Javascript: Freeze/Lock Web Page While Loading

I would like my web page could be freeze/locked when processing, and users are unable to click any button. Here is a excellent JavaScript library - Impromptu .

 
 var v;
 
 function trigger()
 {
  var txt = 'Processing';
  v = $.prompt(txt, {
   opacity: 0.8
  });
  execute();
 }
 
 function execute()
 {
  //execute your code
  $.prompt.close();
 }

It works perfect on Chrome and IE.