Re: Pushing the limits of a list view
- Posted by Don <eunexus at yahoo.com> Jun 02, 2004
- 459 views
> > > I've got a program that dynamically builds a list view (columns and data > > > rows). In one situation I added 700+ columns to the list view. The data > > > displays fine but the column headings are not drawn after columns 396. > > > As a matter of fact, column 396 is only half drawn! Is this a known > > > limitation? If not, I guess I'll have to dig and figure out why.... > > > > I don't have your answer, but I'm very curious as to why you > > need so many columns! :D > > > Well, I wasn't going to go into the details but...a user of my FROG > database browser reported the problem. With FROG the user can open any > database file and browse the records in the file. One file in particular > has 796 columns! So a "select * from myfile" returns every column in > the file. I adivsed the user to limit the number of columns returned but > it's much easier to type a "select *" than "select fld1, fld2, fld3, etc..." > > It's pretty unusual to have files with that many columns but it does > happen! > > Jonas Heyas Jonas =) I dont have all the answers as regards to this particlar question, but I do know some of it. Behind the scenes, the ListView API (as regards to the actual drawing) is limited to 16 bits of resolution. You can (I think) have as many columns as you like, but it will not be able to draw anything past 16 bits (32768 pixels) in width. The only solution(s) that I am aware of is either A) use a custom control that does not have this limit or B) use smaller columns to pack in more visible area I would opt for A personally... if you can find a good one. Don Phillips National Insturments mailto: eunexus at yahoo.com