TAdvTreeView: Nodes in view area stay empty at scrolling

VCL TMS VCL UI Pack
1

Sometime I have the problem that texts of nodes aren't displayed properly in the treeview: The text is empty or invisible.
So far I wasn't able to reproduce that behavior reliable in a smaller test program.

I created a little movie from my project (all data displayed are demo data).
What happens:

  • TAdvTreeview is populated
  • Alle nodes are expanded using the context menu:
    TVSelectionAdv1.BeginUpdate;
    TVSelectionAdv1.ExpandAll;
    TVSelectionAdv1.EndUpdate;
    for C := 0 to TVSelectionAdv1.Columns.Count-1 do
      TVSelectionAdv1.AutoSizeColumn(C);

Afterwards I use the mouse to scroll down in the treeview. The nodes which should appear stay empty:
27-11-2023_12-29-26

The texts are displayed when I scroll back a little bit upwards: All nodes in the view area become visible.
It seems that:

  • all nodes stay one time invisible and appear after scrolling back again.
  • if a node's text was displayed once, it will displayed properly in the future.

27-11-2023_12-59-38

Do you have an idea what causes this problem?

2

How are you populating the nodes? We couldn't reproduce this here. Can you provide a small sample demonstrating the issue?

3

As I wrote initially:

but I will try ...

4

I must have misread, my apologies. It could be related to a combination of adding/inserting nodes & beginupdate & endupdate. So a full code snippet would be welcome so we don't overlook certain properties or events that are set.

5

Meanwhile I spent hours to reproduce this in a smaller test project - no chance!

As workaround I added In my main project:

procedure TFrmOrderAssignCalendar.TVSelectionAdv1VScroll(Sender: TObject; APosition: Single);
begin
  TVSelectionAdv1.BeginUpdate;
  TVSelectionAdv1.EndUpdate;
end;

I will send a report if I have a better idea.