Re: Any way to tell when an image display has been updated?
My kludge/workaround is to add a variable delay before the message is cleared. The delay is based on the image size and some empirically-derived constants. The issue is that the terminals and locals of controls schedule an update and allow for batching. They are not synchronous. To synchronize things to them, you can try to use the Value Property on the control's property node. At the moment I believe this is synchronized. If not, you can use the Panel's property called Defer Panel Updates. You can use the to synchronize multiple property nodes and values by setting to TRUE, modifying, then setting defer to FALSE. So, you can set your Boolean or string telling the user an update is in progress, then defer, then set the image and string/Boolean again, then defer to FALSE. The string/Boolean and image should update at close to the same time telling the user that the update is finished. Greg McKaskle
Re: Any way to tell when an image display has been updated?
How about a sequence like this: 1. Set cursor to busy (wait glass) 2. Update display 3. Reset cursor George Zou http://gtoolbox.yeah.net
Re: Any way to tell when an image display has been updated?
Maybe a little bit off topic, but I remember there was a (set) VI(s) in the internet toolkit which help you to detech if there are any image (png or other type) updates. To synchronize the data and graph update, you can move or hide/show the graph everytime after each data update, so labview is 'forced' to update the indicator with latest data. -Joe
Re: Any way to tell when an image display has been updated?
I've already tried something like this and it just does not work like I want it to. Enforced with a sequence structure I do this: 1) put up a message saying Updating 2) dump the updated data to the display 3) clear the message What I see on the CRT is this: 1) a message saying Updating 2) the message quickly goes away 3) several seconds later the image changes. My kludge/workaround is to add a variable delay before the message is cleared. The delay is based on the image size and some empirically-derived constants.
Re: Any way to tell when an image display has been updated?
Thanks for the reply, but moving the image or blanking it out prior to displaying it won't work for us because we are looking for possible subtle changes between subsequent images and doing this would make that difficult (and it would also tend to introduce a considerable delay in the update).
Re: Any way to tell when an image display has been updated?
Thanks for the reply but unfortunately this proposed solution does not see the delay within the display system. For large images (4kx4k) the time it takes to update the CRT display can be quite long and it seems that this time is invisible to LabVIEW. It can leave the user sitting there wondering Well has it or hasn't it updated yet? if there isn't much difference expected between the old and new images...
