procedure TForm1.TreeView1ContextPopup(Sender: TObject; MousePos: TPoint;
var Handled: Boolean);
var
tn : TTreeNode;
begin
tn:=TreeView1.GetNodeAt(MousePos.X,MousePos.Y);
if tn<>nil then TreeView1.Selected:=tn
else
begin
Handled:=True; Exit;
end;
if tn.Text='aaa' then
begin
TreeView1.PopupMenu:=PopupMenu1;
end;
if tn.Text='bbb' then
begin
TreeView1.PopupMenu:=PopupMenu2;
end;
...
end;