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The final step is to ask handle the yes/no button click. If yes is pressed, we must open the database and write the contact (received XML) as a new record. If no is pressed, we repaint the screen with the "Waiting for contact information…" message. As we've already seen, button clicks are handled by overriding the com.sun.kjava.Spotlet.penDown() event handler. If the exit button has been pressed, we register our "owner" — the ContactBook object — as the current Spotlet event listener (remember, there is only one Spotlet listening for events at a time), and tell ContactBook to paint itself. This effectively hands control back to the main menu. The owner is set in the ReceiveContact constructor:

import com.sun.kjava.*;
import nanoxml.kXMLElement;
import nanoxml.XMLParseException;

public class ReceiveContact extends Spotlet {

  private Button exitBtn = new Button("Quit", 135, 140),
    yesBtn, noBtn;
  private Graphics g = Graphics.getGraphics();
  private ContactBook owner;
  private String contact;

  public ReceiveContact(ContactBook owner) {
    register(NO_EVENT_OPTIONS);
    this.owner = owner;
    paint(); //paint the "Waiting for..." message
}

  public void penDown(int x, int y) {
    //did the user press the exit btn?
    if (exitBtn.pressed(x,y)) {
      owner.register(NO_EVENT_OPTIONS);
      owner.paint();
    }
    //did the user press the yes btn, telling us to
    //write the received contact into the database?
    else if (yesBtn.pressed(x,y))     {
      Database db = new Database(ContactBook.dbType,
        ContactBook.creatorId, Database.WRITEONLY);
      if (!db.isOpen()){ 
        //the database doesn't exist yet. create it.
        Database.create(0, ContactBook.dbName,
          ContactBook.creatorId, ContactBook.dbType, false);
        db = new Database(ContactBook.dbType,
          ContactBook.creatorId, Database.WRITEONLY);
      }
      db.addRecord(contact.getBytes());
      db.close();
      paint(); //repaint the "Waiting for..." message
    }
    else if (noBtn.pressed(x,y))
      paint();
  }

  public void beamReceive(byte[] buf) {
    //parse the received xml using NanoXML

    contact = new String(buf);
    kXMLElement elem = new kXMLElement();
    try     {
      elem.parseString(contact);
    }
    catch (XMLParseException e)     {
      //can't parse received data--the sender probably
      //wasn't BeamContact!! ignore it and return.
      paint();
    
 
      return;
    }
    String fname = elem.getProperty("fname"), 
      lname = elem.getProperty("lname");
    if (fname != null && lname != null)     {
      g.clearScreen();
      g.drawString("Contact info was received for:", 0, 20);
      g.drawString(fname + " " + lname, 0, 40);
      g.drawString("Import into contact book?", 0, 60);
      yesBtn = new Button("Yes", 40, 80);
      noBtn = new Button("No", 60, 80);
      yesBtn.paint();
      noBtn.paint();
    }
    else
      paint();
  }

  public void paint() {
    g.clearScreen();
    yesBtn = noBtn = null;
    exitBtn.paint();
    g.drawString("Waiting for contact information...", 10,
      70);
  }
}