public void actionPerformed(ActionEvent event) {
   if (event.getActionCommand().matches("mainmenu")) {
     update("main");
   } else if (event.getActionCommand().matches("loadShipment")) {
     update("loadShipment");
   } else if (event.getActionCommand().matches("pickup")) {
     if (shipmentTable.getSelectedRowCount() != 0) {
       driverService.pickupShipment(driver, shipmentList.get(shipmentTable.getSelectedRow()));
       update("main");
     }
     update();
   } else if (event.getActionCommand().matches("reportloc")) {
     update("reportloc");
   } else if (event.getActionCommand().matches("report")) {
     driverService.reportLocation(driver, (Location) locationComboBox.getSelectedItem());
     update("main");
   } else if (event.getActionCommand().matches("logout")) {
     loginUserInterface.update("main");
     graphicPanel = null;
   } else if (event.getActionCommand().matches("update")) {
     update();
   }
 }