Michael Aivaliotis

If you look at the advanced pallete in LV7 you will see the input device control subpallete. There is a VI that returns the scroll position. I tried running this but could not get it to work. If we could get this to run I think we would be on our way to solve the problem of trapping the scroll button.

Here is one way to do it...

Yes, well you don't really have to do it the way they show. I mean you can also just respond to that event. You will have to get the references to those vi's that want to send an event then you can respond to a panel close or anything else. The way the existing event system works in LabVIEW requires that there be an event case for the specific event you are responding to. You cannot dynamically register NEW events only re-assign existing registrations to other VI's or controls. Hopefully this may be added in future releases.

Just be carefull when using Match Pattern. Sometime you forget about special characters that are used in the regular expression input. See example: As you see we are looking for \b and can't find it since it thinks we want the backspace code. Of course this can be ignored by using \\b but you should be aware of this especially if your regular expression is programmatically generated.

This is a confirmed bug from NI support that was just recently reported. I'm surprised that it hasn't popped-up earlier than this. Create a multi-column listbox with about 5 columns and 1000 rows of data. Make sure you have 1 or more items selection capability enabled. Now using the selection tool (finger) click on the first row then scroll to the bottom of the list and shift-click the last row. This effectivly selects - highlights ALL rows. After doing this, LV hangs. At first I thought that LV crashed but eventually it comes back and displays the selection. It seems to take longer to come back with the more rows of data you select. Regardless, this is definitly an issue since no-one will wait 5 minutes or more for a user interface to respond. In all essence LV is crashed.

I assume you have seen the NI example called: Dynamically Monitor VI's.vi. This will do what you ask. It is a combination of firing events and monitoring panel states. The entire process is very fast and efficient. You can also investigate ActiveX events that implement VI callbacks. Look at this post for more details.: http://forums.lavausergroup.org/index.php?showtopic=61

:question: Here is an image of an example that will pass an event to another VI when a timeout has occured. remember to right-click on the event structure and select Show Dynamic Event Terminals Can anyone suggest a better approach to passing a timeout event to another VI? Please post any suggestions.

Yes, this can be used on any html page that you want to get off the web. Once the data is received you can just parse out the important content. I made a VI that gets the nymber of registered LAVA forum users. I attached an image that shows how to do this. As you see, once the html page is retrieved, the rest of the process is just plain text string manipulation.

Listbox symbols can be changed using the Item Symbols property node. You need to feed-in an array of numbers which represent the position of the symbol as it appears on the front panel selector. If you look at the attached image, you will see that the Item Symbol selector on the front panel is high-lighting the X symbol. This symbol is position 2 in the selector if we count the first position as zero. If you go to the diagram you can see that we just build up an array of indexes that select the symbol we want to use. A much easier way to do this would be to use the Listbox Symbol Ring Constant located in the numeric constants pallette. This way we can use intuitive icons for selections. Don't worry, I didn't know this was there either until 2 years of using LabVIEW. This is not clearly documented. Another hidden feature is the ability to create a disabled line effect by entering -1 as an item symbol. Don't try to find the line symbol in the constant. It isn't there. It's only visible on the front panel selector. I guess this is a bug or an ommision. One final thing to watch out for. Symbols will only show-up for item lines that have text in them! Enjoy.

I use Photoshop. Since I started using it a year ago, I find it to be the best program out there. This is what I use for the LAVA site. I used it to create the text in the logo and headers and the special button graphics on this forum. It really can't be beat. My most favorite feature is the drop shadowing effects. Whenever I use it I find it adds depth and realism t text and graphics. If you don't want to spend too much money and want a simple interface, there is Paintshop Pro. It is not so loaded down with complex features and capabilities but it does the job well.

I think this is a good demonstration of using graphic images to replace common elements of a control. This VI sparked an idea that we could add to the wish list. See how you have tiled several images to create a background? I think it would be great to have the ability to specify an image in the VI properties and let LV tile then automatically. This would be similer to the HTML tag in web pages to tile a background.

Actually, Jack you are right, there is a leap year issue. I'm not sure why it is working for you because it is NOT working for me. I think you should NOT just subtract the 66 years in seconds. You should be subtracting the number of seconds until jan 1 1970 from 1904.

It turns out that NI doesn't perform this service anymore. For legal reasons they have stopped doing this.

Don, Could you re-post the attachment called "NI week interface slides lv7.zip"? While upgrading the forums I discovered that this file was not uploaded properly and was in fact blank!

Have you considered using the Remote Panels feature in LabVIEW? I've used this extensivly and found it to be an easy and safe way to handle remote monitoring and control. In addition, the clients can be running web browsers so you don't need to build a custom application to handle the VIserver communication.

I'm not sure if you are referring to embeded panels. I'm assuming you need a standard pop-up VI. The easiest way to create a pop-up VI panel is to set the VI to open the panel when called and close the panel if originaly closed. See the attached image: In order to bring up this property window, you must right-click on the icon in the top-right corner of the front panel of the VI you want to make pop-up.

I think you're in trouble there. There are several people who have attempted to crack the passwords in VI's but have not succeeded. In any case, you may still have an option. National Instruments may be able to unlock the VI's for you. You have to prove that you are the owner of the code. If you are truly the owner of the code and you have your name or company name printed somewhere inside the diagram or fornt panel, then Ni will help you. This information was given to me several years ago. I don't know if NI still performs this service.

A similer question was posted on Info-Labview. Here was my response:

Well, I zipped the messages since Oct. 17-2003 until today. If you have Outlook (sorry) you can view them... Here they are: Download File:post-11-1073099085.zip

Well, it looks like it's back again.

Well, I don't think there are any exposed properties for this. There may always be some hidden ones. :wink: In any case, there may be a workaround, it depends on what you're after. If you use the "classic" cluster then you can make it transparent. This will make the frame go away and then you can put another object behind the cluster so the outline of it is shown behind it. Then you can change the colour of this object (color box?)via a property node. There is another option to embed this object as an element within the cluster. However this introduces an unnecessary data object which you may not want.

Yes, well I guess the term "online reference" is a generic name for any help resource available. More specifically what you want is Application Note 168. It is available online at NI.com here: http://zone.ni.com/devzone/conceptd.nsf/we...D3?opendocument

I think I found your problem. You should never split the event registration refnum. If you delete the connection circled in the image below you will see that everything works fine. You are not using any of the dynamic events in that event structure anyway so why do you have it wired? I think this was mentioned at NIweek this year in the presentation on event structures. Even though the top event structure does not have any event cases to handle the events, it still looks at the events and if it catches it first will discard the event.