Front Panel doesn't display if VI is called from a Webservice

[Yakov]

Hi,

I'm trying to call a VI that would show it's front panel by a labview webservice.

It works on a debug web server, but it doesn't work when I publish the webservice.

Here is an example:

When "VI with UI.vi" is running it writes to a log file that it's "Execution:Show Front Panel On Call"  is True and "Front Panel Window:State" is Standard. So, it thinks, that front panel should be shown and that it is shown.

Even if I load "VI with UI.vi" dynamically and tell it explicitly to show it's front panel it behaves the same.

Is there a way to display a front panel out of webservice?

[Yakov]

Hi,

I'm adding a code sample that demonstrates the problem.

[FireFist-Redhawk]

What exactly are you trying to get out of using the Web Service? Are you trying to have it set up to where any computer on network can log on to the web service and open the VI?

[Yakov]

We have a huge LabView application. We are re-implementing UI so it runs out of a browser using React JS and Java back-end. LabView application becomes a library that is interfaced by api calls to webservices. Eventually the library and webservices interfacing it will run on a server. Meanwhile, some of more complex LabView front panels stay in LabView. So, webservices will run locally and invoke those VIs that have not yet been re-implemented in JS.

[AllisonSCJ]

I was unable to get your attached snippet to work to get more information on what you're trying to accomplish. I would strongly recommend checking NI's Examples under WebService; the AddressBook example should help you.

Labview's webservice seems to have two separate examples: in one, the Web Service is launched with pre-made html pages for the UI, and Labview vis work only as backend programming.

In another version, called weather monitor, the content of the vi is converted to an image and imported into a web page that way. 

You can also enable vi front panel publishing using the following help guide here.