Following code demonstrates how to minimize and restore Delphi/BCB forms (or whole application if acTrayIcon component dropped to the main form) from the system tray area.

procedure TForm1.MinimizeButtonClick(Sender: TObject);
begin
  acTrayIcon1.MinimizeToTray;
end;

procedure TForm1.acTrayIconDblClick(Sender: TObject);
begin
  acTrayIcon1.RestoreFromTray;
end;