Sorting a grid but limited to all but the last row

[obones]

Hello,

I have a VST in grid mode onto which I attached an OnCompareNodes event to compare my nodes.
I also set hoHeaderClickAutoSort inside Header.Options

With this, when the user clicks on any of the column headers, the rows are sorted automatically which is good.

However, there is a "special row" in this grid which should stay the last one, regardless of the sort. As it does not have any data associated to it, it was easy to write this in OnCompareNodes:

  var Data1 := Sender.GetNodeData<TData>(Node1);
  var Data2 := Sender.GetNodeData<TData>(Node2);

  if not Assigned(Data1) then
  begin
    Result := 1;
  end
  else if not Assigned(Data2) then
  begin
    Result := -1;
  end
  else
  begin
    // regular comparison of Data1 and Data2 properties
  end;

And this works quite well when sorting columns in turn as they are sorted in ascending order.
But when I click again on an already sorted column, the sort order changes and my last row moves to the top which is not desirable.
I did not see a property that would be readable during the sort to allow me adjusting the first two cases depending on ascending or descending sort.
I also did not see a way to tell the last row is not to be considered in sort operations.

Would that be at all possible?

[joachimmarder]

Maybe a footer would help you as requested in issue #962. There is an open task for me to review this footer implementation:
https://github.com/eivindbakkestuen/Virtual-TreeView/tree/branch-footers

I would be grateful if you could take a look and give me a recommendation if the implementation looks promising and solves your problem.