gistfile1.txt

//form.html
#{list items:_fields ?: currentType.fields*.name, as:'fieldName'}
%{x++}%
<div id="${x}" style="height: 20px;">
</div>
<script type="text/javascript">
$(document).ready(function() {
    $('#${x}').load('@{CRUD.loadField(fieldName)}');
});
</script>
#{/list}


//crud.java
    public static void loadField(String id, String field) {
        ObjectType type = ObjectType.get(getControllerClass());
        notFoundIfNull(type);
        Object object = SienaModelUtils.findById(type.entityClass, id);
        Object field = object.getClass().getField(field).get(object);
        render("CRUD/field.html", field);
    }