title: jQuery disable button (NOT Submit) until field validates + Validation Plugin
body: <p>I have 4 buttons on my form, a Submit, Cancel, Add and Remove button. All are working as expected but I would like to disable the Add button until the input field validates. I'm using the Validation plug-in and I think this can be done with a required validation with a callback but I'm not sure.</p>
  
  <p>Could someone point me in the right direction?</p>
  
  <p>UPDATE:</p>
  
  <p>Here is an idea of some code </p>
  
  <pre><code>required: function(element) { 
     return($('#chargeamtaddButton').attr('disabled', ? '','disabled');
  }
  </code></pre>
  
  <p>Looking for that true/false option flag to set the disabled attribute</p>