JavaScript implements waterfall flow effect of automatic image loading

Let me show you the renderings first:

Pictures can be automatically loaded and displayed when you slide down the web page.

The box model for holding pictures is as follows:

　　　　<div class="box">
<div class="box_img">
<img src="Img/8.jpg">
</div>
</div>

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Set img-width to 150px, then add padding and shadow effects to box_img, set the outer margin of box to 0, and add padding. The width of the box is stretched by img-width and margins. That is to say, there is no spacing between the boxes, but there is some margin effect inside the box. In this way, there is no need to consider the margin issue when setting the position in js, and just call the width of the box directly.

Set the position of the div holding all the boxes to relative, so that when setting the top value or left value, you don’t need to consider the outermost margin attribute.

Place the picture: Get the height of the first row of pictures and store them in the array. Set the position of the next pictures to absolute and place them below the picture with the smallest height. Then set top and left, and minimize the array. value plus the height of the newly placed image. That is to say, except for the first row of pictures originally placed in HTML, all other pictures are repositioned in js.

When the page is slid to the bottom, the event function is triggered, and then some pictures are placed to ensure unlimited loading of pictures.

　HTML file:

<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-">
<title></title>
<link rel="stylesheet" href="waterfall.css" type="text/css">
<script src="waterfall.js"></script>
</head>
<body>
<div id="content">
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box" >
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box" >
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box" >
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box" >
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box">
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
<div class="box" >
<div class="box_img">
<img src="Img/.jpg">
</div>
</div>
</div>
</body>
</html>

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CSS file:

*{
margin: ;
padding:;
}
#content{
position: relative;
background-color: #;
}
.box{
padding: px;
float: left;
}
.box_img{
padding: px;
border: px solid #cccccc;
box-shadow: px #cccccc;
border-radius: px;
}
img{
width: px;
height: auto;
}

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js file:

The Math.floor() function can round down.

Math.min.apply(null,heightArr); The function can obtain the minimum value of the heightArr array.

Window.onscroll=function(){}; This function is triggered when the page is scrolled.

　document.documentElement.clientHeight; the height displayed by the browser.

　document.documentElement.scrollTop; sliding distance.

/**
* Created by asua on 2016/4/9.
*/
window.onload=function(){
imgLocation("content","box");
var lodeImage={"Date":[{"src":"1.jpg"},{"src":"2.jpg"},{"src":"3.jpg"},{"src":"4.jpg"},{"src":"5.jpg"},{"src":"6.jpg"},{"src":"7.jpg"},{"src":"8.jpg"},{"src":"9.jpg"},{"src":"10.jpg"},]}
window.onscroll=function(){
if(checkFlag()){
for(var i=0;i<lodeImage.Date.length;i++){
var box=document.createElement("div");
box.className="box";
var cparent=document.getElementById("content");
cparent.appendChild(box);
var box_img=document.createElement("div");
box_img.className="box_img";
box.appendChild(box_img);
var img=document.createElement("img");
img.src="Img/"+lodeImage.Date[i].src;
box_img.appendChild(img);
}
imgLocation("content","box");
}
}
}
function checkFlag(){
var cparent=document.getElementById("content");
var ccontent=getChildElement(cparent,"box");
var lastContentHeight=ccontent[ccontent.length-1].offsetTop;
var scrollHeight=document.documentElement.scrollTop||document.body.scrollTop;
var pageHeight=document.documentElement.clientHeight||document.body.clientHeight;
console.log(lastContentHeight+":"+scrollHeight+":"+pageHeight);
if(lastContentHeight<scrollHeight+pageHeight){
return true;
}
}
function imgLocation(parent,child){
var cparent=document.getElementById(parent);
var ccontent=getChildElement(cparent,child);
var imgwidth=ccontent[0].offsetWidth;
var cols=Math.floor(document.documentElement.clientWidth/imgwidth);
cparent.style.cssText="width:"+imgwidth*cols+"px;margin:30px auto";
var heightArr=[];
for(var i=0;i<ccontent.length;i++){
if(i<cols){
heightArr.push(ccontent[i].offsetHeight);
}else{
var minHeight=Math.min.apply(null,heightArr);
var minIndex=getMinIndex(heightArr,minHeight);
ccontent[i].style.position="absolute";
ccontent[i].style.top=minHeight+"px";
ccontent[i].style.left=ccontent[minIndex].offsetLeft+"px";
heightArr[minIndex]+=ccontent[i].offsetHeight;
}
}
}
function getMinIndex(heightArr,minHeight){
for(var i=0;i<heightArr.length;i++){
if(heightArr[i]==minHeight){
return i;
}
}
}
function getChildElement(parent,content){
var contentArr=[];
var allcontent=parent.getElementsByTagName("*");
for(var i=0;i<allcontent.length;i++){
if(allcontent[i].className==content){
contentArr.push(allcontent[i]);
}
}
return contentArr;
}

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Okay, this is the introduction to the waterfall flow effect code for automatic image loading using js. I hope it will be helpful to you!