General User Interface Data Flow Problem (LabVIEW 2012)

[dkw-info]

I am having problems reading & checking user input to a tabbed panel (see the tab "Test Parameters" in the attached example).

In essence I need to set and test many parameters.

In the example I need to create a binary mask from four select switches. On its own the scheme works a treat but in the context of

the tabbed panel the switches are never "reached". I tried to put a while structure around the switches (which works ex-vivo,

see attached "channelselect.vi") but the switches are never reached when I step through the code. Basically, I do not want to

leave the pane until all parameters have been set and verifyied.

I tried case structures (by group), flat structures (group by frame), Event Structures (event by nutton change)

I anticipate the same problems with the other sets of parameters. I need to change - set - check, in any order.

Understand the "setting" mechanism is tied to a sub-vi/class method where the parameter is tested, set and verified.

This is a long winded approach to ask the basic question "how would you lay it out"? I am sure this is a basic misunderstanding

on my part of the dataflow paradigm. I am not looking for anyone to do my work for me but I am looking to understand how this

works so I can get on with my day. 

Thanks in advance for any help you can proffer.

[crossrulz]

Do not use a Tab Value Changed Event.  Use the switch value change events.

You also do not need the wait in your loop.  The Event Structure will cause the idle while waiting for the user to press buttons and what not.

[dkw-info]

Thank you for the rapid reply.

I wonder however, how do you present only the front panel information to the user needed for that operation?

Do you mean use an "Event Structure"? With a "Case Structure" inside? How do I present choices to the user?

I see how to assign events to the Event Structure, but what object would I use to control the case? With my

limited knowledge I can't see how to make this work, that is why I used the tab value.

[crossrulz · Accepted solution]

You can still have the tab control.  You just don't need to do all of your processing when the user changes the tab.  You can make event cases on the button presses as well.  Treat the VI as an entire VI, not individual tabs that you have to manage.

[dkw-info]

Thanks again for the quick reply. I appreciate the reasons now for changing as you described.

David