[oXygen-sdk] Resolving of custom attribute through a custom URLHandler

Hi I have a custom attribute defined in my DITA customization called 'varref'. Whenever an element has this attribute set the content of this element needs to be looked up in another document and inserted (like a conref in DITA). For conref resolving I'm using a custom URLHandler. Is there a way to do resolving of my custom attribute (like conref resolving) through the oXygen api? Thanks in advance Jan Bevers | Developer | SDL | Content Management Technologies Division | +32 (0)15 400 970 | jbevers@sdl.com