A word to the wise about the PBO of a docked tree

Question

I was just having an interesting discussion with Rich H and Max B over in ABAP Objects about "re-entrant" docked trees.  ("Re-entrant" in this case means you may have to rebuild the same tree control from a different root during the same execution of the program - this is not exactly what "re-entrant" used to mean to a CICS COBOL programmer, but it's close.)
Anyway, suppose you pop a large ABAP OO tree the correct way - with just the root and its immediate children in the node table.  (Then as the user clicks on an expandable folder, you find its children and insert them, etc.)
Then you have to be very very careful if the tree is docked on a screen with its own PBO, because the PBO will actually fire each time you click on a folder to expand it.
Why do you have to be careful? 
Well, suppose you're in the situation I was telling Rich and Max about - where the user can back out of the tree screen and come back into it with a different "root" selection.
Then you have to distinguish between two different cases in which the PBO will fire - the case where you want to pop a brand-new tree and the case where you want to continue pop new levels of an existing tree.
As I said, it never occurred to me that the screen PBO would have to fire each time the user did nothing else except expand a folder in a tree on the screen.
So I thought this might not occur to others as well, and that's why I'm mentioning it while we're sitting here having coffee.

Answer 1

I never had any issues getting my ATI card to work under linux. The new ATI drivers are much improved over the previous version.  Yes, I had to recompile the kernel so that AGPGART was a module but that isn't such big of a deal. I first installed the ATI drivers under Slack w/o any sort of package management using rpm2tgz.
The one thing that bugs most people about the ATI linux drivers isn't that the module is difficult to install but that the performance isn't up to par with their windows offerings. nVidia drivers are very close on both platforms. If I had a newer ATI card I'd probably stick with it before putting up more money to get an nVidia card (get an older GeForce 4 Ti or GeForce 6) right now. But, I'll probably always buy nVidia for future graphics cards. When I build my AMD64 box down the road it will be powered by nVidia graphics unless ATI improves by vast amounts in the driver department. FYI, I'm using an nVidia GeForce FX 5700 my current Athlon XP box and it isn't even close to being the card my old Radeon 8500 is for Windows, but under linux it's much better.