xsl:import and xsl:include do not show changes from the xsl file in custom display forms

Question

I have been struggling to edit all my custom display forms and view forms to render using external xsl files. So far I found out that normal ways cited around the internet do not work very smoothly for my view forms, but I managed to find a workaround for them (I only use xsl:include and link to a file which is in the default /_layouts/xsl/ folder).

So now I am trying to fix the display forms. I have created a custom display form for a particular content type; then I use xsl:include (or xsl:import) and link the external xsl file (which is already in the /_layouts/xsl/ folder). I also delete any custom xsl templates from within the custom display form, so that I am sure it will render my custom xsl file.

After all this, the fields render as expected in SPDesigner and in IE, but when I go and make edits to the linked xsl file (from the server) it doesn't update my changes neither in SPD, nor in IE. It updates the fields only if I go and edit the xsl include/import tag (I edit it with the same xsl link - so I don't make any actual changes) and then I save the custom display form.

I tried also with the xsl link - same result - it will show the updated xsl file only if I go to the xsl link property of the web part, click in it, and save the web part.

Do you have any ideas what I might be doing wrong?

Edit: I just noticed that the views also don't update correctly. If I update the file from the server, nothing gets updated on the view. If I go and save the view (without making any changes to it) then the update from the server shows. I can also make 1 more update on the server xsl file and it will be displayed. Further changes to the server xsl do not display and I need to open the view from SPD and 'save' it again to show the updates. Is there any caching logic for included xsl files?

Answer 1

I'll answer my own question:

I couldn't make my views and display forms work with xsl:import, so I had to use xsl:include. Xsl:include caches the included xsl and does not refresh when the included xsl file is changed - this is by design as explained in this thread. So after all I couldn't use it.

I resolved my issue by using 'xsl link' property for the web parts of views and display forms. For display forms I had to disable caching to make sure it picks changes made to the linked xsl. Once I was done with the editing I enabled caching again for performance reasons.