Ações dos botões J2Me em várias telas

/*
package textfield;

import javax.microedition.midlet.MIDlet;
import javax.microedition.lcdui.*;
/**
 * The text field demo displays all of the text field types on the screen
 * allowing the user to edit them at will.
 *
 * @version 2.0
 */

public class TextFieldDemo extends MIDlet implements CommandListener {

    private final static Command exitCommand	= new Command("Exit",		Command.EXIT, 1);
    private final static Command localizar		= new Command("Localizar",  Command.SCREEN, 1);
	private final static Command voltar			= new Command("Voltar",		Command.SCREEN, 1);

    
    private boolean firstTime;
    
    private Form mainForm;
	private Form outroForm;
	private Form form2;
    
    public TextFieldDemo() {
        firstTime	= true;
    }
    
    protected void startApp() {
        if (firstTime) {

        mainForm	= new Form("Text Field");
		outroForm	= new Form("Outro Form");
		form2		= new Form("Form 2");

            mainForm.append("This demo contains text fields each one " +
                    "with a different constraint");
    
            mainForm.append(
	            new TextField("Any Character", "", 15, TextField.ANY));
            mainForm.append(
		    new TextField("E-Mail", "", 15, TextField.EMAILADDR));
            mainForm.append(new TextField("Number", "", 15, TextField.NUMERIC));
            mainForm.append(
                    new TextField("Decimal", "", 15, TextField.DECIMAL));
            mainForm.append(
                    new TextField("Phone", "", 15, TextField.PHONENUMBER));
            mainForm.append(
                    new TextField("Password", "", 15, TextField.PASSWORD));
            mainForm.append(new TextField("URL", "", 15, TextField.URL));
            
            mainForm.addCommand(exitCommand);
			mainForm.addCommand(localizar);
            mainForm.setCommandListener(this);
            firstTime = false;
        }
        Display.getDisplay(this).setCurrent(mainForm);
    }
    
    public void commandAction(Command c, Displayable s) {
	if (c == exitCommand) {
	    destroyApp(false);
	    notifyDestroyed();
	}else
		if( c == localizar){
			outroForm.append(new TextField("Qualquer Coisa",	"", 15, TextField.ANY));
			outroForm.append(new TextField("Outra Coisa",		"", 15, TextField.ANY));
			outroForm.append(new TextField("Mais Outra Coisa",	"", 15, TextField.ANY));
			outroForm.addCommand(exitCommand);
			outroForm.addCommand(voltar);
			Display.getDisplay(this).setCurrent(outroForm);
		}else
			if( c == voltar){
				form2.append(new TextField("Qualquer Coisa 2",	"", 15, TextField.ANY));
				form2.append(new TextField("Outra Coisa 2",		"", 15, TextField.ANY));
				form2.append(new TextField("Mais Outra Coisa 2",	"", 15, TextField.ANY));
				Display.getDisplay(this).setCurrent(form2);
			}
    }
    
    protected void destroyApp(boolean unconditional) {
    }
    
    protected void pauseApp() {
    }


}