { value: { rect: Array<Number> callback: Function } } interface TYPE2 extends DirectiveBinding { value: Array<Number> } function handler(el: HTMLElement, binding) { const { width, height, callback } = binding const { clientWidth, clientHeight } = el.parentElement const widthScale = floor(clientWidth / width, 2) const heightScale = floor(clientHeight / height, 2) const scale = widthScale < heightScale ? widthScale : heightScale el.style.setProperty('transform', 'scale(' + scale + ')') el.style.setProperty('top', (clientHeight - height) / 2 + 'px') el.style.setProperty('left', (clientWidth - width) / 2 + 'px') isFunction(callback) && callback(scale) } const containDirective: Directive = { mounted(el: HTMLElement, binding: TYPE1 | TYPE2) { const parent: HTMLElement | null = el.parentElement if (!parent) { throw new Error('v-contain指令所在的dom需要一个容器') } let width, height, callback if (isArray(binding.value)) { const [w, h] = binding.value width = w height = h } else { const [w, h] = binding.value.rect width = w height = h callback = binding.value.callback } parent.style.setProperty('position', 'relative') el.style.setProperty('position', 'absolute') el.style.setProperty('width', width + 'px') el.style.setProperty('height', height + 'px') const handleResize = throttle(() => { handler(el, { width, height, callback }) }, 200) const resizeObserver = new ResizeObserver(handleResize) resizeObserver.observe(parent) el['data-resizeObserver'] = resizeObserver nextTick(() => { handler(el, { width, height, callback }) }) }, unmounted(el) { el['data-resizeObserver']?.disconnect() el['data-resizeObserver'] = null } } export function setupContain(app: App) { app.directive('contain', containDirective) }
3.在main.js中挂在这个指令
4.在需要控制比例的div上使用该指令
标签:el,style,vue,const,callback,适配,height,width,大屏 From: https://www.cnblogs.com/cscredis/p/17141807.html