Thank you for your very comprehensive response!
Dan
JB Parrett wrote:
> on 8/31/00 1:49 PM, Dan Samber at [EMAIL PROTECTED] wrote:
>
> > As part of my voyage away from the newbie kingdom, I have made my
> > first encounter with the land of databases.
> >
> > The Memopad tutorial slowly evolves until it is (by I think Memopad7)
> > editing the database "in-place". While I understand the benefits of such
> > a maneuver, it SEEMS to me that this arrangement would get increasingly
> > difficult for databases whose records consist of more than the one field
> > as demonstrated in Memopad.
>
> I find editing in place useful for Notes forms, where the potential amount
> of data might prove problematic for the dynamic heap on some
> devices/configurations (by default, edit fields use the dynamic heap to
> manage their contents during editing).
>
> However, if a form has several edit fields and they map to database fields
> within a record, you can only link one edit field with one DB field at a
> time. You use FldSetText() to create the link (the Field manager and the
> Data manager work together to resize the DB record as the user edits). The
> extra work comes when the user tabs or taps into another edit field.
>
> For these cases, before you can use FldSetText to link the new edit field,
> 1. compact the heap space used by the edit field so that your DB record is
> as small as possible (FldCompactText(pFld))
> 2. disassociate the edit field's text handle from the database
> (FldSetTextHandle(pFld, NULL)).
> And you must do this for all the ways the user can switch to another field
> (tap into field, tab from a keyboard, write Graffiti next- or previousField
> chars).
>
> Not difficult to do, and probably the right approach for some apps, but for
> most of mine, I just set all the fields' contents with copies of the data
> when the form receives a frmOpenEvent (note: you'd have to do this anyway),
> then when I'm ready to copy data back to the database, I check for edit
> fields that have changed and copy their data back to the record, resizing as
> necessary.
>
> Summary:
> Edit in place: the OS takes care of resizing the database record; you take
> care of making it happen at the appropriate times.
> Otherwise: you must resize the database record before copying back the
> edited data; the system handles editing and user navigation.
>
> JB
>
> ----------------------------------------------
> JB Parrett [EMAIL PROTECTED]
> Palm, Inc.
>
> We grow a lot faster than trees,
> so we miss a lot of stuff. - B. Andreas
>
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