Front panel property: Selection list

[wildcatherder]

I cannot find the examples in this thread.

I think the "get a reference to the front panel" is the sticking point.

How is this done in Labview 2009 or 2010?  "Selection List" does not appear on any menu I can find.

[tst]

My first post has a link to another post which has an LLB which demonstrates the use.

This is the simplest example:

[wildcatherder]

I appreciate that TST is responding.  I did find the link to the example (disguised as the word "this").  It is wonderously complex.  I know that you think this makes it obvious how to do what I am asking but it just doesn't.  In your simpler example, just posted, I have no idea what the second icon (from the left) represents or how to get to it.

Please, if you cannot spare the time for a simple procedure (open this, right-click here) telling how to get to the Front Panel Properties - Selection List, let the post sit until someone is willing to do this.

[RavensFan]

Please be careful with the wording in your messages.  You have been given a lot of help, and need some more, but the way you asked sounds very negative and unappreciative.

The second icon is a property node.  Right click on the vi reference connector coming out of the open function.  Go to Create >>  Property for VI Class >>  Front panel.

Now that will be dropped and you just need to connect it.

Now right click on the Panel reference.  Create >> Property for Panel Class >>  Selection list.

Drop it and connect that.

[tst]

The second node is called Open VI Reference and it can be found in the Application Control palette.

Frankly, the Selection List[] property is something that would usually be used by someone advanced enough to know how to access these things, and I didn't even realize until now that you don't know how to do that. If you don't, how would you expect to be able to use the references you get?

What do you actually want to do?

[wildcatherder]

Thank you for your descriptive reply.  I do not know what is meant by "vi reference connector coming out of the open function". 

I understand that this is a complex subject, which is why I am asking for help.  The Selection List was suggested to me (in a posting on Community Nugget) as a way of identifying object-layer associations on the front panel:

"There is one round-about way, though - the Selection List[] property returns the reference sorted in two levels - the first level is based on selections you made (i.e. if you select objects and then use Shift to select another group) and the second level (for reasons I can't fathom) is by reverse Z order. So, if you select all the objects on the FP (Ctrl+A) and use that property, you'll get the order."

From the context, this appears to be something that can be done in Edit Mode (since one is selecting objects).  It is unclear how these programmatic examples enable me to do what was suggested, but I am trying to learn.  Is there some way to access the Select List in Edit Mode?

[RavensFan]

"When in doubt, right click" is useful to learn.

The open function has a bunch of connectors, or terminals that you wire the inputs and outputs to.  If you hover over one of those terminals, a spool of wire shows up.  When that happens, right click.

Using right click and Create (whether control, indicator, constant, or property or invoke node) is a good way to create something of the correct datatype or class without doing a lot of work creating it from scratch or searching for it.

If you don't know what property nodes are, then I would recommend looking at the online LabVIEW tutorials
LabVIEW Introduction Course - Three Hours
LabVIEW Introduction Course - Six Hours

I'm not sure of what you are ultimately trying to do, or whether playing with property nodes is the best way to get you there.

[wildcatherder]

With TST's response about the unidentified icon, telling me that it is the Open VI Reference VI, I was able to find the VI Reference output connector and create a Panel Property Node and from there a Selection List Node.  I created a copy of the simple example he provided and embedded it in my VI.  I attached an indicator to the Selection List output.

The attached JPG shows the indicator as it appears on the front panel.  Unfortunately, I do know know what it is supposed to be indicating.  Are there supposed to be icons in the little box, numbers, ?

I am familiar with the basics of property nodes.  I use them all the time.

[tst]

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@wildcatherder wrote:

The Selection List was suggested to me (in a posting on Community Nugget) as a way of identifying object-layer associations on the front panel:

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That sounds familiar, possibly because I was the one who wrote that text earlier today 😉 . I wrote it under the assumption that the person reading it has certain basic knowledge, such as how to open a reference to another VI and use property nodes. I would agree with RF that if you don't know how to do those, some tutorials or looking through the help and examples would be beneficial.

Personally, I never had an actual need to find out the Z order. Why do you need this?

[Darin.K]

Now the can of worms is opening.  What you have is an array of GObject references.  Simply put, these are references to generic objects, and as such they have limited properties and methods available to them (only those shared by ALL objects).

You can pass that array into a For Loop and for each reference read the Class Name property, you'll see things like Array, Digital, String, etc. which can start to narrow down the search.

To start doing useful work, you have to cast a given reference to the correct type using the 'To More Specific Class' function.  If you try a cast that fails, you get an error out (useful information).  Beware, the reference out becomes bad as well.

I could go on and on, but we need a sense of what you are trying to do, and how badly you want to do it.