Filter-Dropdown-Performance with >20k entries? (possible Codechange suggestion + question)

[Janecek_David]

In our grid there is a column, which has around 30k different entries. We have set "FilterDropDownAuto=true". If we open the filtering, the dropdown takes ages to open and if we click on an entry in the Dropdown-Filter it again takes a while and then just closes the filter.

One reason for that might be:
In "TAdvStringGrid.GetFilter()" there is a stringlist "chklist" (Line 14646 in AdvGrid.pas) which only checks, if an entry has already been added.I think there would be a good performance increase, if you use a tdictionary<String, x> or thashset for that. Also the ".sorted = true" of the Stringlist doesnt seem to do anything, or?

Otherwise: do you have any example of a "working" grid, which has several thousand of entries in a column-dropdown and works quite well?

Thanks!

[brunofierens]

We investigated this and the performance issue is not in this part.
We've seen that the performance issue is related to
FFilterList.CustomSort(StringListCompareLogical);
which is used to perrform sorting taking numeric values in account instead of plain alphabetical sort.
We now made the algorithm smarter and that leads to a significant performance improvement. This improvement will be in the next release.

[Janecek_David]

Great! Thank you very much for the quick answer and solution!