Problem about asynchronous call: subVI front panel doesn't pop up when called.

Dear All,
I'm new to LabVIEW, and this is the first time I try to use the asynchronous call.
I'm using LabVIEW 2011.
I want to build a directory for several VIs, and it should allow users to open more than one of the VIs at the same time by pushing the buttons. Before building this directory, I simply tried to use asynchronous call to call a VI form another VI, but found a big problem.
I followed the steps in the help file, created a strictly typed reference, set the option to x80 because I don't need the return. When I run it for the first time, it worked fine: the subVI popped up and run. Then I closed the subVI. But for the sencond time and on, when I run the caller VI, the subVI didn't pop up, instead it seemed to run silently on background because when I manually opened it from the file I found it running. Besides, I didn't find any option like "show front panel when called" of the asynchronous call.
The caller VI and subVI are attached. The address of subVI in caller VI should be changed accordingly.
What should I do to make it work properly? Thanks very much for any idea!
Solved!
Go to Solution.
Attachments:
asynchronous_call.vi ‏8 KB
boolean.vi ‏7 KB

Jeff·Þ·Bohrer wrote:
A better approach is to set the vi properties programaticly like this:
Jeff, you will be happy to know that I used this tactic in full force on a project recently (lots of dialogs in this program). Not sure how many LabVIEW reboots it has saved me from. Reuse VIs made it even easier to do.
There are only two ways to tell somebody thanks: Kudos and Marked Solutions
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Bob,
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LarsUlrich wrote:
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What is your LabVIEW version?
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Hello tonitpp:
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Question about subvi front panel

I want to call a subvi in the main program and do like
this:
1. When the main program calls the subvi, the subvi shows its front
panel and executes.
2. After the subvi finishes, it can close the front panel.
Now, I meet a problem: I can popup the subvi node setup dialog to enable
"show front panel when called", which implements the first one, but I
can not close the front panel until originally closed(main
program stops). How can I close the subvi's front panel(after it
finishes running) even when the main program is still running?
Thanks in advances.
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Before you buy.

In article <[email protected]>,
"Remco Breen" wrote:
>
> [email protected] wrote in message <[email protected]>...
> >In article <[email protected]>,
> >"Kevin B. Kent" wrote:
> >> [email protected] wrote:
> >>
> >> > Now, I meet a problem: I can popup the subvi node setup dialog to
> >enable
> >> > "show front panel when called", which implements the first one,
but
> >I
> >> > can not close the front panel until originally closed(main
> >> > program stops). How can I close the subvi's front panel(after it
> >> > finishes running) even when the main program is still running?
> >
> >
> >
> >
> >> Select the "close front panel if originally closed" option.
> >> in addition to the "Show front panel when called"
> >>
> >> Kevin Kent
> >
> >
> >I have tried this, in this way, the subvi's front panel is closed
only
> >after the main program stops. In fact, what I want is to close the
> >subvi's front panel even the main program is still running.
> >
> >
> >zhljh
> >
> >
> >Sent via Deja.com http://www.deja.com/
> >Before you buy.
>
> Another option would be to open a VI reference (found under
"application
> control") and tie that to a property node and select the property
"front
> panel.open". Change it to a control and attach a boolean false to it
when
> you like to close.
>
> RB.
>
I think a more elegant way of closing the SUB VI is to start off the way
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Server" example. It demostrates this techniques better than I can
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Rick
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Hi devchander,
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Message Edited by tbd on 08-17-2006 11:45 PM
Message Edited by tbd on 08-17-2006 11:48 PM
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MouseTrap.vi ‏138 KB

My front panel doesn't show

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I have a vi (1) that calls a subvi (2) when I press a button. This subvi (2) calls the vi (1) again when I press another button. I have a event structure for this button (button of the subvi (2) ) where I set to false FP Open property for the vi (1) and then I call by reference this vi (1) and I do an invoke node (run) to show the front panel of it but it doesn't work. Why?
I post an image.
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Attachments:
blocks.JPG ‏41 KB

Hi ToNi
I attach you another 2 simple solutions. One with the FP.State property and the other using the close function of the vi reference.
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Calling vi front panel object update in a running sub-vi loop?

Hello All. I have a calling sub-vi with a "Start Test" button on the front panel. I passed a control reference for that Start button into a sub-vi that runs in a while loop. The while loop is monitoring that Start button and other things.
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Lets just whip up a little example then shall we?
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Go ahead and run the top vi. Press OK and watch the value of Value change (up to 20 times per second but that is faster than your eyeball).
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Front panel doesn't show

Hi,
I have a vi (1) that calls a subvi (2) when I press a button. This subvi (2) calls the vi (1) again when I press another button. I have a event structure for this button (button of the subvi (2) ) where I set to false FP Open property for the vi (1) and then I call by reference this vi (1) and I do an invoke node (run) to show the front panel of it but it doesn't work. Why?
I post a image.
Thanks,
ToNi
Attachments:
blocks.JPG ‏41 KB

Hello tonitpp:
Unfortunately, the "Run VI" method only executes the vi and it will not open the front panel.
If you want to open the front panel, use the "Open FP" method, which is also located on the same class.
I hope this helps.

Problem about asynchronous call: subVI front panel doesn't pop up when called.

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