title: KnockoutJS - Can we have Observable Function call for CSS updates
body: <p>I have a ticketing system which is written in KnockOut using template. Template structure is as below This template is repeated for multiple users on a page. In this parent.AssignedTickets is a list of Ticket Id assigned to users.</p>
  
  <pre><code>&lt;script type="text/html" id="TicketAssignmentTemplate"&gt;
  &lt;td&gt;
     &lt;label data-bind="css: {success: $root.getCheckStatus(TicketId, $root.AllAssignedTickets)}"&gt;
        &lt;input type="checkbox" data-bind="checkedValue: TicketId, checked: $parent.AssignedTickets" /&gt;
      &lt;/label&gt;
  &lt;/td&gt;
  &lt;td&gt;
      &lt;label data-bind="text: title"&gt;&lt;/label&gt;
  &lt;/td&gt;
  self.getCheckStatus = function (itkID, ListID ) {
      if (ListID.indexOf(itkID)&gt;= 0)  
         return true;
      else 
         return false;
  }
  </code></pre>
  
  <p></p>
  
  <pre><code>&lt;style&gt;.success{background-color: #DFF0D8;}&lt;/style&gt;
  </code></pre>
  
  <p>So system has multiple TicketIDs and if it is assigned to user by checking the check box, parent.AssignedTickets gets updated and I update root.AllAssignedTickets, both of which are observable arrays. Now I want to change label color of checkbox which gets updated by getCheckStatus(TicketId, $root.AllAssignedTickets).</p>
  
  <p>Can the function be made observable to update CSS real time when checkbox is checked or unchecked?</p>