stepping through table is very slow

[GabbyG]

LV 7.0 on Win 2K
I use a table to display records of information. The table is filled once at entry to a user interface subprogram and the user has the possiblity to select certain records by clicking or stepping through with the cursor buttons.
I have also written subprograms to sort the table by the various columns. The active row is used to provide more information e.g. displaying it in an image.

Usually you would click on a line with the mouse, but somtimes it is more convenient to step through subsequent lines with the cursor buttons.

As it turned out the latter is sometimes very slow.

I tried to trace that behaviour in my program, but it seems that the problem is within labview. I reduced the vi to a simple loop
where nothing is done with the table except to display the value. If you click on a line the value will follow instantaniously. If you click on a line at the top of the table and then step down with the cursor buttons the value will also follow very quickly. But when you do the same while beeing at the bottom this will take several seconds.

I read several entries in the forum that describe similar problems when updating the table. Please note that this is a very static table here. The only thing that is happening, is a user interacting with it with the keyboard.
The answers I saw so far, suggesting to keep the table small, or switching to other indicators etc. seem to overlook the reason why to use the table; that is tp have a compact display of a lot of ordered information. If the reason is really within LV runtime. Than NI has a nice task to improve LV next time 😞

Gabi

[altenbach]

Unfortunately, I can confirm that LabVIEW 7.1 shows the same slow behavior. Actually pressing "down arrow" on my rig is so slow, it seems to lock up the PC. (W2k)

Interestingly, if you capture the "up" and "down" arrows with a filter event, there is no slowdown! Maybe you can used the attached rough draft (LabVIEW 7.0) to improve the UI experience to the user until NI fixes the issue.

Enjoy!