monitoring events from an Event Structure

[bmihura]

I'd like to monitor most of the events from an Event Structure. The way I'm doing it now is clunky; I have a subVI in all of the events that uses the "CtrlRef" and "Type" inside each Event Structure case and creates a string that I append to a list on my front panel. For example, the list might say:

Slider, Value Changed
Numeric, Value Changed

Having a subVI in each case seems very awkward; is there a better way to monitor events from an Event Structure?

[Kenny_K]

You may want to check out the producer/consumer with events structure in the examples.

What are you using the String for??  (Slider, Value Changed)  What is the list for??  Just an indicator of what has been pressed??

I guess we would need some more information on what you are exactly trying to accomplish.

Kenny

[altenbach]

Well, if the same subVI is in all event cases, the subVI belongs outside the event structure. Now feed all the control references and type outputs from all the cases to a single output tunnel on the right boundary of the event structure, then to your subVI. 🙂

If some events don't have a control reference, place the subVI in a case structure and place a TRUE boolean in some of the event cases to decide if the subVI needs to execute. If the output tunnel is set to "use default if unwired", you only need a few TRUEs, while most cases don't need a boolean at all.

Message Edited by altenbach on 01-02-2007 08:54 AM

[bmihura]

Ooh, perfect reply <b>altenbach</b>.

I've attached a little demo in which I have no subVI (just to make it all one VI), and instead of using the Boolean you suggested, I allow the control reference to be invalid.

[altenbach]

Two small things: 🙂

1. I typically prefer a shift register to keep the event string. This eliminates all the local variables (see image).
2. "# of timeouts" should probably be called "# of iterations". All events will cause an increment.

Message Edited by altenbach on 01-02-2007 04:42 PM

[bmihura]

On item #1, when appending to a listlike string, I've always found a reference to said string to be most efficient; pass said reference to a subVI that appends then scrolls to the bottom, rather than my "append on top" concept. Your shift register idea is more true to form for the dataflow concept; that I like. Also, I would never actually use the local variable thing like I did in real life! That was just for simplicity of the demo.

On item #2, you're right. It should be "iterations", not "timeouts".

Thanks again for the initial hint, that got me out of my mental rut.