jquery - 加载html，然后在Jquery中使用Ajax加载图像

Question

基本上我在这里寻找的是性能。

$.post(link,     
  function(data){
         //removes the image that was displayed while loading
         $("#loadingImg").remove();

         //append the new content, into the content div
         //and add a div around the new content in order to lazy load
         $("#content").append('<div id="new-page">' + data + '</div>');
         //lazy load the images inside the new div
         $("#new-page").find("img").lazyload({ 
                 placeholder : "/images/white.png", effect : "fadeIn" });
  });

我想使用jquery插件，lazy load ，延迟加载附加到某些内容的图像。现在我可以看出，使用和不使用该代码的延迟加载行的加载时间完全相同(加载大约 20 个图像)。我现在假设 $("#content").append() 行在附加之前等待所有图像加载。

有什么方法可以将 html 放入页面中，阻止浏览器加载该 html 中的图像，然后在用户滚动时加载它们？

顺便说一句，即使我这样做:

data = '<div id="new-page-' + pageCounter + '">' + data + '</div>';
var newData = $(data);
newData.find("img").lazyload({ placeholder : "/images/white.png", effect : "fadeIn" });
$("#content").append(newData);

加载时间仍然相同...

感谢您的帮助!

Answer 1

Is there any way to put the html in the page, halt the browser from loading the images in that html, and then load them as the user scrolls?

是的，就是:jQuery 路径点: http://imakewebthings.github.com/jquery-waypoints/

工作示例:

http://jsfiddle.net/marcosfromero/BbA9M/

HTML:

<img id="first" src="" width="364" height="126" deferred="http://www.google.com/images/logos/ps_logo2.png" />

<div style="height: 500px; ">Some vertical space. Scroll to the bottom</div>

<img id="second" src="" width="364" height="126" deferred="http://www.google.com/images/logos/ps_logo2.png" />

我在此 HTML 代码中发现的唯一缺点是 deferred 属性不是标准的。

jQuery:

$('img').waypoint(function(event, direction) {
    // set the image src attribute from the deferred one, which has the real URL
    this.src = this.getAttribute('deferred');
}, {
    triggerOnce: true, // load the image just once
    offset: function() {
        // calculate where the event should be fired
        // in this case, when the whole image is visible
        return $.waypoints('viewportHeight') - $(this).height();
        // if you want to load the image when the top of it is visible change it for
        // return $.waypoints('viewportHeight');
    }
})