瀑布流JavaScript

最近跟着视频学习如何用javascript实现瀑布流效果。

下面是waterfall.js的源代码

window.onload=function(){
waterfall("container","box");
var imgData={"data":[{"src":"1.jpg"},{"src":"2.jpg"},{"src":"3.jpg"},{"src":"4.jpg"},{"src":"5.jpg"},{"src":"6.jpg"},{"src":"7.jpg"}]};
window.onscroll=function(){
if(checkFlag()){
var cparent=document.getElementById("container");
for(var i=0;i<imgData.data.length;i++){
var ccontent=document.createElement("div");
ccontent.className="box";
cparent.appendChild(ccontent);
var boximg=document.createElement("div");
boximg.className="box_img";
ccontent.appendChild(boximg);
var img=document.createElement("img");
img.src="img/"+imgData.data[i].src;
boximg.appendChild(img);
}
waterfall("container","box");
}

}
}

function checkFlag(){
var cparent=document.getElementById("container");
var ccontent=getChildElement(cparent,"box");
var lastContentHeight=ccontent[ccontent.length-1].offsetTop;
var scrolltop=document.documentElement.scrollTop ||document.body.scrollTop;
var pageHeight=document.documentElement.clientHeight||document.body.clientHeight;
if(lastContentHeight<scrolltop+pageHeight){
return true;
}
}

function waterfall(parent,content){
var cparent=document.getElementById(parent);
var ccontent=getChildElement(cparent,content);
var imgWidth=ccontent[0].offsetWidth;
var num=Math.floor(document.documentElement.clientWidth/imgWidth);
cparent.style.cssText="width:"+imgWidth*num+"px;margin:0 auto";

var boxHeightArr=[];
for(var i=0;i<ccontent.length;i++){
if(i<num){
boxHeightArr[i]=ccontent[i].offsetHeight;
}else{
var minHeight=Math.min.apply(null,boxHeightArr);
var minIndex=getminheightLocation(boxHeightArr,minHeight);
ccontent[i].style.position="absolute";
ccontent[i].style.top=minHeight+"px";
ccontent[i].style.left=ccontent[minIndex].offsetLeft+"px";
boxHeightArr[minIndex]=boxHeightArr[minIndex]+ccontent[i].offsetHeight;
}
}
}
function getminheightLocation(boxHeightArr,minHeight){
for(var i in boxHeightArr){
if(boxHeightArr[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;
}