Algorithm for finding end of a list (SAP GUI) - vba

Question

I'm writing a script that adds elements to a list in a SAP GUI screen. Now, it seems that when using SAP GUI, nothing "exists" unless it is actually on screen, so the first step involves finding the end of the list.
I accomplished this by scrolling though each element, and checking if it was blank.
Do While Not blank
If session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010/ctxtMAPL-MATNR[2,0]").Text = "" Then blank = True
session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010").verticalScrollbar.Position = i
i = i + 1
Loop
However, for very large existing lists, this takes a long time. I'm trying to figure out a way to find the end more quickly. Some truths/limitations I know:
I'm assuming I have no knowledge of the list length.
I cannot command the verticalScrollbar.position too far beyond the end of
the list. For ex. if the list contains 62 elements, .verticalScrollbar.Position = 100 will not work.
In the case of the above example, SAP does NOT throw an error. Nothing happens at all, and then next line of code executes.
All references to elements are with respect to their position on the screen. Ex, if I scroll down 5 positions, the 6th element of the overall list would actually indexed as 1.
On the other hand, verticalScrollbar.Position is absolute
I'm thinking of doing the following (in very psuedocode):
i = 0
do while scrolled = true
scrolled = false
a = GUIlist[0]
verticalScrollbar.Position = i + 1000
b = GUIlist[0]
'check to see the first element shown has changed
if a <> b then
scrolled = true
i = i + 1000
end if
loop
do while scrolled = true
scrolled = false
a = GUIlist[0]
verticalScrollbar.Position = i + 500
b = GUIlist[0]
if a <> b then
scrolled = true
i = i + 500
end if
loop
...and so on until I'm iterating i by one.
Is there a generally accepted better way of doing this kind of 'search'?
Any input is appreciated.
Thanks

Answer 1

My suggestion:
session.findById("wnd[0]").sendVKey 83
myPosition = session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010").verticalScrollbar.Position
do
if session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010/ctxtMAPL-MATNR[2,0]").Text = "" then exit do
myPosition = myPosition + 1
session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010").verticalScrollbar.Position = myPosition
loop
msgbox myPosition
Regards,
ScriptMan

Answer 2

Just to go to the end
max_scrollbar = session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010").verticalScrollbar.Maximum ' Get the maximum scrollbar value
session.findById("wnd[1]/usr/tblSAPLCZDITCTRL_4010").verticalScrollbar.Position = max_scrollbar ' Go to the end