如何给一个嵌入页面的pdf加上加载进度条，等待条也可以，加载完成后直接播放pdf？

<script>
function load(){document.body.removeChild(document.getElementById('load'));}
</script>
<div id="load" style="width: 100px; height: 100px; z-index: 100; position: fixed; margin: 50px auto auto -50px; top: 50%; left: 50%;">加载中....</div>
<iframe onload="load()" src="http://www.pdfobject.com/pdf/pdfobject.pdf#view=FitH&amp;pagemode=thumbs&search=pdfobject&toolbar=0&statusbar=0&messages=0&navpanes=1" type="application/pdf" width="100%" height="100%"></iframe>