/*!
* 2012-01-13 v1.1 偏移值计算修改 position → offset
* 2012-09-25 v1.2 增加滚动容器参数, 回调参数
* 2015-11-17 v1.3 只对显示元素进行处理
*/
(function($) {
$.fn.scrollLoading = function(options) {
var defaults = {
attr: "data-url",
container: $(window),
callback: $.noop
};
var params = $.extend({}, defaults, options || {});
params.cache = [];
$(this).each(function() {
var node = this.nodeName.toLowerCase(), url = $(this).attr(params["attr"]);
//重组
var data = {
obj: $(this),
tag: node,
url: url
};
params.cache.push(data);
});
var callback = function(call) {
if ($.isFunction(params.callback)) {
params.callback.call(call.get(0));
}
};
//动态显示数据
var loading = function() {
var contHeight = params.container.height();
if ($(window).get(0) === window) {
contop = $(window).scrollTop();
} else {
contop = params.container.offset().top;
}
$.each(params.cache, function(i, data) {
var o = data.obj, tag = data.tag, url = data.url, post, posb;
if (o) {
post = o.offset().top - contop, post + o.height();
if (o.is(':visible') && (post >= 0 && post < contHeight) || (posb > 0 && posb <= contHeight)) {
if (url) {
//在浏览器窗口内
if (tag === "img") {
//图片,改变src
callback(o.attr("src", url));
} else {
o.load(url, {}, function() {
callback(o);
});
}
} else {
// 无地址,直接触发回调
callback(o);
}
data.obj = null;
}
}
});
};
//事件触发
//加载完毕即执行
loading();
//滚动执行
params.container.bind("scroll", loading);
};
})(jQuery);
//实例
<script>
var tempHTML = "";
for (var i=1; i<=30; i+=1) {
if (i == 6) {
tempHTML += '<div class="zxx_test_list scrollLoading" data-url="loaded.html"><div style="padding:100px 0; text-align:center;"><img src="/study/image/loading.gif" style="margin:0 8px -8px 0;" />加载中...</div></div>';
} else {
tempHTML += '<div class="zxx_test_list tc"><img class="scrollLoading" data-url="//image.zhangxinxu.com/image/study/head/s180/'+i+'.jpeg" src="//s1.xiaomishu.com/b/img/pixel.gif" width="180" height="180" style="background:url(/study/image/loading.gif) no-repeat center;" /><br />图片'+i+'(新浪微博提供)</div>';
}
}
tempHTML += '<div class="zxx_test_list tc"><h6>下面藏了一张图片,<a href="javascript:" id="zxxClickBtn">点击显示</a></h6>\
<div id="zxxShow" style="display:none;">\
<img class="scrollLoading" width="256" height="191" data-url="//image.zhangxinxu.com/image/study/s/s256/mm1.jpg" />\
</div></div>';
document.getElementById("zxxMainCon").innerHTML = tempHTML;
</script>
<script>
$(function() {
$(".scrollLoading").scrollLoading({
container: $("#zxxMainCon"),
callback: function() {
this.style.border = "3px solid #a0b3d6";
}
});
//$(".scrollLoading").scrollLoading();
});
</script>