Virtualtreeview : Tbutton.visible

[jfarissi]

hello,

I need when I click in the node(see the picture) with child(level 1 or 2..) render tbutton.visible = true(expand) or false(collapse)

with this code i have an exception

Delphi-Quellcode:

procedure HasDuplicateChecked(bVisible : boolean;Node: PVirtualNode);
Var
  ParentNode, ChildNode,ChildNode1: PVirtualNode;
  I, J: Integer;
   nbData: TNodeData;
Begin
    ParentNode := node;
    ChildNode := ParentNode.FirstChild;
    for i := 0 to ParentNode.ChildCount - 1 do
    begin
        ChildNode1 := ChildNode.FirstChild;
        if editVST.HasChildren[ChildNode]= true  then
        begin
          for J := 0 to ChildNode.ChildCount - 1 do
          begin

            nbData:=TNodeData(editVST.GetNodeData(ChildNode1)^);
            if nbData.Column6 <> nil then
              nbData.Column6.Visible := bVisible;
            ChildNode1 := ChildNode.NextSibling;
          end;
        end
        else
        begin
            nbData:=TNodeData(editVST.GetNodeData(ChildNode)^);
            if nbData.Column6 <> nil then
              nbData.Column6.Visible := bVisible;
        end;
      ChildNode := ChildNode.NextSibling;
    end;
End;

any idea ?

Thanks