Refresh a running presentation changed by UNO

I’m trying to turn LibreOffice Impress into a Raspberry Pi digital signage tool. My plan is to write a small web application on the Pi that I can upload new presentations to, and then use the UNO SDK to start the newly updated presentation over the existing one, and close the old one down.

Since these presentations may be long running, and everyone seems to want to know what time it is, I’d like to have the application look for a special Shape in the presentation with a special piece of text, say, “=time” and replace it with the current time.

I’ve been able to do this in a presentation using UNO and Python, but even though the document is updated, the slides are not updated, regardless of if it’s the active slide. Is there any way to get a running presentation to refresh the slides without closing and reopening it?

The short answer is no.

Unfortunately there is no way to do that. A bug was filed in 2011 in the Bugzilla asking for this feature, but it has not been updated since June of 2016. See this link: https://bugs.documentfoundation.org/show_bug.cgi?id=34965 for the bug. There is also a $25 bounty for whoever adds this feature available on Freedom Sponsors, here: https://freedomsponsors.org/issue/173/make-impress-slides-editable-during-presentation#sponsors.