topic Re: Using a Multicolumn Listbox To Retrieve Selection Items in LabVIEW

Using a Multicolumn Listbox To Retrieve Selection Items

hobby1 — Wed, 27 Aug 2014 20:12:43 GMT

Hello, I want to use a Multicolumn Listbox as a control. This control will popup to a user and the user can select as many items (rows) as they would like. When they are done with selecting which items (rows) they would like to select they hit the Done key to end the selection process. Programatically, I then would like to create an array for all of the items (rows) selected. I have two headers: Test Code and Test Name. I would like to programatically create an array with the Test Codes and the Corresponding Test Names.

I think I can do this with property nodes but I am a bit new to using Listboxes. What is the best way to do this?

Thanks!

Re: Using a Multicolumn Listbox To Retrieve Selection Items

aputman — Wed, 27 Aug 2014 20:28:04 GMT

A multicolumn listbox allows you to select 0 or more items by right-clicking on the control...Selection Mode....0 or more (or 1 or more depending on your requirements). You'll want to setup an event to fire when the value of the control changes. The new value will be an array of indexes that were selected by the user.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

hobby1 — Wed, 27 Aug 2014 20:59:09 GMT

Thanks Aputman...If I have two columns of data for each row, is there a way to return that information based on only the selected items?

For example - My two column headers are:

Test Code and Test Name

Is there a way to return the Test Code and Test Names based on the selected rows?

My list box looks like the following:

Re: Using a Multicolumn Listbox To Retrieve Selection Items

manel549 — Wed, 27 Aug 2014 21:15:47 GMT

Hello hobby1,

I think you could use the invoke node of the multicolumn listbox which is "Point to Row Column". This property gives you the location of the selected row. See the example below. Any doubt just post it.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

aputman — Wed, 27 Aug 2014 21:31:47 GMT

Use a property node with the Item Names selected. This will return an array of your data. All you have to do is index that array with the new value array returned by the event to give you another array with the selected Test Code and Test Name columns. Try it out and if you have trouble, i can show you. Best way to learn is to try.yourself.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

aputman — Wed, 27 Aug 2014 21:42:04 GMT

@manel549 wrote:

Hello hobby1,

I think you could use the invoke node of the multicolumn listbox which is "Point to Row Column". This property gives you the location of the selected row. See the example below. Any doubt just post it.

Manel,

I don't think this is a good idea. That method only seems useful on a table where you can select a single cell. In a multi-column listbox, you are only concerned about the row(s) selected. That method only returns one point for one row/column combination. And honestly, I may be wrong because i don't use that method.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

Miraz_Automation — Thu, 28 Aug 2014 05:24:43 GMT

Hi,

Please check attached VI it may help you!!!

Re: Using a Multicolumn Listbox To Retrieve Selection Items

DavidStevenson — Tue, 02 Sep 2014 13:03:27 GMT

( to hijack this thread) Thanks that is just what I was looking for.

Now if I could select multiple items without the control / shift keys it would be perfect.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

LV_user1 — Tue, 02 Sep 2014 13:26:45 GMT

Hi David

I am not sure without pressing control /shift key how will you point how many items you want to select?

Re: Using a Multicolumn Listbox To Retrieve Selection Items

DavidStevenson — Tue, 02 Sep 2014 13:29:05 GMT

If you hold down the cntl key you can click on an item to select it, or if already selected deselect it, and add and remove selections till you have the list you want. Then you click done.

What I would like is this usage without needing to hold down the cntl key.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

aputman — Tue, 02 Sep 2014 13:37:48 GMT

that can be accomplished. Try using a mouse down filter event on the listbox. Use the Point to Row Column method to get the row. Check to see if the value is already in the listbox array. if so remove it. If not, add it. Update the display of the listbox. Then discard the mouse down event.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

crossrulz — Tue, 02 Sep 2014 13:38:52 GMT

DavidStevenson wrote:What I would like is this usage without needing to hold down the cntl key.

But that goes against every single UI I have ever seen. That would just confuse users.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

DavidStevenson — Tue, 02 Sep 2014 13:45:57 GMT

aputman: Thanks, I will have a play with that. ( the lazy part of me says any example code? 8-) )

crossrulz: It depends on whether the machine has a keyboard.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

aputman — Tue, 02 Sep 2014 14:09:25 GMT

OOOOOKKKKKKK.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

apok — Tue, 02 Sep 2014 16:12:19 GMT

just mouse down on any row, shift reg saves values...

Re: Using a Multicolumn Listbox To Retrieve Selection Items

DavidStevenson — Tue, 02 Sep 2014 21:13:45 GMT

My thanks to both of you.

Re: Using a Multicolumn Listbox To Retrieve Selection Items

danny_t — Tue, 10 Nov 2015 10:23:50 GMT

I know this an old thread, but could somebody point out my obvious mistake.

I was looking at the example posted by apok and have on major problem.

When ever I put a MCL onto a front panel and look at the "value" property node I only see it giving my a long 32 int not an array. I asumed that to get an array out of value I need to set someother property, but after an hour playing I cannot find which one. Help please

Re: Using a Multicolumn Listbox To Retrieve Selection Items

tst — Tue, 10 Nov 2015 11:29:26 GMT

@danny_t wrote:

When ever I put a MCL onto a front panel and look at the "value" property node I only see it giving my a long 32 int not an array.

You need to right click>>Selection Mode>>Data type>>Array

Re: Using a Multicolumn Listbox To Retrieve Selection Items

danny_t — Tue, 10 Nov 2015 11:40:35 GMT

Thank you for the quick reply.

Really do not know how I missed that one .