Conference abbott::visual_basic

2527.0. "Controls lost off SSTabs" by NUBOAT::HEBERT (Captain Bligh) Mon Mar 31 1997 10:49

I'm using VB4 Pro (16-bit) to develop an app that uses three tabs (the
SSTab control). I only have controls placed on Tab 1 so far. Yesterday I
found that clicking on tabs 2 and 3, then back to 1, caused four of the
controls on tab 1 to get "lost."

In the course of investigating this I found that when you click on tab 2
(say), the Left property of the controls on tab 1 all get set to about
-64000, which moves them well off screen. Then, when you click on tab 1
again, VB restores the Left property of all existing Tab 1 controls to
their respective values -- in other words, the horizontal position that
you set when you dragged each control into the position you wanted.

In the case of my "lost" controls, the Left property does not get
restored when I return to Tab 1. The Left properties range around -64000,
but the actual numbers are reflective if some arithmetic involving -64000
and the original Left property value. These controls are still in the Object
Browser, but now do not show up anywhere that's visible. I tried manually
setting the Left property to something onscreen, and that doesn't help.

Have any of you seen this? 

is it possible that there is a finite limit to the number of controls you
can place on a Tab? I think I placed maybe 20 controls on Tab 1 (I'm not
presently sitting at the system where I'm working on that app.)

Art

    I've seen this problem in the 32-bit version of VB4.0a with the added
    twist that the 'lost' controls appear on another one of the tabs. The
    only way I could find to fix this was to delete the shadow controls and
    recreate them. A right pain.
    
    Cheers,
    Brian

Thanks for the sanity check, Brian. At least now I know it's not
necessarily something I did.

WRT the controls showing up on other tabs -- yes, I see that happening,
too. *Sometimes!*

You know, I started out in this business in hardware (a *long* time ago).
I became accustomed to intermittent hardware problems. Intermittent
software is somewhat of an oddity.

I'll keep poking at this. Maybe a pattern will emerge.

Thanks,

Art

Did a little more looking last night. I started a new project with one
form, on that form was a basic 3-tab object, on tab 0 was just one
control, a text box. The problem described in .0 manifested itself. So,
this is not a problem with the number of controls on a tab control.

Art

Well, it turns out this is indeed bug number Q145567, which was
supposedly corrected in VB 4.0A. I guess I don't have that update on my
CD.

In fact, there is quite a list of bugs surrounding the SSTab control.

See:

www.microsoft.com/kb/articles/q140/6/12.htm

Art

Microsoft called me about my report. They said that VB4.0A fixed this
problem and some others, and they'd send me a new CD, sorry about that.

I'm happy.

Art