[icWasya]

Ну например вынести это в отдельную процедуру

Код:

procedure TForm1.AddChildrens(Node:TTreeNode;ChildrenNames:TStrings;ImageIndex:Integer);
var
  ChildrenName : String;
  NewItem:TTreeNode;
begin
   cxTreeView1.Items.BeginUpdate; 
   if Node = Nil then
      cxTreeView1.Items.Clear;
   else
      Node.DeleteChildren;
   for ChildrenName in ChildrenNames do
   begin
      NewItem := cxTreeView1.Items.AddChild(Node,ChildrenName );
      NewItem.ImageIndex := ImageIndex;
      NewItem.SelectedIndex := ImageIndex;
   end;
   cxTreeView1.Items.EndUpdate;
end;