CListCtrl with 1000's of entries is too slow

I'm using a CListBox to display entries from a large database. My problem is that as the number of entries exceeds a couple of thousand, the time taken to re-draw the ListBox becomes prohibitive. Is there a way of only writing to the Listbox enough entries to fill the screen and then loading new ones from the database as and when the listbox is scrolled. This effect can be seen in the explorer when a directory contains many files. I know that one approach is to use some kind of "virtual listbox" but examples I have seen are very old.
l.hudson02Asked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

chensuCommented:
Before adding entries, you should call CWnd::SetRedraw (CListBox is derived from CWnd).

void CWnd::SetRedraw( BOOL bRedraw = TRUE );
 
Parameters
bRedraw   Specifies the state of the redraw flag. If this parameter is TRUE, the redraw flag is set; if FALSE, the flag is cleared.
Remarks
An application calls SetRedraw to allow changes to be redrawn or to prevent changes from being redrawn.
This member function sets or clears the redraw flag. While the redraw flag is cleared, the contents will not be updated after each change and will not be repainted until the redraw flag is set. For example, an application that needs to add several items to a list box can clear the redraw flag, add the items, and then set the redraw flag. Finally, the application can call the Invalidate or InvalidateRect member function to cause the list box to be repainted.


0

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
System Programming

From novice to tech pro — start learning today.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.