echoclientmidlet.java

Bluetooth echo between pc server and client

// EchoClientMIDlet.java
// Andrew Davison, [e-mail], August 2005

/* This screen starts the device and services search, and reports 
   its ongoing status. At the end of the search, a services 
   list screen (ServicesList) is displayed.

   A service is chosen from the list, and a form allows the user to 
   send messages and receive echoed responses from the server.
   The echoed messages are changed to uppercase.
*/


import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.util.*;


public class EchoClientMIDlet extends MIDlet 
                                  implements CommandListener 
{
  // UUID and name of the echo service
  private static final String UUID_STRING = "11111111111111111111111111111111";
         // 32 hex digit string (will become 128 bit ID)

  private static final String SERVICE_NAME = "echoserver";   // use lowercase

  // GUI elements
  private Form form;
  private Gauge searchGauge;
  private int gaugeIndex;
  private StringItem statusSI;
  private Command exitCmd;

  private Display display;

  private ServiceFinder serviceFinder;


  public EchoClientMIDlet() 
  {
    // build GUI
    form = new Form("Searching");

    exitCmd = new Command("Exit", Command.EXIT, 1);
    form.addCommand(exitCmd);
 
    statusSI = new StringItem("Status: ", "Starting...");
    searchGauge = new Gauge("Bluetooth Service Search", false,
                         Gauge.INDEFINITE, Gauge.CONTINUOUS_RUNNING);
    form.append(statusSI);
    gaugeIndex = form.append(searchGauge); 

    form.setCommandListener(this);

    // start searching for services
    serviceFinder = new ServiceFinder(this, UUID_STRING, SERVICE_NAME);
  } // end of EchoClientMIDlet()


  protected void startApp() 
  { display = Display.getDisplay(this);
    display.setCurrent(form);
  } // end of startApp()

  protected void pauseApp() {}

  protected void destroyApp(boolean unconditional) 
  // callable from here, ServicesList, and ClientForm
  { notifyDestroyed(); }


  public void commandAction(Command c, Displayable d) 
  { if (c == exitCmd)
      destroyApp(true);
  }  // end of commandAction()


  // ----------------- reporting from ServiceFinder --------------


  public void setStatus(String msg)
  { statusSI.setText(msg);  }


  public void searchError(String msg)
  // show error message and remove gauge
  { statusSI.setText(msg);
    searchGauge.setValue(Gauge.CONTINUOUS_IDLE);
    form.delete(gaugeIndex); 
  } // end of searchError()


  public void showServices(Hashtable searchTable)
  // show the services list screen, so the user can choose a service
  { ServicesList sl = new ServicesList(searchTable, this, display);
    display.setCurrent(sl);
  }

} // end fo EchoClientMIDlet class