Image on Sitemap not updating in App but Ok in Webpage

Environment:
RPI Model 3B - Running Stretch
openHAB 2.5.6-2 (Release Build)
openJDK “1.8.0_252”
openHAB Android App version 2.13.0

I have a site map that has an image from MotionEye OS displayed to represent the last picture taken when the motion was detected. I’d followed some example in a thread which I can’t find for the life of me now.

Anyhow I’ve noticed that if I access Basic UI using a web browser the Image shown is indeed the Latest one but I use the openHAB app on my phone or tablet the image displayed is actually the very first one that was loaded when the page on the sitemap was first accessed.

In other words there must be some caching somewhere that is not replacing the image in the App.
The Camera Rule does this…

        val url = "http://<IP>:<port>/picture/2/current"
        val outputfile = "/srv/openhab2-conf/html/" + "snapshot.jpg"
        var cmd = "curl -m 10 -o " + outputfile + " " + url
        executeCommandLine(cmd)

The Sitemap displays the Image thus

Image url="http://localhost:8080/static/snapshot.jpg"

There are no errors coming up in the Log Viewer, and the image in \conf\html\snapshot.jpg is the latest

Ok so I realised from some other threads I didn’t have a refresh=xxxxx at the end of the url
When I added this the App images updated.

So this is solved but I’d like to understand what the refresh is for and what the number after is i.e ms or seconds

It’s milliseconds. See the docs: https://www.openhab.org/docs/configuration/sitemaps.html#element-type-image

Doh!! Thanks. I didn’t think it was opebHab and was looking at HTML documentation