How can we built dynamic sub template URL in main template@BI Publisher reports

Hi Friends,

Thanks for looking at my post!!

I have a challange to get below requirement to complete,would appriciate if you can provide your inputs for that.

We have entity which has attachment,we need to print the attachment with continuously to the existing report(i.e when click on button it opens report,not as an attachment in email).Then i have decided to use sub template concept but the problem is attachment name will change every time,i'll get the file name in xml tag and add the file name at end of sub template URL.

<?variable@incontext:vTestdoc;.//Testdoc?> <?variable@incontext:vTestflg;xdoxslt:ifelse($vTestdoc!='',concat($vTestdoc,'.rtf'), '')?>  <?$vTestflg?>