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Hello,
We have a dialog that displays list of files with checkbox to let users select which files to download.
The list view control ATLControls::CListViewCtrl is used. When displaying the dialog, we iterate through each file in the list, and based on some condition we either tick the checkbox or not using ListView_SetCheckState.
For around 1000 files ListView_SetCheckState takes 2 to 3 seconds on our system and same files take 44 seconds on customer system.
dependencywalker shows comctl32.dll is different between ours and customer systems.
Version of comctl32.dll from our system as shown by dependencywalker
C:\Windows\WinSxS\x86_microsoft.windows.common-controls_6595b64144ccf1df_5.82.22621.608_none_42d541138da2ebd2\comctl32.dll"
Version of comctl32.dll from customer system as shown by dependencywalker
c:\windows\winsxs\x86_microsoft.windows.common-controls_6595b64144ccf1df_5.82.19041.1110_none_c0da534e38c01f4d\COMCTL32.DLL
Customer system has older version of files. Could this be the reason for performance difference? If yes how to get the system updated with latest dlls? Are these dlls part of some windows update?
Customer is running Windows 10 version 21H1 (OS Build 19043.2364). Our system has Windows 11 version 22H2 (OS Build 22621.963)
Thank You,
Rakesh
[...] we iterate through each file in the list [...]
Maybe the problem is caused by slow disk operations on customer system?
There is no physical file read operation in the loop. The loop just goes through each record in the list control. (by "iterating through each file in the list" I meant "iterating through each item in the list control". (each list item represents a file but no file I/O is performed in the loop).
Did you check if a simple iteration is slow too even if ListView_SetCheckState is not called?
Maybe you should keep the list of the files separately and try a "Virtual List-View Control".
The loop that calls ListView_SetCheckState + some logic, for each item in the list takes 28 seconds. (Total 1000 items)
I comment just the line ListView_SetCheckState and the entire loop completes in 0.3 seconds.
The list control already uses virtual list style.
If the control is virtual, then maybe ListView_SetCheckState (for changing checkboxes) can be avoided.
Can you point me to a source that explains how to change checkboxes without using ListView_SetCheckState ?
Could the difference in comctll32.dll be reason for this performance issue?
Hi @rakesh sharma ,
Could the difference in comctll32.dll be reason for this performance issue?
Regarding this issue, I suggest you give feedback in this link.