Determine which record is displayed at top of continuous form when user uses the scroll bar to scroll down

Dale Fye
Dale Fye used Ask the Experts™
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I'm trying to determine the PK of the record displayed at the top of a continuous subform.

I have a subform which contains times from 07:30 - 17:00 in 15 minute intervals.  Unfortunately, I can only display about 20 of these records at one time, so I have the vertical scrollbar enabled.  If the user scrolls down, using the vertical scroll bar, I want to be able to determine what time interval is locate at the top of the visible section of the subform.

I know that if the user scrolls down and then selects the top most record, I can use the SelTop property of the form, but this value does not change unless the user actually selects the record at the top of the form.  Any ideas:
1.  What event to use to check whether the user has scrolled down
2.  how to determine the time associated with the record displayed at the top of the form.

Thanks,

Dale
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John TsioumprisSoftware & Systems Engineer

Commented:
Probably if you study the code from Leban's ContinuousFormsCurrentRow you could tackle this...it has being quite some years i fiddled it with it but if my memory serves e right you will able to "decode" the Continuous form Vertical location so you could find out the upper- lower bounds of it...
Jim Dettman (EE MVE)President / Owner
Most Valuable Expert 2017
Most Valuable Expert 2012

Commented:
Someone also had the ability to read the position of the thumb on the scroll bar, but memory fails me at the moment :(

Also I don't think it would have been accurate enough to get a specific record.

Jim.
John TsioumprisSoftware & Systems Engineer

Commented:
The code of Lebans i think it does that.....if there is another implementation of CF thumb it would be extremely interesting Jim to find and share it....from my search something like this has being done for ActiveX ListView.
Dale FyeOwner, Dev-Soln LLC
Most Valuable Expert 2014
Top Expert 2010

Author

Commented:
Actually, Steve's code does not work correctly, at least not when converted to A2007, and in order for it to work, you have to mouse over the records, which I don't want to have to do.  Additionally, the data displayed at the top of the form, when you mouse over the Code field of the first record displays the data for the 2nd record.  Then, as you scroll down, it displays the data corresponding to the record above it, not the one that the mouse is over.  Furthermore, if you actually move the scrollbar down to display records 5-9, and mouse over record 5, it will display the data from record 1 (the second record displayed when the scrollbar is all the way up).

I think what I'm really looking for is the number (X) which displays in the control tip when you click and drag on the scroll bar (X of Y).  I'm not aware of a scrollbar event, though so I don't know how to get that value.
Distinguished Expert 2017

Commented:
Hi Dale,
I've never actually tried to use the sample code but maybe you can create your own scrolling.  I don't like hardcoding things but since you know you can only show 20 rows, perhaps you can use that to your advantage by selecting ONLY 20 rows at a time.  That way you always know what row is at the top.  You can create 6 down and  up buttons - Top, Bottom, down 1, down 5, up 1, up 5
Jim Dettman (EE MVE)President / Owner
Most Valuable Expert 2017
Most Valuable Expert 2012

Commented:
That's an excellent thought Pat.

Jim.
Dale FyeOwner, Dev-Soln LLC
Most Valuable Expert 2014
Top Expert 2010

Author

Commented:
Pat,  That was my fall-back position, if I couldn't find someone who knew how to do this.  Unfortunately, that doesn't handle the situation where the user actually selects a record and then uses the up and down arrows to move up and down through the recordset.  I'll have to do some more thinking on this.

Seems strange that there is not method or property of the form that would provide that info.  Sounds like a UserVoice request.
Jim Dettman (EE MVE)President / Owner
Most Valuable Expert 2017
Most Valuable Expert 2012

Commented:
<<Pat,  That was my fall-back position, if I couldn't find someone who knew how to do this.  Unfortunately, that doesn't handle the situation where the user actually selects a record and then uses the up and down arrows to move up and down through the recordset.>>

 Capture the up/dwn and either eat them up, or use that to control your custom scrolling.  Ditto for page up/down.

Jim.
President / Owner
Most Valuable Expert 2017
Most Valuable Expert 2012
Commented:
Dale,

  Not sure this will get you where you need to go...it was Leban's code that I was thinking of:

http://www.lebans.com/setgetsb.htm

Jim.
Dale FyeOwner, Dev-Soln LLC
Most Valuable Expert 2014
Top Expert 2010

Author

Commented:
Thanks, Jim, I'll take a look.
Dale FyeOwner, Dev-Soln LLC
Most Valuable Expert 2014
Top Expert 2010

Author

Commented:
Jim, that was precisely the solution I was looking for.

I'm disappointed that there is no scroll bar event that we could use to trigger this info, but I guess I'll do as Stephen did and use timer event.

Thatnks John and Pat for your suggestions.
Distinguished Expert 2017

Commented:
You're welcome.  Please post any improvements to the Leban's code you come up with.
Jim Dettman (EE MVE)President / Owner
Most Valuable Expert 2017
Most Valuable Expert 2012

Commented:
<<Jim, that was precisely the solution I was looking for.>>

 Glad to hear it pretty much got you where you need to be.

<<I'm disappointed that there is no scroll bar event that we could use to trigger this info,>>

  There's more than a few things we'd all love to see in Access.   It's too bad that Microsoft focused on the web for so long.   I understand why, but they really could have made Access a lot better for the desktop had they not.

Jim.

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