JavaScript拖拽，点击上传文件组件封装
遇到一个拖拽上传图片的需求，研究了一下功能，以共后续学习使用，用原生写了一个小组件！
index.html
DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>File Upload with Progress Bar | CodingNepaltitle>
<link rel="stylesheet" href="style.css">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/5.15.3/css/all.min.css"/>
head>
<body>
<div class="wrapper" id="draged">
<header>File Uploader JavaScriptheader>
<form action="#">
<input class="file-input" type="file" name="file" hidden multiple>
<i class="fas fa-cloud-upload-alt">i>
<p class="hint">
Browse File to Upload<br>
Or drag it here
p>
form>
<section class="progress-area">section>
<section class="uploaded-area">section>
<div class="textPreread" onclick="closeText()">
<div id="content">div>
div>
div>
<script>
const form = document.querySelector("form"),
draged = document.getElementById('draged')
fileInput = document.querySelector(".file-input"),
progressArea = document.querySelector(".progress-area"),
uploadedArea = document.querySelector(".uploaded-area");
// form click event
form.addEventListener("click", () =>{
fileInput.click();
});
fileInput.onchange = ({target})=>{
let file = target.files
console.log(file);
[...file].forEach(item=>{
Preview(item)
})
}
//拖拽结束事件
draged.addEventListener('dragover',handleDrageover)
function handleDrageover(e){
// 阻止默认事件。不要让浏览器默认事件来干扰。拖拽操作
e.preventDefault()
draged.classList.add('dragover')
}
// 拖拽离开事件
draged.addEventListener('dragleave',handleDragLeave)
function handleDragLeave(e){
e.preventDefault()
draged.classList.remove('dragover')
}
// 拖拽释放
draged.addEventListener('drop',handleDrop)
function handleDrop(e){
e.preventDefault()
// 将dom元素拖拽进可放置区域
// const draggedId = e.dataTransfer.getData('text/plain') //标注： 拖拽dom元素
// draged.appendChild(document.getElementById('drag')) //标注： 拖拽dom元素
// draged.classList.add('dropSucess')
// console.log(...e.dataTransfer.items)
// 拖拽也支持外部拖拽文件，图片进来，可以在该事件中监听，
// 如果是拖拽文件需要注释上面 “标注：拖拽dom元素” 两行代码
// 遍历e.dataTransfer.items 属性去做操作
// ...e.dataTransfer.items 可能为空，做一个判空处理
if([...e.dataTransfer.items]){
// 拖拽文件，解构成数组，如果是多个需要遍历，所以调用forEach
[...e.dataTransfer.items].forEach(item=>{
console.log(item,'000');
// 如果拖拽进来的是文件夹
let Directory = item.webkitGetAsEntry()
if(Directory.isDirectory) {
alert('请尝试压缩后上传')
}
// console.log(Directory);
// 通过kind属性判断拖拽进来的是不是文件
if(item.kind === 'file') {
const file = item.getAsFile()
//createPreview 生成预览,比如判断图片
Preview(file)
}
})
}
}
// 图片处理
function Preview(file){
// 如果是图片类型的文件
if(file.type.startsWith('image')){
// 创建一个图片元素
const image = document.createElement('img')
// 根据文件对象创建一个ObjectURL，用作src属性
image.src = URL.createObjectURL(file)
// 图片加载成功过后，ObjectURL就没有用了，就回收这个ObjectURL
file.onload = function(){
URL.revokeObjectURL(this.src)
}
// 把图片追加到可放置区域，及直接将图片显示到浏览器。
// draged.appendChild(image)
// 如果只显示名字和图片大小
console.log(file);
console.log(file.name,Math.ceil(file.size/1024)+'kb');
const fileName = document.createElement('div')
// 注意：模板字符串中添加点击事件要带引号
fileName.innerHTML = `
${image.src}
')" class='name' >${file.name}
体积:${Math.ceil(file.size/1024)}kb
`
fileName.classList.add('fileName')
uploadedArea.appendChild(fileName)
} else if(file.type.startsWith('application') || file.type.startsWith('audio')|| file.type.startsWith('video')){
const fileName = document.createElement('div')
fileName.innerHTML = `
${file.name}
体积:${Math.ceil(file.size/1024)}kb
`
fileName.classList.add('fileName')
uploadedArea.appendChild(fileName)
} else if(file.type.startsWith('text')){
new Promise(resolve=>{
let co = ''
let reader = new FileReader
reader.readAsText(file,'utf-8')
reader.onload = (evt)=>{
// 读取txt文件
let data = evt.target.result
resolve(data)
}
}).then( res=>{
const fileName = document.createElement('div')
// 如果使用模板字符串传参，会因为特殊字符，导致传参发生位置错误
let on = {}
on.text = res
fileName.innerHTML = `
${file.name}
体积:${Math.ceil(file.size/1024)}kb
`
fileName.classList.add('fileName')
fileName.onclick = function(){
showText.call(this,on)
}
uploadedArea.appendChild(fileName)
// 这两种写法都会立即执行预览事件，并且只执行一次
// fileName.setAttribute('onclick',showText(on))
// fileName.addEventListener('onclick',showText(on))
})
} else {
alert('未知文件格式')
}
}
function showText(data){
// console.log(data,'data');
let text = document.getElementById('content')
text.innerText = data.text
let textFater = document.getElementsByClassName('textPreread')[0]
textFater.classList.add('textPrereadShow')
}
function closeText(){
// 点击任意位置关闭预览txt
let textFater = document.getElementsByClassName('textPreread')[0]
textFater.classList.remove('textPrereadShow')
}
// 图片预览
function showImg(img){
let obj = {
urls: [img],
current: img
}
previewImage.start(obj)
}
script>
<script src="previewImage.js">script>
body>
html>
style.css
/* Import Google font - Poppins */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600&display=swap');
*{
margin: 0;
padding: 0;
box-sizing: border-box;
font-family: "Poppins", sans-serif;
}
body{
display: flex;
align-items: center;
justify-content: center;
min-height: 100vh;
background: #6990F2;
}
#draged img {
width: 50%;
height: 50%;
object-fit: contain;
margin-top: 20px;
}
.dragover{
border: 4px orangered;
}
.dropSucess{
border: 4px green;
}
::selection{
color: #fff;
background: #6990F2;
}
.wrapper{
width: 430px;
background: #fff;
border-radius: 5px;
padding: 30px;
box-shadow: 7px 7px 12px rgba(0,0,0,0.05);
}
.wrapper header{
color: #6990F2;
font-size: 27px;
font-weight: 600;
text-align: center;
}
.wrapper form{
height: 167px;
display: flex;
cursor: pointer;
margin: 30px 0;
align-items: center;
justify-content: center;
flex-direction: column;
border-radius: 5px;
border: 2px dashed #6990F2;
}
form :where(i, p){
color: #6990F2;
}
form i{
font-size: 50px;
}
form p{
margin-top: 15px;
font-size: 16px;
}
section .row{
margin-bottom: 10px;
background: #E9F0FF;
list-style: none;
padding: 15px 20px;
border-radius: 5px;
display: flex;
align-items: center;
justify-content: space-between;
}
section .row i{
color: #6990F2;
font-size: 30px;
}
section .details span{
font-size: 14px;
}
.progress-area .row .content{
width: 100%;
margin-left: 15px;
}
.progress-area .details{
display: flex;
align-items: center;
margin-bottom: 7px;
justify-content: space-between;
}
.progress-area .content .progress-bar{
height: 6px;
width: 100%;
margin-bottom: 4px;
background: #fff;
border-radius: 30px;
}
.content .progress-bar .progress{
height: 100%;
width: 0%;
background: #6990F2;
border-radius: inherit;
}
.uploaded-area{
display: flex;
flex-direction: column;
max-height: 232px;
overflow-y: scroll;
}
.uploaded-area.onprogress{
max-height: 150px;
}
.uploaded-area::-webkit-scrollbar{
width: 0px;
}
.uploaded-area .row .content{
display: flex;
align-items: center;
}
.uploaded-area .row .details{
display: flex;
margin-left: 15px;
flex-direction: column;
}
.uploaded-area .row .details .size{
color: #404040;
font-size: 11px;
}
.uploaded-area i.fa-check{
font-size: 16px;
}
.fileName{
color: #6990F2;
cursor: pointer;
position: relative;
display: flex;
font-size: 14px;
}
.name {
max-width: 240px;
height: 20px;
overflow: hidden;
text-overflow: ellipsis;
display: -webkit-box;
-webkit-line-clamp: 1;
text-align: justify;
-webkit-box-orient: vertical;
}
.fileName span{
margin-left: 30px;
white-space: nowrap;
text-overflow:ellipsis;
overflow:hidden;
}
.hint{
text-align: center;
}
.textPreread{
position: fixed;
display: flex;
visibility: hidden;
justify-content: center;
align-items: center;
top: 0;
left: 0;
right: 0;
bottom: 0;
background-color: rgba(0, 0, 0, 0.5);
}
.textPrereadShow {
visibility: visible;
}
.textPreread #content{
overflow: auto;
height: 500px;
font-size: 12px;
width: 480px;
background-color: #fff;
}
#content::-webkit-scrollbar {
display: none; /* Chrome Safari */
}
标题 网上的一个图片预功能，bug未知，不需要预览功能，可忽略
previewImage.js
(function( global, factory ) {
//For CommonJS and CommonJS-like
if ( typeof module === "object" && typeof module.exports === "object" ) {
module.exports = global.document ?
factory( global, true ) :
function( w ) {
if ( !w.document ) {
throw new Error( "previewImage requires a window with a document" );
}
return factory( w );
};
} else {
factory( global );
}
// Pass this if window is not defined yet
}(typeof window !== "undefined" ? window : this, function(window){
var $ = {};
var style = "#__previewImage-container{padding-bottom: constant(safe-area-inset-bottom);padding-bottom: env(safe-area-inset-bottom);-ms-touch-action:none;touch-action:none;-webkit-touch-action:none;line-height:100vh;background: rgba(0,0,0,0.5);min-width:100vw;min-height:100vh;position:fixed;overflow:hidden;top:0;left:0;bottom:0;right:0;z-index: 2147483647;transition:transform .3s;-ms-transition:transform .3s;-moz-transition:transform .3s;-webkit-transition:transform .3s;-o-transition:transform .3s;transform:translate3d(100%,0,0);-webkit-transform:translate3d(100%,0,0);-ms-transform:translate3d(100%,0,0);-o-transform:translate3d(100%,0,0);-moz-transform:translate3d(100%,0,0)}#__previewImage-container .previewImage-text{position:absolute;width: 50px;height: 30px;top:.6em;text-align:center;font-size:15px;line-height:30px;color:#fff;z-index:10;padding: 0.2em 0.4em;background-color: rgba(0,0,0,0.5);border-radius: 12px;letter-spacing: 0;right:.8em}#__previewImage-container .previewImage-text .previewImage-text-index{font-size: 18px;}#__previewImage-container .previewImage-box{height:100vh;display:flex;justify-content: center;}#__previewImage-container .previewImage-box .previewImage-item{width:50vw;height:100vh;transform: scale(0.9);text-align:center;background:url() no-repeat center/auto}#__previewImage-container .previewImage-box .previewImage-item.previewImage-nobackground{background:none;}#__previewImage-container .previewImage-box .previewImage-item .previewImage-image{vertical-align:middle;width:100%}";
$.isArray = function(value) {
return Object.prototype.toString.call(value) == '[object Array]';
}
/**
* get multiple elements
* @public
*/
$.all = function(selector, contextElement) {
var nodeList,
list = [];
if (contextElement) {
nodeList = contextElement.querySelectorAll(selector);
} else {
nodeList = document.querySelectorAll(selector);
}
if (nodeList && nodeList.length > 0) {
list = Array.prototype.slice.call(nodeList);
}
return list;
}
/**
* delegate an event to a parent element
* @public
* @param array $el parent element
* @param string eventType name of the event
* @param string selector target's selector
* @param function fn
*/
$.delegate = function($el, eventType, selector, fn) {
if (!$el) { return; }
$el.addEventListener(eventType, function(e) {
var targets = $.all(selector, $el);
if (!targets) {
return;
}
for (var i=0; i<targets.length; i++) {
var $node = e.target;
while ($node) {
if ($node == targets[i]) {
fn.call($node, e);
break;
}
$node = $node.parentNode;
if ($node == $el) {
break;
}
}
}
}, false);
};
var _previewImage = function(){
this.winw = window.innerWidth||document.body.clientWidth; //窗口的宽度
this.winh = window.innerHeight||document.body.clientHeight; //窗口的高度
this.originWinw = this.winw; //存储源窗口的宽度
this.originWinh = this.winh; //存储源窗口的高度
this.marginRight = 15; //图片之间的间隔->previewImage-item的margin-right
this.imageChageMoveX = this.marginRight+this.winw; //图片切换容器的x位移量
this.imageChageNeedX = Math.floor(this.winw*(0.5)); //图片切换所需x位移量
this.cssprefix = ["","webkit","Moz","ms","o"]; //css前缀
this.version = '1.0.3'; //版本号
this.imgLoadCache = new Object(); //图片加载状态储存 key=md5(img.src),value={isload:true,elem:img};
this.scale = 1; //默认图片放大倍数
this.maxScale = 4; //图片默认最大放大倍数
this.maxOverScale = 6; //图片放大倍数最大可达到
// this.minScale = 0.5; //图片最小可放大倍数
this.openTime = 0.3; //打开图片浏览动画时间
this.slipTime = 0.6; //图片切换时间
this.maxOverWidthPercent = 0.5; //边界图片最大可拉取宽度，屏幕宽度的百分比
this.$box = false; //图片容器加载状态
this.isPreview = false; //是否正在预览图片
var $style = document.createElement('style'); //样式标签
$style.innerText = style; //加载样式
$style.type = 'text/css';
this.$container = document.createElement('div'); //加载容器
this.$container.id = '__previewImage-container'; //容器加上id
this.$container.style.width = this.winw+'px'; //加上宽度
this.$container.style.height = this.winh+'px'; //加上高度
document.body.appendChild(this.$container); //插入容器到body
document.head.appendChild($style); //插入样式到head
this.bind(); //绑定事件
}
_previewImage.prototype.start = function(obj){ //可优化 todo
var urls = obj.urls; //待预览的图片列表
var current = obj.current; //当前预览的图片地址
this.$container.innerHTML = ''; //清空容器
if(!urls||!$.isArray(urls)||urls.length==0){ //参数检测
throw new Error("urls must be a Array and the minimum length more than zero");
return
}
if(!current){ //参数检测
this.index = 0;
console.warn("current is empty,it will be the first value of urls!");
}else{
var index = urls.indexOf(current);
if(index<0){
index = 0;
console.warn("current isnot on urls,it will be the first value of urls!");
}
this.index = index; //当前图片序号
}
this.urls = urls; //所有图片url列表
this.maxLen = urls.length-1; //最大图片数 0<=index<=maxLen
this.cIndex = this.maxLen+1; //containerIndex
this.bIndex = this.maxLen+2; //boxIndex
this.imgStatusCache = new Object(); //图片信息储存
this.render(); //渲染预览模块
}
_previewImage.prototype.render = function(){
var _this = this;
if(this.$box===false){ //加载图片容器
var box = document.createElement('div');
box.className += 'previewImage-box';
this.$box = box; //更新图片容器
}else{
this.$box.innerHTML = ''; //已有图片容器-清空容器
}
var text = document.createElement('div'); //当前张数/总张数--文本标签
this.$text = text;
this.$text.className += 'previewImage-text';
this.$text.innerHTML = ""+(this.index+1)+"/"+(this.maxLen+1); //当前第几张/图片总数
this.container = this.imgStatusCache[this.cIndex] = {elem:this.$container,x:this.winw,y:0,m:0,my:0,scale:1,scalem:1}; //存储容器状态
this.box = this.imgStatusCache[this.bIndex] = {elem:this.$box,x:0,y:0,m:0,my:0,scale:1,scalem:1}; //存储图片容器状态
this.urls.forEach(function(v,i){ //图片
var div = document.createElement('div');
var hash = window.md5?md5(v+i):v+i;
var img;
var imgCache = _this.imgLoadCache[hash];
//缓存图片&&读取缓存图片
if(imgCache&&imgCache.isload){ //图片已加载--使用缓存
img = imgCache.elem;
div.className+=" previewImage-nobackground";
}else{ //图片未加载--加载图片，加入缓存
img = new Image();
img.className += 'previewImage-image';
_this.imgLoadCache[hash] = {isload:false,elem:img};
if(i == _this.index){ //将当前需要预览的图片加载
img.src = v;
img.onload = function(){
div.className+=" previewImage-nobackground";
_this.imgLoadCache[hash].isload = true;
}
}
}
_this.imgStatusCache[i] = {hash:hash,x:0,m:0,y:0,my:0,scale:_this.scale,scalem:1}; //修改缓存状态
// img.setAttribute("data-index",i); //未使用
div.className+=' previewImage-item';
div.appendChild(img);
_this.$box.appendChild(div); //将图片div加入 图片容器
})
this.$container.appendChild(this.$box); //加载图片容器
this.$container.appendChild(this.$text); //加载图片张数提示
var offsetX = -this.imageChageMoveX*this.index; //计算显示当前图片，容器所需偏移量
this.box.x = offsetX; //将图片容器所需偏移量，存入状态缓存器
this.container.x = 0; //显示预览模块
this.$container.style.display = "block";
setTimeout(function(){
_this.translateScale(_this.bIndex,0);
_this.translateScale(_this.cIndex,_this.openTime);
_this.isPreview = true;
},50);
}
_previewImage.prototype.bind = function(){
var $container = this.$container;
var _this = this;
var closePreview = function(){
_this.closePreview.call(_this);
}
var touchStartFun = function(){
_this.touchStartFun.call(_this);
}
var touchMoveFun = function(){
_this.touchMoveFun.call(_this);
}
var touchEndFun = function(){
_this.touchEndFun.call(_this);
}
// var orientationChangeFun = function(){
// var angle = screen.orientation.angle;
// var _this = this;
// if(angle==90||angle==180){
// _this.winw = _this.originWinh;
// _this.winh = _this.originWinw;
// }else{
// _this.winw = _this.originWinw;
// _this.winh = _this.originWinh;
// }
// _this.$container.style.width = _this.winw+'px'; //改变宽度
// _this.$container.style.height = _this.winh+'px'; //改变高度
// _this.imageChageMoveX = _this.marginRight+_this.winw;
// var offsetX = -_this.imageChageMoveX*_this.index; //计算显示当前图片，容器所需偏移量
// try{
// _this.box.x = offsetX; //将图片容器所需偏移量，存入状态缓存器
// _this.translateScale(_this.bIndex,0);
// }catch(e){}
// }.bind(this);
var reSizeFun = function(){
var _this = this;
_this.winw = window.innerWidth||document.body.clientWidth; //窗口的宽度
_this.winh = window.innerHeight||document.body.clientHeight; //窗口的高度
_this.originWinw = _this.winw; //存储源窗口的宽度
_this.originWinh = _this.winh; //存储源窗口的高度
_this.$container.style.width = _this.winw+'px'; //改变宽度
_this.$container.style.height = _this.winh+'px'; //改变高度
_this.imageChageMoveX = _this.marginRight+_this.winw;
var offsetX = -_this.imageChageMoveX*_this.index; //计算显示当前图片，容器所需偏移量
try{
_this.box.x = offsetX; //将图片容器所需偏移量，存入状态缓存器
_this.translateScale(_this.bIndex,0);
}catch(e){}
}.bind(this);
// window.addEventListener("orientationchange",orientationChangeFun,false);
window.addEventListener("resize",reSizeFun,false);
$.delegate($container,'click','.previewImage-item',closePreview);
$.delegate($container,'touchstart','.previewImage-item',touchStartFun);
$.delegate($container,'touchmove','.previewImage-item',touchMoveFun);
$.delegate($container,'touchend','.previewImage-item',touchEndFun);
$.delegate($container,'touchcancel','.previewImage-item',touchEndFun);
}
_previewImage.prototype.closePreview = function(){
var _this = this;
this.imgStatusCache[this.cIndex].x = this.winw;
this.translateScale(this.cIndex,this.openTime);
this.imgStatusRewrite();
this.translateScale(this.index,this.slipTime);
setTimeout(function(){
_this.$container.style.display = "none";
},this.slipTime*1000);
_this.isPreview = false;
}
_previewImage.prototype.touchStartFun = function(imgitem){
this.ts = this.getTouches();
this.allowMove = true; //行为标记
this.statusX = 0; //标记X轴位移状态
this.statusY = 0; //标记Y轴位移状态
}
_previewImage.prototype.touchMoveFun = function(imgitem){
this.tm = this.getTouches();
var tm = this.tm;
var ts = this.ts;
this.moveAction(ts,tm);
}
_previewImage.prototype.touchEndFun = function(imgitem){
var $container = this.$container;
this.te = this.getTouches();
this.endAction(this.ts,this.te);
}
_previewImage.prototype.moveAction = function(ts,tm){
if(!this.allowMove){
return
}
var imgStatus = this.getIndexImage();
var maxWidth = this.winw*0.3/imgStatus.scale;
var x0_offset = tm.x0 - ts.x0;
var y0_offset = tm.y0 - ts.y0;
if(Math.abs(y0_offset)>0){ //阻止Ios系统的浏览器环境上下滑动
event.preventDefault();
}
var imgPositionX = imgStatus.x+x0_offset;
var imgPositionY = imgStatus.y+y0_offset;
var allow = this.getAllow(this.index);
var allowX = this.allowX = allow.x;
var allowY = this.allowY = allow.y0;
if(x0_offset<=0){ //边界
this.allowX = -allowX;
}
// if(y0_offset<=0){ //边界
// allowY = this.allowY = allow.y1;
// }
// 是否允许在y轴方向滑动 imgPositionY 将有关imgPositionY 已注释，禁止y轴方向滑动
if(tm.length==1){ //单手指(图片位移)
if(imgStatus.scale>1){
// Y方向位移
if(imgPositionY>=allow.y0 && imgPositionY){ //超过窗口上边界
this.statusY = 1;
var overY = imgPositionY - allow.y0;
imgStatus.my = allow.y0-imgStatus.y+this.getSlowlyNum(overY,maxWidth);
}else if(imgPositionY<=allow.y1){ //超过窗口下边界
this.statusY = 1;
var overY = imgPositionY - allow.y1;
imgStatus.my = allow.y1-imgStatus.y+this.getSlowlyNum(overY,maxWidth);
}else{
this.statusY = 2;
imgStatus.my = y0_offset;
}
//X方向位移
if(x0_offset<0&&imgStatus.x<=-allowX){ //左滑->初始状态到达或超过右边界->图片平滑移动到达条件-切换下一张
this.statusX = 1;
this.box.m = x0_offset; //更新位移信息
if(this.index==this.maxLen){ //box到达右边界
this.box.m = this.getSlowlyNum(x0_offset); //阻尼效果
}
this.translateScale(this.bIndex,0);
this.translateScale(this.index,0);
}else if(x0_offset>0&&imgStatus.x>=allowX){ //右滑->初始状态到达或超过左边界->图片平滑移动到达条件-切换上一张
this.statusX = 2;
this.box.m = x0_offset;
if(this.index==0){ //box到达左边界
this.box.m = this.getSlowlyNum(x0_offset); //阻尼效果
}
this.translateScale(this.bIndex,0);
this.translateScale(this.index,0);
}else{ //初始状态未到边界->图片平滑移动到边界->阻尼移动
if(x0_offset==0){
return
}
this.statusX = 3;
imgStatus.m = x0_offset;
if(imgPositionX>=allowX){ //右滑到达左边界
this.statusX = 4;
var overX = imgPositionX - allowX;
imgStatus.m = allowX-imgStatus.x+this.getSlowlyNum(overX,maxWidth);
}
if(imgPositionX<=-allowX){ //左滑到达右边界
this.statusX = 4;
var overX = imgPositionX + allowX;
imgStatus.m = -allowX-imgStatus.x+this.getSlowlyNum(overX,maxWidth);
}
this.translateScale(this.index,0);
}
}else{ //scale == 1;
if(Math.abs(y0_offset)>5&&this.statusX != 5){ //长图片处理
var $img = this.getJqElem(this.index);
var imgBottom = $img.height-this.winh;
// if(1){
if(y0_offset>0&&imgPositionY>0){
// 是否允许y轴方向移动
// this.statusX = 7;
// this.allowY = 0;
// imgStatus.my = - imgStatus.y + this.getSlowlyNum(imgPositionY,maxWidth);
}else if(y0_offset<0&&imgPositionY<-imgBottom){
// this.statusX = 7;
// if($img.height>this.winh){
// var overY = imgPositionY + imgBottom;
// this.allowY = -imgBottom;
// imgStatus.my = -imgBottom - imgStatus.y + this.getSlowlyNum(overY,maxWidth);
// }else{
// this.allowY = 0;
// imgStatus.my = - imgStatus.y + this.getSlowlyNum(imgPositionY,maxWidth);
// }
}else{
this.statusX = 6;
imgStatus.my = y0_offset;
}
this.translateScale(this.index,0);
}else{
if(this.statusX == 6){
return
}
this.statusX = 5;
if((this.index==0&&x0_offset>0)||(this.index==this.maxLen&&x0_offset<0)){ //box到达左右边界
this.box.m = this.getSlowlyNum(x0_offset);
}else{
this.box.m = x0_offset;
}
this.translateScale(this.bIndex,0);
}
}
}else{ //多手指(图片放大缩小)
var scalem = this.getScale(ts,tm)
var scale = scalem*imgStatus.scale;
if(scale>=this.maxScale){ //达到最大放大倍数
var over = scale - this.maxScale;
scale = this.maxScale+this.getSlowlyNum(over,this.maxOverScale);
scalem = scale/imgStatus.scale;
}
imgStatus.scalem = scalem;
this.translateScale(this.index,0);
}
}
_previewImage.prototype.endAction = function(ts,te){
var imgStatus = this.getIndexImage();
var x0_offset = te.x0 - ts.x0;
var y0_offset = te.y0 - ts.y0;
var time = te.time - ts.time;
var slipTime = 0;
this.allowMove = false; //结束所有行为
if(ts.length==1){ //单手指(图片位移)
if(Math.abs(x0_offset)>10){ //防止误触关闭看图
event.preventDefault();
}
switch(this.statusY){
case 1:
imgStatus.y = this.allowY;
imgStatus.my = 0;
slipTime = this.slipTime;
break
case 2:
imgStatus.y = imgStatus.y+imgStatus.my;
imgStatus.my = 0;
break
}
switch(this.statusX){
case 1: //左滑->初始状态到达或超过右边界->图片平滑移动到达条件-切换下一图
if(this.index!=this.maxLen&&(x0_offset<=-this.imageChageNeedX||(time<200&&x0_offset<-30))){ //下一图
this.changeIndex(1);
}else{
this.changeIndex(0);
if(slipTime!=0){
this.translateScale(this.index,slipTime);
}
}
break
case 2: //右滑->初始状态到达或超过左边界->图片平滑移动到达条件-切换上一图
if(this.index!=0&&(x0_offset>=this.imageChageNeedX||(time<200&&x0_offset>30))){ //上一图
this.changeIndex(-1);
}else{
this.changeIndex(0);
if(slipTime!=0){
this.translateScale(this.index,slipTime);
}
}
break
case 3: //scale>1,初始状态未到边界->图片平滑移动未到边界
imgStatus.x = imgStatus.x+imgStatus.m;
imgStatus.m = 0;
this.translateScale(this.index,slipTime);
break
case 4: //scale>1,初始状态未到边界->图片平滑移动到边界->阻尼移动
imgStatus.x = this.allowX;
imgStatus.m = 0;
slipTime = this.slipTime;
this.translateScale(this.index,slipTime);
break
case 5: //scale=1,box位移，图片切换
if(x0_offset>=this.imageChageNeedX||(time<200&&x0_offset>30)){ //上一图
this.changeIndex(-1);
}else if(x0_offset<=-this.imageChageNeedX||(time<200&&x0_offset<-30)){ //下一图
this.changeIndex(1);
}else{
this.changeIndex(0);
}
break
case 6: //scale=1,长图片
imgStatus.y = imgStatus.y+imgStatus.my;
imgStatus.my = 0;
break
case 7: //scale=1,长图片 到边界
imgStatus.y = this.allowY;
imgStatus.my = 0;
this.translateScale(this.index,this.slipTime);
break
}
}else{ // 放大倍数问题
event.preventDefault();
var scale = imgStatus.scale*imgStatus.scalem;
var $img = this.getJqElem(this.index);
imgStatus.scale = scale;
var allow = this.getAllow(this.index);
if(imgStatus.x>allow.x){
slipTime = this.slipTime;
imgStatus.x = allow.x;
}else if(imgStatus.x<-allow.x){
slipTime = this.slipTime;
imgStatus.x = -allow.x;
}
if(imgStatus.y>allow.y0){
slipTime = this.slipTime;
imgStatus.y = allow.y0;
}else if(imgStatus.y<allow.y1){
slipTime = this.slipTime;
imgStatus.y = allow.y1;
}
if($img.height*imgStatus.scale<=this.winh){
imgStatus.y = 0;
}
if($img.width*imgStatus.scale<=this.winw){
imgStatus.x = 0;
}
imgStatus.scalem = 1;
if(scale>this.maxScale){ //倍数大于最大限制倍数
imgStatus.scale = this.maxScale;
slipTime = this.slipTime;
}else if(scale<1){//倍数小于1
this.imgStatusRewrite();
slipTime = this.slipTime;
}
if(slipTime!=0){
this.changeIndex(0);
this.translateScale(this.index,slipTime);
}
}
};
_previewImage.prototype.getAllow = function(index){
var $img = this.getJqElem(index);
var imgStatus = this.getIndexImage(index);
var allowX = Math.floor(($img.width*imgStatus.scale-this.winw)/(2*imgStatus.scale));
var allowY0,allowY1;
if($img.height*imgStatus.scale<=this.winh){
allowY0 = 0;
allowY1 = 0;
}else if($img.height<=this.winh){
allowY0 = Math.floor(($img.height*imgStatus.scale-this.winh)/(2*imgStatus.scale));
allowY1 = -allowY0;
}else{
allowY0 = Math.floor($img.height*(imgStatus.scale-1)/(2*imgStatus.scale));
allowY1 = -Math.floor(($img.height*(imgStatus.scale+1)-2*this.winh)/(2*imgStatus.scale));
}
return {
x:allowX,
y0:allowY0,
y1:allowY1,
};
};
_previewImage.prototype.getSlowlyNum = function(x,maxOver){
var maxOver = maxOver||this.winw*this.maxOverWidthPercent;
if(x<0){
x = -x;
return -(1-(x/(maxOver+x)))*x;
}else{
return (1-(x/(maxOver+x)))*x;
}
};
_previewImage.prototype.getScale = function(ts,tm){
var fingerRangeS = Math.sqrt(Math.pow((ts.x1 - ts.x0),2)+Math.pow((ts.y1-ts.y0),2)); //两手指的初始距离
var fingerRangeM = Math.sqrt(Math.pow((tm.x1 - tm.x0),2)+Math.pow((tm.y1-tm.y0),2)); //两手指移动过程中的距离
var range = fingerRangeM/fingerRangeS;
return range;
};
_previewImage.prototype.imgStatusRewrite = function(index){
var index = index===undefined?this.index:index;
var imgStatus = this.imgStatusCache[index];
imgStatus.x = 0;
imgStatus.y = 0;
imgStatus.m = 0;
imgStatus.my = 0;
imgStatus.scale = 1;
imgStatus.scalem = 1;
if(index!=this.index){
this.translateScale(index,this.slipTime);
}
}
_previewImage.prototype.changeIndex = function(x){
var imgStatus = this.getIndexImage();
var oldIndex = this.index;
var _this = this;
if(this.index==0&&x==-1){
this.index = this.index;
}else if(this.index==this.maxLen&&x==1){
this.index = this.index;
}else{
this.index+=x;
this.$text.innerHTML = ""+(this.index+1)+"/"+(this.maxLen+1); //当前第几张/图片总数
var hash = this.imgStatusCache[this.index].hash;
var imgCache = this.imgLoadCache[hash];
if(!imgCache.isload){ //图片未缓存则加载图片
imgCache.elem.src = this.urls[this.index];
imgCache.elem.onload = function(){
imgCache.elem.parentNode.className+=" previewImage-nobackground";
imgCache.isload = true;
}
}else{
imgCache.elem.parentNode.className+=" previewImage-nobackground";
}
}
this.box.x = -this.imageChageMoveX*this.index;
this.box.m = 0;
if(oldIndex!=this.index){
this.imgStatusRewrite(oldIndex);
}
this.translateScale(this.bIndex,this.slipTime);
}
_previewImage.prototype.getIndexImage = function(index){
var index = index==undefined?this.index:index;
return this.imgStatusCache[this.index];
}
_previewImage.prototype.translateScale = function (index,duration){
var imgStatus = this.imgStatusCache[index];
let $elem = this.getJqElem(index);
var scale = imgStatus.scale*imgStatus.scalem;
var offsetX = imgStatus.x+imgStatus.m;
var offsetY = imgStatus.y+imgStatus.my;
var tran_3d='scale3d('+scale+','+scale+',1) '+' translate3d(' + offsetX + 'px,' + offsetY + 'px,0px)';
// var tran_2d='scale('+scale+','+scale+') '+' translate(' + offsetX + 'px,' + offsetY +'px)';
var transition = 'transform '+duration+'s ease-out';
this.addCssPrefix($elem,'transition',transition);
this.addCssPrefix($elem,'transform',tran_3d);
}
_previewImage.prototype.getJqElem = function(index){
var $elem;
var index = index==undefined?this.index:index;
if(index<=this.maxLen){
var hash = this.imgStatusCache[index].hash;
var img = this.imgLoadCache[hash].elem;
$elem = img;
}else{
var elem = this.imgStatusCache[index].elem;
$elem = elem;
}
return $elem
}
/**
* [addCssPrefix 增加css前缀]
* @param {[elem]} elem [element]
* @param {[string]} prop [css attribute]
* @param {[string]} value [css value]
*/
_previewImage.prototype.addCssPrefix = function(elem,prop,value){ //可以优化todo
for(var i in this.cssprefix){
var cssprefix = this.cssprefix[i];
if(cssprefix===""){
prop = prop.toLowerCase();
}else{
var len = prop.length;
prop = prop.substr(0,1).toUpperCase()+prop.substr(1,len).toLowerCase()
}
if(document.body.style[prop]!==undefined){
elem.style[prop] = value;
return
}
}
}
_previewImage.prototype.getTouches = function(e){
var touches = event.touches.length>0?event.touches:event.changedTouches;
var obj = {touches:touches,length:touches.length};
obj.x0 = touches[0].pageX
obj.y0 = touches[0].pageY;
obj.time = new Date().getTime();
if(touches.length>=2){
obj.x1 = touches[0].pageX
obj.y1 = touches[1].pageY
}
return obj;
}
window.previewImage = new _previewImage();
// AMD loader
if ( typeof define === "function" && define.amd ) {
define([], function() {
return previewImage;
} );
}
return previewImage;
}));