Callbacks not working in LabVIEW executable front panel

[fgregory]

I have a couple of callbacks in the process model that trigger an event in the event structure to update front panel indicators for the user. It all works great until I build an executable. This might also be an indication of other items I have not discovered yet as well.

Any ideas?

Thanks for the help everyone.

[Kelly_R]

Hi fgregory,

Can you give me a little bit more information about your set up?  Which version of TestStand are you using?  What did you develop your user interface in?  Did you modify one of our examples OIs, and if so, which one?  Are you running this on the development machine or the deployment machine?  Which callbacks did you override?  Also, can you give more information about how you are passing the event references to your user interface?

[fgregory]

Hello,

Well as the subject implies the user interface front panel is built in LabVIEW. I am using TestStand 4.2 and I am currently running on the development machine. I can run the LabVIEW front panel executing sequence files in the development environment fine and then when running in an executable, my callbacks don't work. I am passing a reference to the "event" into the callback vi and I am using the usermessagebase + 1, 2, and 8 to send the callbacks. I thought my first step would be to build the executable with the ability to see the wiring diagram and watch the callback vi to see if it executes, however, I am having trouble getting the diagram to show up.

Thoughts?

Thanks again. 

[Kelly_R]

Hi Gregory,

What I would like you to try is to place a message pop-up VI in your callback VI to verify whether or not we are actually getting into the VI.  If we are, there is most likely some issue with a portion of your code being executed in that VI.  If it is possible, you can post a screenshot of this for us to take a look at.  If we do not execute the callback VI, then we will need more information to diagnose what is going on.  What I would like to you to do if this is the case is to post simple files that can reproduce this issue, so we can debug here on our end.  Also, I had meant to ask in the last post, what version of LabVIEW are you working with?

[fgregory · Accepted solution]

Found It!

Not unlike most LabVIEW developers I have a pallet of utility vis that I use over and over. One such vi is a vi uses a property node to find out what environment the app is running in, i.e. .llb, exe, development, student edition, etc. This vi is used because referencing vis in an executable have a different path than when referencing them in the development environment. Using this vi allows for your code to reference the vis properly when developing and when the executable gets built. The code still works because it automatically adjusts the path to the referenced vi. See "Environment Path Finder.vi" attachment.

Now for the fun part! For some reason, maybe because of the funloving nature of NI and the relationship it has with its developers :-), NI decided to change the path of executables in LabVIEW 2009. After hours of troubleshooting and countless re-builds, I had come to the conclusion that the "Strip Paths" function just magically stopped working. It was at that point that a friend of mine happened to walk by and ask why I was about to through my monitor across the room(figuratively speaking of course, I am sure we have all been there). I explained what could be the only conclusion, strip paths don't work!

My friend immediately started laughing, having recently had the same issue. He explained that in LabVIEW 2009 the executable paths are different and that our "find path vi" would not work. He went on to say that NI, after finding this humorous, did however give the developers a way to fix this issue with a check a box in the app builder. The checkbox is called"Use LabVIEW 8.x file layout." See attached pic named "App Builder."

The only thing I could say to my friend was, "silly me, I should have known what that."

LOL

Thanks for trying to help, this one kicked my butt.