Read the Frame names of a case structure

[LAVA 1.0 Content]

Why this piece of code does not work everytime? Anu suggestuons availabe?

[Tomi Maila]

QUOTE(guruthilak@yahoo.com @ Feb 11 2008, 12:18 PM)

Why this piece of code does not work everytime? Anu suggestuons availabe?

It would be helpful if you described how the code doesn't work.

p.s. Don't forget to close the block diagram reference.

[LAVA 1.0 Content]

QUOTE(Tomi Maila @ Feb 11 2008, 05:47 AM)

It would be helpful if you described how the code doesn't work.

p.s. Don't forget to close the block diagram reference.

OK here you go...

this piece works very well when i just a have a vi with a case structure with only 2 frame names (True and false) . When i put it in to the application which i have developed (which is having more than 100 states in a state machine) it does not work. It throws the error as "Invalid object reference" or someything similar to that

[Aitor Solar]

QUOTE(guruthilak@yahoo.com @ Feb 11 2008, 12:32 PM)

this piece works very well when i just a have a vi with a case structure with only 2 frame names (True and false) . When i put it in to the application which i have developed (which is having more than 100 states in a state machine) it does not work. It throws the error as "Invalid object reference" or someything similar to that

I haven't found any problem, but didn't try so many cases.

The error is thrown in the "Open VI Object Reference" node, isn't it? Is it possible the frames are located inside another structure, and so the fuction can't find them?

Saludos,

Aitor

[Norm Kirchner]

Have you thought that you possibly have 2 structures named the same thing?

Have you tried re-naming it to something simple and trying again?

[Aristos Queue]

QUOTE(guruthilak@yahoo.com @ Feb 11 2008, 05:32 AM)

When i put it in to the application which i have developed

Are you actually building this into an EXE or DLL? If so, the problem would be that VIs don't have block diagrams in a built application. The runtime engine doesn't support any of the functions for inspecting the diagram. You would definitely get an "invalid object reference" in that case.

[LAVA 1.0 Content]

QUOTE(Aristos Queue @ Feb 11 2008, 05:25 PM)

Are you actually building this into an EXE or DLL? If so, the problem would be that VIs don't have block diagrams in a built application. The runtime engine doesn't support any of the functions for inspecting the diagram. You would definitely get an "invalid object reference" in that case.

I AM not using this in in a exe or dll. The only thing is that this case struture is within a "while loop". and only in this application it throwing the errror.. When i try it with a new simplae vi it works fine.

[Ton Plomp]

QUOTE(guruthilak@yahoo.com @ Feb 12 2008, 07:24 AM)

I AM not using this in in a exe or dll. The only thing is that this case struture is within a "while loop". and only in this application it throwing the errror.. When i try it with a new simplae vi it works fine.

OK that makes sense,

you should navigate your way to the case structure, so first open a reference to the 'while loop' and then open a reference to the structure within.

Ton

[Norm Kirchner]

Actually you should probably just use the TraverseforRef vi and then simply do a named filter.

It will provide much more robust results as you don't have to care about who is the immidiate parent of the case structure.

[wishfulthings]

This is exactly what I want to do but I'm using 8.6 and can't seem to get access to the Block Diagram property node. Is there a similar method I can use for 8.6.

This is my first post and I only have a few months Labview experience so hopefully this isn't a stupid question

[crelf]

QUOTE (wishfulthings @ Feb 12 2009, 06:18 AM)

This is exactly what I want to do but I'm using 8.6 and can't seem to get access to the Block Diagram property node. Is there a similar method I can use for 8.6. This is my first post and I only have a few months Labview experience so hopefully this isn't a stupid question

That's not a stupid question at all (I actually did the same thing yesterday), but you may not like the answer: there is a way to get the block diagram property node, but it's a private method - http://forums.lavag.org/VI-Scripting-Readme-First-t1207.html' target="_blank">read here for more information on how to get access to private methods.

[Grampa_of_Oliva_n_Eden]

QUOTE (wishfulthings @ Feb 12 2009, 06:18 AM)

This is exactly what I want to do but I'm using 8.6 and can't seem to get access to the Block Diagram property node. Is there a similar method I can use for 8.6.

This is my first post and I only have a few months Labview experience so hopefully this isn't a stupid question

Could you please explain what you are trying to accomplish?

A first LV project should not require advanced technique like Scripting. Maybe we can offer a simpler approach.

Ben

[wishfulthings]

QUOTE (crelf @ Feb 17 2009, 04:07 PM)

That's not a stupid question at all (I actually did the same thing yesterday), but you may not like the answer: there is a way to get the block diagram property node, but it's a private method - http://forums.lavag.org/VI-Scripting-Readme-First-t1207.html' target="_blank">read here for more information on how to get access to private methods.

Thanks for the info. I've now got it working perfectly

[crelf]

QUOTE (wishfulthings @ Feb 24 2009, 05:57 AM)

Thanks for the info. I've now got it working perfectly

No worries. Care to upload what you did so we can take a loo?

[wishfulthings]

[wishfulthings]

QUOTE (crelf @ Feb 24 2009, 04:00 PM)

No worries. Care to upload what you did so we can take a loo?

I have attached a number of VIs and will attempt to explain their operation. Download File:post-14706-1235987484.vi

Download File:post-14706-1235988461.vi

Download File:post-14706-1235988471.vi

I have been tasked with trying to make a sequencer using a state machine with perhaps 100s of cases. I decided it would be nice to split the cases into groupings which were more logical, ie all cases relating to GPIB instruments together in a seperate VI, cases for switching in another vi etc... In doing this my difficulty was to then know in which vi a case resided. This was necessary as to open each vi sequentially and then look for a case was causing unacceptable delays when running the application. So I needed to create a look up so I would know exactly where to find each case. This was how I did it but there may be a much cleaner way.

Firstly the "Read Case Names.vi" reads all the cases in the vis located in a test sequences subdirectory up from my working directory and writes them to a cases.txt file.

Then the "Write Case Locations.vi" writes the cases and their locations to two seperate arrays.

These have been incorporated into a "Create Control.vi" which then creates a control for all the cases which enables me to use the cases as strict typedef enum which I can use to then select my next state(s) in the state machine.