Element UI Dialog 可拖拽移动

发布于 2021-10-11  249 次阅读


步骤

1. 新建文件 directives.js

import Vue from 'vue';
   
// v-dialogDrag: 弹窗拖拽属性
Vue.directive('dialogDrag', {
    bind(el, binding, vnode, oldVnode) {
        const dialogHeaderEl = el.querySelector('.el-dialog__header');
        const dragDom = el.querySelector('.el-dialog');
        //dialogHeaderEl.style.cursor = 'move';
        dialogHeaderEl.style.cssText += ';cursor:move;'
        dragDom.style.cssText += ';top:0px;'
     
        // 获取原有属性 ie dom元素.currentStyle 火狐谷歌 window.getComputedStyle(dom元素, null);
        const sty = (function() {
            if (window.document.currentStyle) {
                return (dom, attr) => dom.currentStyle[attr];
            } else{
                return (dom, attr) => getComputedStyle(dom, false)[attr];
            }
        })()   
         
        dialogHeaderEl.onmousedown = (e) => {
            // 鼠标按下,计算当前元素距离可视区的距离
            const disX = e.clientX - dialogHeaderEl.offsetLeft;
            const disY = e.clientY - dialogHeaderEl.offsetTop;
             
            const screenWidth = document.body.clientWidth; // body当前宽度
            const screenHeight = document.documentElement.clientHeight; // 可见区域高度(应为body高度,可某些环境下无法获取)
             
            const dragDomWidth = dragDom.offsetWidth; // 对话框宽度
            const dragDomheight = dragDom.offsetHeight; // 对话框高度
             
            const minDragDomLeft = dragDom.offsetLeft;
            const maxDragDomLeft = screenWidth - dragDom.offsetLeft - dragDomWidth;
             
            const minDragDomTop = dragDom.offsetTop;
            const maxDragDomTop = screenHeight - dragDom.offsetTop - dragDomheight;
         
             
            // 获取到的值带px 正则匹配替换
            let styL = sty(dragDom, 'left');
            let styT = sty(dragDom, 'top');
         
            // 注意在ie中 第一次获取到的值为组件自带50% 移动之后赋值为px
            if(styL.includes('%')) {
                styL = +document.body.clientWidth * (+styL.replace(/\%/g, '') / 100);
                styT = +document.body.clientHeight * (+styT.replace(/\%/g, '') / 100);
            }else {
                styL = +styL.replace(/\px/g, '');
                styT = +styT.replace(/\px/g, '');
            };
             
            document.onmousemove = function (e) {
                // 通过事件委托,计算移动的距离
                let left = e.clientX - disX;
                let top = e.clientY - disY;
                 
                // 边界处理
                if (-(left) > minDragDomLeft) {
                    left = -(minDragDomLeft);
                } else if (left > maxDragDomLeft) {
                    left = maxDragDomLeft;
                }
                 
                if (-(top) > minDragDomTop) {
                    top = -(minDragDomTop);
                } else if (top > maxDragDomTop) {
                    top = maxDragDomTop;
                }
         
                // 移动当前元素
                dragDom.style.cssText += `;left:${left + styL}px;top:${top + styT}px;`;
            };
         
            document.onmouseup = function (e) {
                document.onmousemove = null;
                document.onmouseup = null;
            };
        }
    }
})

2.在main.js中引入

import './utils/directives'

3. 在el-dialog标签中加入v-dialogDrag属性

属性 close-on-click-modal 取消自动关闭
属性 modal:关闭遮罩
属性 class:注意class添加,overflow hidden否则有溢出