I would like to do something smarter than just have the entire screen
redrawn every time an udpate needs to happen.  My screen is a table and each
row is an entry into a pdb which has potentially thousands and thousands of
records.  That means to access DmQueryRecord might take over a second for
each row.  I'd like to make sure that I'm only re-accessing my table data if
I need to.  I was thinking about a cache but it is possible that the rows
might change some of their values between updates.  So if I cache, I need to
make any updates to the DB also update the cache.  I jsut can't stand to
have the entire screen slowly redrawn (sometimes twice) every time I update
the state of 1 row!  This is a very generic problem that most anybody who
has a frame consisting of a table should understand.  I guess the crux of
the problem is that I'm not sure how to tell which rows are still the same
as they were at the last full screen draw.  If I store the PDB UID as table
data, I *still* don't know that that the row's UID (i.e. I can't check if it
is the same as the last time I drew) until I do a DmQuery by position (the
way I have it written now) which entails a slow DB access.  How can I setup
a cache-verify which does not involve at least 1 DB access?  How have you
all solved these issues?



-- 
For information on using the Palm Developer Forums, or to unsubscribe, please see 
http://www.palmos.com/dev/support/forums/

Reply via email to