title: How to ensure if atleast one checkbox is selected for multiselect jQuery plugin
body: <p>I am using the jquery multiselect <a href="http://www.erichynds.com/jquery/jquery-ui-multiselect-widget/" rel="nofollow">plugin</a>.  Right now I am checking if the user has selected any checkbox or not with the below code.</p>
  
  <pre><code>function fntemp()
  {
  var values = $("select").val();
  alert(values);
  if(!values){
  alert("Please select atleast one value from the dropdown.");    
   }
  }
  </code></pre>
  
  <p>But this does not work when we click "Check All" link. Any suggestions?</p>