Højreclik i TreeView

Jeg bruger OnMouse Down

procedure TFrameTree.tvIntMouseDown(Sender: TObject; Button: TMouseButton;
  Shift: TShiftState; X, Y: Integer);
var
  aTreeView: TTreeView;
begin
  if Sender is TTreeView then
  begin
    aTreeView:= Sender as TTreeView;
    if Button = mbLeft then
      ShowMessage('Left mouse ' +  aTreeView.Selected.Text);
    if Button = mbRight then
      ShowMessage('Right mouse '+ aTreeView.Selected.Text);
  end;
end;

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