VI Templates and Remote Panels

[David Moerman]

My system creates multiple test windows using a dynamic load of a VI template, and I wish to have Remote Panel access to each of these test windows. The user does not need to instantiate the windows remotely, only access them. So, when each window is created, it creates it's own HTML file so a user can access it. It worked just great for .snap publishing -- so far, so good.

However, my VI template is a little unusual, because within it there are other VI-template subVIs. I do this because I make use of LV2 global variables (acts as a passive G object with it's own data space), and each window has it's own local copy of that template subVI.

Now when I try to access the Remote Panel on my instantiated test window, I get an error like this "The VI named 'Test Window 1.vi' contains unsaved untitled subVIs. Cannot save the VI before all its untitled subVIs are committed to the disk'. This error indicates that my template-subVI instantiations need to be saved in order for the Remote Panel to work. I'm not sure why this is a requirement, but let's go along with it for now.

So I went ahead and used a VI server method to save the untitled subVI instantiations to a temporary directory, with the intention of deleting them when the test window is closed. It worked! Kind of... it worked in development mode, but didn't work when I built the executable. The executable gives me error 1043: "Not supported in this version" when it tries to save the untitled subVIs (even though I specify to save WITHOUT the block diagram, which obviously isn't there).

Is there a way out of this quandry?

Thanks for your help,

David Moerman
TruView Technology Integration Ltd.

[Johnner]

The Remarks section of the online help for the Save Instrument method indicates that it is not available in the run-time engine, so it makes sense that you would receive an error, regardless what save options you choose.

Do you have a pared-down set of VIs that demonstrates the problem, so that others can more easily play around and try to think of a solution?

Regards,
John

[David Moerman]

OK, here it is... about as pared down as I can make it. I also included the build file, but the path will have to change when you try to build it of course. Note that all VI templates (even subVIs) need to keep their front panel when they get compiled.

So, if anyone out there can get the Remote Panel going with the executable, I will be both surprised and impressed. I've given up.

Thanks!

-Dave

[David Moerman]

Hello again everybody,

Sorry I have to re-submit my post. I found a bug in my demo (where the VI name referenced in the HTML did not match the running window). Also, I made it to dynamically set up the web server path, to make it easier on you.

BTW, this is in LV 7.0. And a warning: this problem is not for the faint-of-heart. I somewhat doubt there is a solution without NI changing how Remote Panels works.

Again, my apologies for the previous bug.

-Dave

[Johnner]

Dave,

OK, with appropriate HTML tweaks to specify my newer run-time engine, I see the same behavior that you describe under LabVIEW 7.1.1. ('Cannot save the VI before all its untitled subVIs are committed to the disk')

You get the same message if you try to connect to the panel from another LabVIEW development system (Operate >> Connect to Remote Panel...), so at least this isn't a specific limitation of the Web browser interface. It would be interesting to have an super-expert or an NI developer explain why these VIs ostensibly need to go through a save operation when they are accessed via remote panel. Maybe JPD can turn his new lightbulb icon on the problem...

--John