Event Queue Deadlock Error

[BevP]

LabVIEW 7.1, PDA Module for Palm OS (long-time LV programmer, new to PDA module)

I am writing an app that displays a main screen of choices via Boolean button controls.  An Event structure is used to detect ValueChange in the Booleans.  When a button is clicked, a sub-vi is called that opens the sub-vi's front panel that has data display and a couple of buttons that are also processed by an event structure.  I got a "event queue deadlocked" error message when testing.  Does this application structure violate the "single event structure in a loop" rule, even though one queue is in a sub-vi?  Must I use a state machine or some other architecture to make this work?

Thanks,

BevP

[tst]

Since only one VI can be displayed at a time, I guess opening a subVI within a frame locks the "FP" so you can't do anything. I do seem to recall doing this, however, so I suggest you try unchecking "Lock Front Panel...".

[Trevor]

I'm curious as to whether you solved your problem or not and if so whether you'd be willing to share your insight as I'm developing an application that will likely have similar issues.

I'm a long time LabWindows/CVI programmer, new to LabVIEW and PDA module that is trying to make the leap from C to G... not always easy.

Thanks,
Trevor

[fandres17]

A lot of time has passed but now I find the same problem and I have the solution.

If you have an event structure you MUST show the control and indicators involved in the cases in the front panel and in the monitor of your PDA/Touchscreen device, because oterwise the event queue deadlocked error appears.

It makes sense becasuse if you do not show them; you will never be able to call events and the aplication is going to stuck.