Hello,
I'm learning Java ME, remember that i'm already a Java developer, but i want to create another form to show all the details of the contact, like that of the contact book of the cell phones, here is my code:

package contacts;
import java.io.*;
import java.util.Vector;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;
import javax.microedition.rms.*;
import javax.microedition.lcdui.*;

public class simplecontacts extends MIDlet implements CommandListener {
	private Display display;
	private Alert alerta;
	private Form initialScreen, addReg;
	private TextField name, telefone;
	private Command exit, add, back, save, clear;
	private RecordStore rs = null;
	String type, message;
	boolean recordOK = false;
	private ChoiceGroup contact_type;
	private String[] listType = {"Amigos", "Família", "Trabalho", "Teste"};
	private Form listReg;
	private Command list, delete, ord, filter;
	private ChoiceGroup listRegistrys;
	boolean deletedFlags[] = null;
	private Vector vecNames;
	
	public simplecontacts() {
		display = Display.getDisplay(this);
		exit = new Command("Exit", Command.EXIT, 0);
		add = new Command("Add Registrys", Command.SCREEN, 1);
		clear = new Command("Clear Registrys", Command.SCREEN, 1);
		back = new Command("Back", Command.SCREEN, 1);
		save = new Command("Save Registry", Command.SCREEN, 1);
		name = new TextField("Name:", "", 20, TextField.ANY);
		telefone = new TextField("Telefone:", "", 10, TextField.PHONENUMBER);
		list = new Command("List Registrys", Command.SCREEN, 1);
		listRegistrys = new ChoiceGroup("Registrys", ChoiceGroup.MULTIPLE);
		vecNames = new Vector();
		delete = new Command("Delete Registrys", Command.SCREEN, 1);
		ord = new Command("Order Registrys", Command.SCREEN, 1);
		filter = new Command("Filter Registrys", Command.SCREEN, 1);
		
		initialScreen = new Form("Simple Contacts");
		initialScreen.addCommand(exit);
		initialScreen.addCommand(add);
		initialScreen.addCommand(clear);
		initialScreen.addCommand(list);
		initialScreen.addCommand(ord);
		initialScreen.addCommand(filter);
		initialScreen.addCommand(clear);
		initialScreen.setCommandListener(this);
		addReg = new Form("Add Contact");
		contact_type = new ChoiceGroup("Types", Choice.POPUP, listType, null);
		addReg.append(name);
		addReg.append(telefone);
		addReg.append(contact_type);
		addReg.addCommand(save);
		addReg.addCommand(back);
		addReg.setCommandListener(this);
		listReg = new Form("");
		listReg.append(listRegistrys);
		listReg.addCommand(delete);
		listReg.addCommand(back);
		listReg.setCommandListener(this);
		
	}

	protected void destroyApp(boolean arg0) {
		notifyDestroyed();
	}

	protected void pauseApp() {

	}

	protected void startApp() throws MIDletStateChangeException {
		try {
			rs = RecordStore.openRecordStore("SContacts", true);
		} catch (Exception exc) {
			mostrarAlerta("Erro ao abrir o RecordStore -", exc.toString());
		}
		display.setCurrent(initialScreen);
	}
	
	private void gerarTela(Vector nomes, int totalElementos) {
		for (int i = listRegistrys.size(); i > 0; i--)
			listRegistrys.delete(i - 1);
		for (int i = 0; i < nomes.size(); i++) {
			Nomes item = (Nomes) vecNames.elementAt(i);
			String nome = item.getNome();
			String telefone = item.getTelefone();
			listRegistrys.append(nome + " " + telefone, null);
		}
		display.setCurrent(listReg);
	}
	
	private void listarRegistros(FiltroNome f, ComparadorNome c) {
		RecordEnumeration rEnum = null;
		vecNames.removeAllElements();
		try {
			rEnum = rs.enumerateRecords(f, c, false);
			int posicao = 0;
			while (rEnum.hasNextElement()) {
				int id = rEnum.nextRecordId();
				byte[] dados = rs.getRecord(id);
				ByteArrayInputStream BAIS =  new ByteArrayInputStream(dados);
				DataInputStream DIS = new DataInputStream(BAIS);
				String nomeLido = DIS.readUTF();
				String telefoneLido = DIS.readUTF();
				int tipo = DIS.readInt();
				Nomes itemAgenda = new Nomes(nomeLido, telefoneLido, tipo, id, posicao);
				vecNames.addElement(itemAgenda);
				posicao++;
			}
			gerarTela(vecNames, rEnum.numRecords());
		} catch (Exception exc) {
			mostrarAlerta("Erro na listagem -", exc.toString());
		} finally {
			rEnum.destroy();
		}
	}
	
	private void apagarRegistros() {
		try {
			for (int i = 0; i < deletedFlags.length; i++) {
				if (deletedFlags[i] == true) {
					Nomes itemAgenda = (Nomes) vecNames.elementAt(i);
					try {
						rs.deleteRecord(itemAgenda.getRecordId());
					} catch (Exception exc) {
					}
				}
			}
		display.setCurrent(initialScreen);
	
		} catch (Exception exc) {
		
			Alert erro = new Alert("Nenhum registro foi selecionado -",
					"Refaça a operação ou volte para a tela inicial", null, AlertType.ERROR);
			erro.setTimeout(Alert.FOREVER);
			display.setCurrent(erro);
		}
    }
	
	private void mostrarAlerta(String tipoAlerta, String msg) {
		alerta = new Alert(tipoAlerta, msg, null, AlertType.WARNING);
		alerta.setTimeout(Alert.FOREVER);
		display.setCurrent(alerta);
	}
	
	private void adicionarRegistro() {
		try {
			ByteArrayOutputStream BAOS = new ByteArrayOutputStream();
			DataOutputStream DOS = new DataOutputStream(BAOS);
			DOS.writeUTF(name.getString());
			DOS.writeUTF(telefone.getString());
			DOS.writeInt(contact_type.getSelectedIndex());
			byte [] bRec = BAOS.toByteArray();
			rs.addRecord(bRec, 0, bRec.length);
			DOS.close();
			BAOS.close();
			display.setCurrent(initialScreen);
		} catch (Exception exc) {
			mostrarAlerta("Erro ao adicionar -", exc.toString());
		}
	}
	
	private void zerarRegistros(){
		try {
			rs.closeRecordStore();
			RecordStore.deleteRecordStore("SContacts");
			rs = RecordStore.openRecordStore("SContacts", true);
		} catch (Exception exc) {
			mostrarAlerta("Erro ao recriar o RecordStore -", exc.toString());
		}
		display.setCurrent(initialScreen);
	}
	
	public void commandAction(Command com, Displayable dis) {
		if (com == exit) {
			try {
				rs.closeRecordStore();
			} catch (Exception exc) {
				mostrarAlerta("Erro fechando o RecordStore -", exc.toString());
			}
			destroyApp(true);
		} else if (com == add) {
			name.setString("");
			telefone.setString("");
			display.setCurrent(addReg);
		} else if (com == save) {
			adicionarRegistro();
		} else if (com == clear) {
			zerarRegistros();
		} else if (com == back) {
			display.setCurrent(initialScreen);
		} else if (com == delete) {
			apagarRegistros();
		} else if (com == list) {
			listReg.setTitle("Listing All");
			listRegistrys.deleteAll();
			listarRegistros(null, null);
		} else if (com == ord) {
			listReg.setTitle("Registrys Ordened");
			listRegistrys.deleteAll();
			ComparadorNome comparador = new ComparadorNome();
			listarRegistros(null, comparador);
		} else if (com == filter) {
			listReg.setTitle("Filtred Registrys");
			listRegistrys.deleteAll();
			FiltroNome filtro = new FiltroNome("Thiago");
			ComparadorNome comparador = new ComparadorNome();
			listarRegistros(filtro, comparador);
		}
	}
}

class FiltroNome implements RecordFilter {
	String nome;
	public FiltroNome(String nomeFiltrado) {
		nome = nomeFiltrado;
	}
	
	public boolean matches(byte[] registro) {
		try {
			ByteArrayInputStream BAIS = new ByteArrayInputStream(registro);
			DataInputStream DIS = new DataInputStream(BAIS);
			String nomeLido = DIS.readUTF();
			DIS.close();
			BAIS.close();
			if (nome.compareTo(nomeLido) == 0)
				return true;
		} catch (Exception exc) {
			System.out.println("Exceção: " + exc.getMessage());
		}
		return false;
	}
}

class ComparadorNome implements RecordComparator {
	public int compare(byte[] reg1, byte[] reg2){
		try {
			ByteArrayInputStream BAIS = new ByteArrayInputStream(reg1);
			DataInputStream DIS = new DataInputStream(BAIS);
			String nome1 = DIS.readUTF();
			DIS.close();
			BAIS.close();
			ByteArrayInputStream BAIS2 = new ByteArrayInputStream(reg2);
			DataInputStream DIS2 = new DataInputStream(BAIS2);
			String nome2 = DIS2.readUTF();
			DIS2.close();
			BAIS2.close();
			if (nome1.compareTo(nome2) < 0) {
				return PRECEDES;
			} if (nome1.compareTo(nome2) > 0) {
				return FOLLOWS;
			}
		} catch (Exception exc) {
			System.out.println("Exceção: " + exc.getMessage());
		}
		return EQUIVALENT;
	}
}

class Nomes {
	private String nome, telefone;
	private int recordId;
	public Nomes(String nome, String telefone, int tipo, int recordId, int posicao) {
		this.nome = nome;
		this.telefone = telefone;
		this.recordId = recordId;
	}
	
	public String getNome() {
		return nome;
	}
	
	public String getTelefone() {
		return telefone;
	}
	
	public void setNome(String nome) {
		this.nome = nome;
	}
	
	public void setTelefone(String telefone) {
		this.telefone = telefone;
	}
	
	public int getRecordId() {
		return recordId;
	}
}

What i have to do?

Thanks,
Nathan Paulino Campos

The application that i'm developing is a simple contact book and if you didn't understand very nice my previous post, i need to change my code, in the list registry's form an option that the user can select a contact, click in a Command and it redirect the user to another form that he can see the full details about that contact that he selected, like name, telephone and type.

Thanks!

Please help me with this!!!

Two options:
A) you pass Displayable object from form to form
B) or have "magic" method changeScreen to do the job as in this MIDlet

package contacts;

import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.midlet.MIDlet;

import memo.beans.Contact;

public class ContactMIDlet extends MIDlet{

    private Display display;

    public ContactMIDlet(){}

    public void startApp(){
        display = Display.getDisplay(this);
        changeScreen(CoreUI.MAIN_MENU);
    }

    public void pauseApp(){}

    public void destroyApp(boolean unconditional){}

    public void quitApp(){
        destroyApp(true);
        notifyDestroyed();
    }

    /**
     * Method to simplify movement from screen to screen
     * @param _uiClass specifies name of class to be used
     * as declared in the CoreUI interface
     */
    public void changeScreen(String _uiClass) {
        Displayable displayable;
        try {
            displayable = (Displayable) Class.forName(_uiClass).newInstance();
            ((CoreUI) displayable).setUIManager(this);
            display.setCurrent(displayable);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Overloaded method of changeScreen just pop-up any alerts as need it.
     * @param d
     */
    public void changeScreen(Displayable d){
        display.setCurrent(d);
    }

    public void changeScreen(String _uiClass, Contact contact) {
        Displayable displayable;
        try {
            displayable = (Displayable) Class.forName(_uiClass).newInstance();
            ((CoreUI) displayable).setUIManager(this, contact);

            display.setCurrent(displayable);
        }
        catch (Exception e) {
            e.printStackTrace();
        }
    }
}

interface CoreUI

package contacts;

import memo.beans.Memo;

public interface CoreUI {

    public final String MAIN_MENU = "contact.gui.MainMenu";
    public final String CONTACT_FORM = "contact.gui.ContactForm";
    public final String VIEW_CONTACTS = "contact.gui.ViewContacts";
    public final String EDIT_CONTACT = "contact.gui.EditContact";

    void setUIManager(ContactMIDlet _mgr);

    void setUIManager(ContactMIDlet _mgr, Contact contact);
}

where EditContact can look like this for start

public class EditContact extends Form implements CoreUI, CommandListener {

    private ContactMIDlet mgr;
    private Contact contact;
    private Command backCommand,  exitCommand,  saveCommand;

    /**
     * Default constructor
     */
    public EditContact() {
        super("Add Contact");
    }

    public void setUIManager(ContactMIDlet _mgr) {}

    public void setUIManager(ContactMIDlet _mgr, Contact contact){
        this.mgr = _mgr;
        this.contact = contact;
        initScreen(); //Show the form
    }

    /**
     * Method to implement this form GUI
     */
    private void initScreen() {

    // REST OF THE CODE
    }
}
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