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I tried to convert a ListView in LargeIcon view to a FastObjectListView that uses groups. The code throws an exception while trying to define the groups:

"When the ListView is in virtual mode, you cannot enumerate through the ListView items collection using an enumerator or call GetEnumerator. Use the ListView items indexer instead and access an item by index value."

The exception occurs on this line in the code:

channellistView.Groups.Add(new ListViewGroup(category.name, HorizontalAlignment.Left));

I am adding the groups programmatically in the code. I set the flag 'ShowGroups' to true.

Is this possible? How can I add groups to a FastObjectListView in LargeIcon view? Is there a code sample or recipe?

When I used MoveObjects() with an index of 0 with a collection of objects that includes the first object (at index 0), I get an IndexOutOfRangeException because it will try to insert objects at index -1.

I narrowed it down to this block of code in MoveObjects():

Since, the first object (at index 0) will satisfy the if condition, the index will be decreased from 0 to -1.
Should this condition be changed to if (i >= 0 && i < index) instead?

I have a FastObjectListView with its custom Sort() defined within its VirtualListDataSource. The issue I'm facing is that even if I set the SortOrder of the FOLV to SortOrder.None, it will still attempt to sort in ascending order whenever any addition / deletion occurs.

I saw that insertion and deletion of objects will always attempt to sort and I followed the issue to this block of code:

When line 8358 executes, args.SortOrder will be set to SortOrder.Ascending even if the parameter order is set to SortOrder.None due to this block of code:

Therefore, execution will reach line 8378 and the CustomSorter will be provided a SortOrder of Ascending instead of None.

I set IsButtton = true, and rendder image.
Listview not show image.
Button i set IsButton = false => Listview show image.
How to use icon in button.

Thanks you so much

It seems like sorting and filtering only work on non-icon view styles of the listview. Is this correct?

I worked on this problem for a few weeks.....(Demo is working)
You can get my fork and test project to see result. address on the bottom

Problem with new project: When I'm bringing object from ToolBox to new form/control (DataListView, FastDataListView) I can't make IsButtom column look like button. It seems rendering is not working, Can't make filter work (almost duplicate code from the samples, not working)

Properties can't be set in designer mode:
CellPadding- Can't be set at Column properties "Text "text" cannot be parsed. The expected text format is "1"."
Fork @
https://github.com/StrannikVK/ObjectListView2020.git
Test Project:
ObjectListViewTools2020.csproj

How do you make the cell editable, but it's read-only?
Because I only want the user to copy the cell content and not modify it.

Since, VirtualObjectListView and FastObjectListView are Virtual ListViews, the column auto-resize methods both on the ColumnHeader and ListView levels do not work correctly.

They simply auto-resize based on the current visible objects, not all of them.

Hello, Thanks for fixing the performance issue. However, TreeListView lines and some other graphics elements are not drawn. Was removing them a necessary compromise to attain better performance?

Hello,

are you able to resolve the scrolling performance issue mentioned in these threads of the original control ?

https://sourceforge.net/p/objectlistview/discussion/812922/thread/1d466b3b75/

Your ObjectListView fork suffers from the same Problem

Test case : FastObjectListview : 10 text columns, 1000 rows with a hardcoded most simple aspectgetter - a simple string

To create the Problem - Hold the Keyboard down arrow and watch what happens in Task Manager when the control needs to scroll. CPU Time maxes out on the main UI thread. The videos in the link above show the problem as well. Scrolling goes lines by line and UI Thread is locked so bad that no other meaningful operations can be performed when the down/up arrows are kept pressed and the control is scrolling.

Try the same with 20 columns and the control becomes unusable and is anything but "fast"

Try disabling all columns (hide) and leave only the first - scroll now...that is the desired scroll performance.

I am willing to make a donation to the Person/Team that can make a super responsive FastObjectListview (using the base ObjectListview 2.9.1+ code/features) that has no scrolling problem with 20 columns

Thank you kindly

The only reason my team currently does not use this is because it does not have builds for .NET Core 3.1 / .NET 5