Main/subVI control confusion

hello one and all,
i am a little confused on the best way to approach this. i have a main and sub VI. the main VI is the main VI and the sub VI has a complex settling routine and after all the little parameters have settled out, it quits its while loop and returns control back to the main which collects, averages, and manipulates the settled data.
ok, so i want the stop button on the main VI to stop the sub VI while loop in mid stream if need be; to gracefully exit the program. so i experimented with Notifiers, which worked well with the latter. but then i need to pass input parameters changes from the main into the sub and then when the sub is finished settling, pass output parameter changes from the sub back into the main. i tried Notifiers on that and it looks ok with the input parameters but gets pretty damn messy with the output parameters.
so what is the best way to approach and achieve input and output parameter changes while gracefully aborting nicely? thank you in advance and have a great day. lucas p.s. i am using labview 2010 x64 bit under win7.

Take a look at the 'message handler' design pattern.
I'd use queues instead of notifiers, as passing a bunch of parameters would override each other when using notifiers.
Then use a 'message'-type-def-cluster. First part is the message such as SetParamA (use an enum or string), the second part is any data you want to send along such as parameter values (use string or variant + FlattenToString/UnflattenFromString or the variant functions). I did demonstrate this using events here.
You will need to code your message handler ('SubVi') to check from time-to-time if a new message is available. This is best modelled as a state-machine, where you either have an 'idle' state in which you wait for the next message or you check for new messages in each iteration and perform 'normal' states when the Dequeue gives you a timeout, otherwise first handle the message.
Felix
www.aescusoft.de
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"Art Lazaar" <[email protected]> wrote in
message news:[email protected]...
> Tralfaz,
>
> Thanks for your response. I must be missing something
very simple here, but I
> can't make this work no matter what I do. Let me see if
I understand some of it:
>
> On my main movie I put the fwd_btn and rew_butn
codes...do I put these on the
> actual buttons, or in an actions time line? When I put
them on the buttons, I
> get an error report saying they need to be in an 'on'
event handler. I thought
> that's what 'onRelease' was.
>
> On my loaded movie, I place the 'one.swf' code. I'm not
sure what you mean by
> placing the code inside a loop, I don't seem to be able
to find a reference to
> using 'loop' anywhere. When I use an 'onEnterFrame', I
presume I do that with
> onEventClip(enterFrame). When I do that, if I run the
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>
> Boy, am I confused ;)
>
> I am really baffled by this seemingly simple little
task. Your help is
> gratefully appreciated.
>
> Art
>
>
>
Hi Art,
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2) Attached code for movieclips and buttons
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Attached Code method to attach an onEnterFrame event to a
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the root timeline level)
onClipEvent(enterFrame)
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Those two types of code are not interchangeable. One type
must be entered into a frame and the other style must be attached
to a
movieclip or you will get errors.
Then there is the DOT syntax way to write frame code that is
equivalent to attaching code..
myMovieClip.onRelease = function()
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myMovieClip.onPress = function()
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tralfaz

Main/subVI control confusion

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