Java/J2ME/List

Implicit List

/*--------------------------------------------------
* ImplicitList.java
*
* Example from the book:     Core J2ME Technology
* Copyright John W. Muchow   http://www.CoreJ2ME.ru
* You may use/modify for any non-commercial purpose
*-------------------------------------------------*/
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class ImplicitList extends MIDlet implements CommandListener
{
  private Display display;      // Reference to Display object
  private List lsDocument;     // Main list
  private Command cmExit;      // Command to exit
  private Command cmAdd;       // Command to add an element
  
  public ImplicitList()
  {
    display = Display.getDisplay(this);
    // Create the Commands
    cmExit = new Command("Exit", Command.EXIT, 1);
    cmAdd = new Command("Add", Command.SCREEN, 1);
    try 
    { 
      // Create array of image objects
      Image images[] = {Image.createImage("/ff.png"), 
                        Image.createImage("/rr.png"),
                        Image.createImage("/new.png")};            
                        
      // Create array of corresponding string objects                                                
      String options[] = {" Next", " Previous", " New"};          
      // Create list using arrays, add commands, listen for events
      lsDocument = new List("Document Option:", 
                             List.IMPLICIT, options, images); 
      lsDocument.addCommand(cmExit);
      lsDocument.addCommand(cmAdd);
      lsDocument.setCommandListener(this);
    }
    catch (java.io.IOException e)
    {
      System.err.println("Unable to locate or read .png file");
    }
  }
      
  public void startApp() 
  {
    display.setCurrent(lsDocument);
  }
  
  public void pauseApp()
  {
  }
     
  public void destroyApp(boolean unconditional)
  {
  }
  public void commandAction(Command c, Displayable s)
  {
    // If an implicit list generated the event
    if (c == List.SELECT_COMMAND)
    {
      switch (lsDocument.getSelectedIndex())
      {
        case 0:
          System.out.println("Next");
          break;
  
        case 1:
          System.out.println("Previous");
          break;
          
        case 2:
          System.out.println("New");
          break;        
        default:
          System.out.println("New Element");
      }
    }
    else if (c == cmAdd)
    {
      try
      {
        
        System.out.println("lsDocument.size():" + lsDocument.size());
        // Add a new element. Using size() as the insertion point,
        // the element will appended to the list.
        lsDocument.insert(lsDocument.size(), " Delete ", 
                           Image.createImage("/delete.png"));
      }
      catch (java.io.IOException e)
      {
        System.err.println("Unable to locate or read .png file");
      } 
    }
    else if (c == cmExit)
    {
      destroyApp(false);
      notifyDestroyed();
    } 
  }
}

List CheckBox

//jad file (please verify the jar size)
/*
MIDlet-Name: ListCheckBox
MIDlet-Version: 1.0
MIDlet-Vendor: MyCompany
MIDlet-Jar-URL: ListCheckBox.jar
MIDlet-1: ListCheckBox, , ListCheckBox
MicroEdition-Configuration: CLDC-1.0
MicroEdition-Profile: MIDP-1.0
MIDlet-JAR-SIZE: 100
*/
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.List;
import javax.microedition.midlet.MIDlet;
public class ListCheckBox extends MIDlet implements CommandListener {
  private Display display;
  private Command exit = new Command("Exit", Command.EXIT, 1);
  private Command submit = new Command("Submit", Command.SCREEN, 2);
  private List list = new List("Select Media", List.MULTIPLE);
  public ListCheckBox() {
    display = Display.getDisplay(this);
    list.append("Books", null);
    list.append("Movies", null);
    list.append("Television", null);
    list.append("Radio", null);
    list.addCommand(exit);
    list.addCommand(submit);
    list.setCommandListener(this);
  }
  public void startApp() {
    display.setCurrent(list);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command command, Displayable Displayable) {
    if (command == submit) {
      boolean choice[] = new boolean[list.size()];
      StringBuffer message = new StringBuffer();
      list.getSelectedFlags(choice);
      for (int i = 0; i < choice.length; i++) {
        if (choice[i]) {
          message.append(list.getString(i));
          message.append(" ");
        }
      }
      Alert alert = new Alert("Choice", message.toString(), null, null);
      alert.setTimeout(Alert.FOREVER);
      alert.setType(AlertType.INFO);
      display.setCurrent(alert);
      list.removeCommand(submit);
    } else if (command == exit) {
      destroyApp(false);
      notifyDestroyed();
    }
  }
}

List Demo

/* License
 * 
 * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *  
 *  * Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
 *  * Redistribution in binary form must reproduce the above copyright notice,
 *      this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of Sun Microsystems, Inc. or the names of contributors
 * may be used to endorse or promote products derived from this software
 * without specific prior written permission.
 *  
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *  
 * You acknowledge that this software is not designed, licensed or intended
 * for use in the design, construction, operation or maintenance of any
 * nuclear facility. 
 */
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
public class ListDemoMIDlet extends MIDlet {
    private Display              display;
    private int                  mode = List.IMPLICIT;
    private Command exitCommand = new Command( "Exit",
                                   Command.SCREEN, 2 );
    private Command selectCommand = new Command( "Select",
                                       Command.OK, 1 );
    private Command nextCommand = new Command( "Next",
                                   Command.SCREEN, 2 );
    public ListDemoMIDlet(){
    }
    protected void destroyApp( boolean unconditional )
                   throws MIDletStateChangeException {
        exitMIDlet();
    }
    protected void pauseApp(){
    }
    protected void startApp() throws
    MIDletStateChangeException {
        if( display == null ){ // first time called...
            initMIDlet();
        }
    }
    private void initMIDlet(){
        display = Display.getDisplay( this );
        display.setCurrent( new SampleList( mode ) );
    }
    public void exitMIDlet(){
        notifyDestroyed();
    }
    public static final String[] items = {
        "First", "Second", "Third", "Fourth"
    };

    class SampleList extends List implements
                           CommandListener {
        private int mode;
        SampleList( int mode ){
            super( "", mode, items, null );
            addCommand( exitCommand );
            addCommand( selectCommand );
            addCommand( nextCommand );
            setCommandListener( this );
            switch( mode ){
                case IMPLICIT:
                    setTitle( "Implicit" );
                    break;
                case EXCLUSIVE:
                    setTitle( "Exclusive" );
                    break;
                case MULTIPLE:
                    setTitle( "Multiple" );
                    break;
            }
            this.mode = mode;
        }
        public void commandAction( Command c,
                             Displayable d ){
            if( c == exitCommand ){
                exitMIDlet();
            } else if( c == selectCommand ){
                showSelection( false );
            } else if( c == SELECT_COMMAND ){
                showSelection( true );
            } else if( c == nextCommand ){
                if( mode == List.IMPLICIT ){
                    mode = List.EXCLUSIVE;
                } else if( mode == List.EXCLUSIVE ){
                    mode = List.MULTIPLE;
                } else {
                    mode = List.IMPLICIT;
                }
                display.setCurrent( new SampleList(
                                             mode ) );
            }
        }
        private void showSelection( boolean implicit ){
            Alert alert = new Alert(
                       implicit ? "Implicit Selection"
                               : "Explicit Selection" );
            StringBuffer buf = new StringBuffer();
            if( mode == MULTIPLE ){
                boolean[] selected = new boolean[ size() ];
                getSelectedFlags( selected );
                for( int i = 0; i < selected.length; ++i ){
                    if( selected[i] ){
                        if( buf.length() == 0 ){
                            buf.append(
                             "You selected: " );
                        } else {
                            buf.append( ", " );
                        }
                        buf.append( getString( i ) );
                    }
                }
                if( buf.length() == 0 ){
                    buf.append( "No items are selected." );
                }
            } else {
                buf.append( "You selected " );
                buf.append( getString(
                       getSelectedIndex() ) );
            }
            alert.setString( buf.toString() );
            alert.setTimeout( Alert.FOREVER );
            display.setCurrent( alert,display.getCurrent() );
        }
    }
}

List Implicit

//jad file (please verify the jar size)
/*
MIDlet-Name: ListImplicit
MIDlet-Version: 1.0
MIDlet-Vendor: MyCompany
MIDlet-Jar-URL: ListImplicit.jar
MIDlet-1: ListImplicit, , ListImplicit
MicroEdition-Configuration: CLDC-1.0
MicroEdition-Profile: MIDP-1.0
MIDlet-JAR-SIZE: 100
*/
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.List;
import javax.microedition.midlet.MIDlet;
public class ListImplicit extends MIDlet implements CommandListener {
  private Display display;
  private List list = new List("Menu:", List.IMPLICIT);
  private Command exit = new Command("Exit", Command.EXIT, 1);
  Alert alert;
  public ListImplicit() {
    display = Display.getDisplay(this);
    list.append("New", null);
    list.append("Open", null);
    list.addCommand(exit);
    list.setCommandListener(this);
  }
  public void startApp() {
    display.setCurrent(list);
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  public void commandAction(Command command, Displayable displayable) {
    if (command == List.SELECT_COMMAND) {
      String selection = list.getString(list.getSelectedIndex());
      alert = new Alert("Option Selected", selection, null, null);
      alert.setTimeout(Alert.FOREVER);
      alert.setType(AlertType.INFO);
      display.setCurrent(alert);
    } else if (command == exit) {
      destroyApp(false);
      notifyDestroyed();
    }
  }
}

List Item MIDlet

/*
J2ME in a Nutshell
By Kim Topley
ISBN: 0-596-00253-X
*/
import java.io.IOException;
import java.util.Calendar;
import java.util.Date;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Choice;
import javax.microedition.lcdui.ChoiceGroup;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.DateField;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.Gauge;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.ImageItem;
import javax.microedition.lcdui.Item;
import javax.microedition.lcdui.ItemStateListener;
import javax.microedition.lcdui.List;
import javax.microedition.lcdui.Screen;
import javax.microedition.lcdui.StringItem;
import javax.microedition.lcdui.TextField;
import javax.microedition.midlet.MIDlet;
public class ItemMIDlet extends MIDlet 
        implements CommandListener, ItemStateListener {
    // The MIDlet"s Display object
    private Display display;
        
    // Flag indicating first call of startApp
    protected boolean started;
    
    // Exit command
    private Command exitCommand;
    
    // Back to examples list command
    private Command backCommand;
    
    // The example selection list
    private List examplesList;
    
    // The Screens used to demonstrate different Items
    private Screen[] screens;
    
    // The example names. Used to populate the list.
    private String[] examples = {
        "StringItem", "TextField", "DateField",
        "ImageItem", "Gauge", "ChoiceGroup",
        "List", "Alert", "Sounds"
    };
    
    // List of alert types
    private AlertType[] alertTypes = new AlertType[] {
        AlertType.ALARM, AlertType.CONFIRMATION, AlertType.ERROR,
        AlertType.INFO, AlertType.WARNING, null
    };
    
    private String[] alertTypeNames = new String[] {
        "ALARM", "CONFIRMATION", "ERROR", "INFO", "WARNING", "None"
    };
    protected void startApp() {
        if (!started) {
            started = true;
            display = Display.getDisplay(this);
            
            // Create the common commands
            createCommands();
            
            // Create the screens
            createScreens();
            
            // Create the list of examples
            createList();
            
            // Start with the List
            display.setCurrent(examplesList);
        }
    }
    protected void pauseApp() {
    }
    protected void destroyApp(boolean unconditional) {
    }
    public void commandAction(Command c, Displayable d) {
        if (d == examplesList) {
            // New example selected
            int index = examplesList.getSelectedIndex();
            display.setCurrent(screens[index]);
        } else if (c == exitCommand) {
            // Exit. No need to call destroyApp
            // because it is empty.
            notifyDestroyed();
        } else if (c == backCommand) {
            // Go back to main selection list
            display.setCurrent(examplesList);
        } else if (c == List.SELECT_COMMAND) {
            // Selection made in the IMPLICIT LIST
            handleChoiceSelection((Choice)d);
        }
    }
    
    public void itemStateChanged(Item item) {        
        if (item instanceof TextField) {
            System.out.println("Text field content: <" +
                            ((TextField)item).getString() + ">");
        } else if (item instanceof DateField) {
            DateField df = (DateField)item;
            Date date = df.getDate();
            if (date != null) {
                Calendar cal = Calendar.getInstance();
                cal.setTime(date);
                System.out.println("Date field content set to " + date);                
            } else {
                System.out.println("Date field content set to null");
            }
        } else if (item instanceof Gauge) {
            int value = ((Gauge)item).getValue();
            System.out.println("Gauge value set to " + value);
        } else if (item instanceof ChoiceGroup) {
            handleChoiceSelection((Choice)item);
        } else {
            System.out.println("Item state changed in " + item);
        }
    }    
    
    private void createCommands() {
        exitCommand = new Command("Exit", Command.EXIT, 0);
        backCommand = new Command("Back", Command.BACK, 1);
    }
    
    private void createList() {
        examplesList = new List("Select Example", List.IMPLICIT);
        for (int i = 0; i < examples.length; i++) {
            examplesList.append(examples[i], null);
        } 
        examplesList.setCommandListener(this);
    }
    
    private void createScreens() {
        screens = new Screen[examples.length];
        screens[0] = createStringsForm();
        screens[1] = createTextFieldForm();
        screens[2] = createDateFieldForm();
        screens[3] = createImageItemForm();
        screens[4] = createGaugeForm();
        screens[5] = createChoiceGroupForm();
        screens[6] = createListExample();
        screens[7] = createAlertForm();
        screens[8] = createSoundsForm();
    }
    private void addCommands(Displayable d) {
        d.addCommand(exitCommand);
        d.addCommand(backCommand);
        d.setCommandListener(this);
        if (d instanceof Form) {
            ((Form)d).setItemStateListener(this);
        }
    }
    
    // Example for StringItem
    private Form createStringsForm() {
        Form form = new Form("StringItem");
        
        form.append(new StringItem("State ", "OK"));
        form.append(new StringItem(null, "No label\n"));
        form.append(new StringItem(null, "Line\nbreak"));
        form.append(new StringItem("Label", "Text."));
        form.append(new StringItem("Label2 ", "Text2."));
        
        addCommands(form);
        return form;
    }
    
    // Example for TextField
    private Form createTextFieldForm() {
        Form form = new Form("TextField");
        
        form.append(new TextField("Any", null, 8, TextField.ANY));
        form.append(new TextField("Phone", "1234567890", 10, TextField.PHONENUMBER));
        form.append(new TextField("Number", "12345", 8, TextField.NUMERIC));
        form.append(new TextField("Password", null, 8, TextField.PASSWORD | TextField.NUMERIC));
        
        addCommands(form);
        return form;
    }
    
    // Example for DateField
    private Form createDateFieldForm() {
        Form form = new Form("DateField");
        
        // Get Calendar for the epoch date and time
        Calendar baseCal = Calendar.getInstance();
        Date baseDate = new Date(0);
        baseCal.setTime(baseDate);
        
        // Get Calendar for now and use the epoch
        // values to reset the date to the epoch.
        Calendar cal = Calendar.getInstance();
        Date now = new Date();       
        cal.setTime(now);
        cal.set(Calendar.YEAR, baseCal.get(Calendar.YEAR));
        cal.set(Calendar.MONTH, baseCal.get(Calendar.MONTH));
        cal.set(Calendar.DATE, baseCal.get(Calendar.DATE));
        
        DateField timeOnly = new DateField("Time", DateField.TIME);
        DateField dateOnly = new DateField("Date", DateField.DATE);
        DateField both = new DateField("Both", DateField.DATE_TIME);
        
        timeOnly.setDate(cal.getTime());
        dateOnly.setDate(now);
        both.setDate(now);
        
        form.append(timeOnly);
        form.append(dateOnly);
        form.append(both);
       
        addCommands(form);
        return form;
    }
    
    // Example for ImageItem
    private Form createImageItemForm() {
        Form form = new Form("ImageItem");
        
        try {
            Image red = Image.createImage("/ora/ch4/resources/red.png");
            Image blue = Image.createImage("/ora/ch4/resources/blue.png");
            // ImageItems with labels
            // (1)
            form.append(new ImageItem("Center", red, ImageItem.LAYOUT_CENTER, null));
            
            // (2)
            form.append(new ImageItem("Left", red, ImageItem.LAYOUT_LEFT, null));
            
            // (3)
            form.append(new ImageItem("Right", red, ImageItem.LAYOUT_RIGHT, null));
            
            // (4)
            form.append(new ImageItem("Default", red, ImageItem.LAYOUT_DEFAULT, null));
            
            // ImageItems with no labels
            // (5)
            form.append(new ImageItem(null, blue, 
                    ImageItem.LAYOUT_NEWLINE_BEFORE | 
                    ImageItem.LAYOUT_CENTER | 
                    ImageItem.LAYOUT_NEWLINE_AFTER, null));
            
            // (6)
            form.append(new ImageItem(null, blue, 
                    ImageItem.LAYOUT_NEWLINE_BEFORE | 
                    ImageItem.LAYOUT_DEFAULT | 
                    ImageItem.LAYOUT_NEWLINE_AFTER, null));
            
            // (7)
            form.append(new ImageItem(null, blue, 
                    ImageItem.LAYOUT_NEWLINE_BEFORE | 
                    ImageItem.LAYOUT_RIGHT | 
                    ImageItem.LAYOUT_NEWLINE_AFTER, null));
            
            // (8)
            form.append(new ImageItem(null, blue, ImageItem.LAYOUT_DEFAULT, null)); 
            form.append(new ImageItem(null, blue, ImageItem.LAYOUT_DEFAULT, null)); 
        } catch (IOException ex) {
            form.append("Failed to load images");
        }
        
        addCommands(form);
        return form;
    }
    
    // Example for Gauge
    private Form createGaugeForm() {
        Form form = new Form("Gauge");
        
        form.append(new Gauge(null, true, 100, 50));
        form.append(new Gauge(null, true, 100, 25));
        form.append(new Gauge(null, false, 100, 50));
        
        addCommands(form);
        return form;
    }
    
    // Example for ChoiceGroup
    private Form createChoiceGroupForm() {
        Form form = new Form("ChoiceGroup");
        
        try {
            Image red = Image.createImage("/ora/ch4/resources/red.png");
            Image green = Image.createImage("/ora/ch4/resources/green.png");
            Image blue = Image.createImage("/ora/ch4/resources/blue.png");
            // Exclusive choice group
            String[] strings = new String[] { "Red", "Green", "Blue" };
            Image[] images = new Image[] { red, green, blue };
            ChoiceGroup exGroup = new ChoiceGroup("Choose one", ChoiceGroup.EXCLUSIVE,
                                                        strings, images);
            form.append(exGroup);
            // Multiple choice group
            ChoiceGroup multiGroup = new ChoiceGroup("Choose any", ChoiceGroup.MULTIPLE);
            form.append(multiGroup);
            multiGroup.append("Use SSL", null);
            multiGroup.append("Reconnect on failure", null);
            multiGroup.append("Enable tracing", null);
        } catch (IOException ex) {
            form.append("Failed to load images");
        }
        
        addCommands(form);
        return form;
    }
    
    // Example for List
    private Screen createListExample() {
        List list = new List("List", List.IMPLICIT);
        try {
            Image red = Image.createImage("/ora/ch4/resources/red.png");
            Image green = Image.createImage("/ora/ch4/resources/green.png");
            Image blue = Image.createImage("/ora/ch4/resources/blue.png");
            
            list.append("Red", red);
            list.append("Green", green);
            list.append("Blue", blue);
        } catch (IOException ex) {
            Form form = new Form("Error");
            form.append("Failed to load images");
            return form;
        }
        
        addCommands(list);
        return list;
    }
    
    // Example for Alert
    private Screen createAlertForm() {
        final Form form = new Form("Alert");
        
        // A ChoiceGroup that allows the user to choose between
        // a modal Alert or an Alert with a finite timeout.
        final ChoiceGroup limitGroup = new ChoiceGroup("Timeout", Choice.EXCLUSIVE);
        limitGroup.append("Forever", null);
        limitGroup.append("Bounded 5s", null);
        form.append(limitGroup);
        
        // A Gauge that allows the user to choose the 
        // timeout for the Alert. This appears only if
        // the "Bounded" option is selected.
        final Gauge gauge = new Gauge(null, true, 30, 5);
        
        // A ChoiceGroup that lets the user pick the 
        // type of Alert
        final ChoiceGroup group = createAlertChoiceGroup(true); 
        form.append(group);  
        
        // A Command that is used to display the Alert
        final Command okCommand = new Command("OK", Command.OK, 0);
        
        // Add CommandListener for back/exit commands
        // and the OK command, which is specific to this Form
        form.addCommand(okCommand);
        form.addCommand(exitCommand);
        form.addCommand(backCommand);
        form.setCommandListener(new CommandListener() {
            public void commandAction(Command c, Displayable d) {
                if (c == okCommand) {
                    // Create and display the Alert
                    
                    // Get the alert type from the 
                    // second ChoiceGroup
                    int selectedType = group.getSelectedIndex();
                    AlertType alertType = alertTypes[selectedType];
                    String name = alertTypeNames[selectedType];
                    
                    // Get the timeout. This is FOREVER if the
                    // first item in the first ChoiceGroup is
                    // selected. Otherwise it is the value in
                    // the Gauge
                    int timeout = Alert.FOREVER;
                    String timeoutString = "none";
                    if (limitGroup.isSelected(1)) {
                        // "Bounded" selected - get the timeout.
                        timeout = gauge.getValue() * 1000;
                        timeoutString = gauge.getValue() + "s";                        
                    }
                    
                    // Create the Alert and set the timeout
                    Alert alert = new Alert("Alert!",
                        "Alert type: " + name + "\nTimeout = " + timeoutString,
                        null, alertType);
                    alert.setTimeout(timeout);
                    
                    // Display the Alert.
                    display.setCurrent(alert);                               
                } else {
                    // Delegate others to the usual commandAction
                    ItemMIDlet.this.rumandAction(c, d);
                }                
            }
        });
        
        // Set our own ItemStateListener
        form.setItemStateListener(new ItemStateListener() {
            public void itemStateChanged(Item item) {
                if (item == limitGroup) {
                    if (limitGroup.getSelectedIndex() == 0) {
                        // Get rid of the Gauge
                        form.delete(1);
                    } else {
                        // Add the Gauge
                        form.insert(1, gauge);
                    }
                } else if (item == gauge) {               
                    int value = gauge.getValue();
                    limitGroup.set(1, "Bounded " + value + "s", null);
                }
            }
        });
        return form;
    }
    
        
    // Example for Sounds
    private Screen createSoundsForm() {
        final Form form = new Form("Sounds");
        
        // A ChoiceGroup that lets the user pick the 
        // type of sound
        final ChoiceGroup group = createAlertChoiceGroup(false); 
        form.append(group);  
        addCommands(form);
        
        // Set our own ItemStateListener
        form.setItemStateListener(new ItemStateListener() {
            public void itemStateChanged(Item item) {
                // Get the alert type from the ChoiceGroup
                int selectedType = group.getSelectedIndex();
                AlertType alertType = alertTypes[selectedType];
                boolean result = alertType.playSound(display);
                System.out.println("A sound was " + (result ? "" : "not ")
                                    + "played.");
                
            }
        });
        return form;
    }
    
    // Handles the selection for a Choice 
    private void handleChoiceSelection(Choice choice) {
        int count = choice.size();
        boolean[] states = new boolean[count];
        int selCount = choice.getSelectedFlags(states);
        if (selCount > 0) {
            System.out.println("Selected items:");
            for (int i = 0; i < count; i++) {
                if (states[i]) {
                    System.out.println("\t" + choice.getString(i));
                }
            }
        } else {
            System.out.println("No selected items.");
        }
        int selectedIndex = choice.getSelectedIndex();
        System.out.println("Selected index is " + selectedIndex);        
    }
    
    // Creates a ChoiceGroup containing a set of Alert types
    private ChoiceGroup createAlertChoiceGroup(boolean includeNone) {
        ChoiceGroup group = new ChoiceGroup("Alert Type", Choice.EXCLUSIVE);
        int count = includeNone ? alertTypeNames.length : alertTypeNames.length - 1;
        for (int i = 0; i < count; i++) {
            group.append(alertTypeNames[i], null);
        }
        return group;
    }
}

multiple Choice List

/*--------------------------------------------------
* MultipleChoiceList.java
*
* Create multiple choice list and save selection
* status of each element in an array.
*
* Example from the book:     Core J2ME Technology
* Copyright John W. Muchow   http://www.CoreJ2ME.ru
* You may use/modify for any non-commercial purpose
*-------------------------------------------------*/
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class MultipleChoiceList extends MIDlet implements CommandListener
{
  private Display display;      // Reference to display object 
  private Command cmExit;      // A Command to exit the MIDlet
  private Command cmView;      // View the choice selected
  private List lsPrefs;        // Choice Group of preferences
  public MultipleChoiceList()
  {
    display = Display.getDisplay(this);
    // Create a multiple choice list
    lsPrefs = new List("Preferences", List.MULTIPLE);
    
    // Append options, with no associated images
    lsPrefs.append("Auto Indent", null);
    lsPrefs.append("Replace Tabs", null);
    lsPrefs.append("Wrap Text", null);    
    cmExit = new Command("Exit", Command.EXIT, 1);
    cmView = new Command("View", Command.SCREEN,2);
    // Add commands, listen for events
    lsPrefs.addCommand(cmExit);
    lsPrefs.addCommand(cmView);
    lsPrefs.setCommandListener(this);   
  }
  public void startApp()
  {
    display.setCurrent(lsPrefs);
  }
  public void pauseApp()
  { }
  
  public void destroyApp(boolean unconditional)
  { }
  public void commandAction(Command c, Displayable s)
  {
    if (c == cmView)
    {
      boolean selected[] = new boolean[lsPrefs.size()];
     
      // Fill array indicating whether each element is checked 
      lsPrefs.getSelectedFlags(selected);
      
      for (int i = 0; i < lsPrefs.size(); i++)
        System.out.println(lsPrefs.getString(i) + (selected[i] ? ": selected" : ": not selected"));
    }
    else if (c == cmExit)
    {
      destroyApp(false);
      notifyDestroyed();
    } 
  }
}

Payment MIDlet

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class PaymentMIDlet extends MIDlet {
    private Display display;
    List options = null;
    public PaymentMIDlet() {
       options = new List("Method of Payment", Choice.EXCLUSIVE); 
    }
    public void startApp() {
        display = Display.getDisplay(this);
        options.append("Visa", null);
        options.append("MasterCard", null);
        options.append("Amex", null);
        display.setCurrent(options);
    }
    /**
     * Pause is a no-op since there are no background activities or
     * record stores that need to be closed.
     */
    public void pauseApp() {
    }
    /**
     * Destroy must cleanup everything not handled by the garbage collector.
     * In this case there is nothing to cleanup.
     */
    public void destroyApp(boolean unconditional) {
    }
}

Travel List

import java.io.IOException;
import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.rumand;
import javax.microedition.lcdui.rumandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Image;
import javax.microedition.lcdui.List;
import javax.microedition.midlet.MIDlet;
public class TravelList extends MIDlet implements CommandListener {
  private List mList;
  private Command mExitCommand, mNextCommand;
  public TravelList() {
    String[] stringElements = { "A", "B", "C" };
    Image[] imageElements = { loadImage("/airplane.png"), loadImage("/car.png"),
        loadImage("/hotel.png") };
    mList = new List("Reservation type", List.IMPLICIT, stringElements, imageElements);
    mNextCommand = new Command("Next", Command.SCREEN, 0);
    mExitCommand = new Command("Exit", Command.EXIT, 0);
    mList.addCommand(mNextCommand);
    mList.addCommand(mExitCommand);
    mList.setCommandListener(this);
  }
  public void startApp() {
    Display.getDisplay(this).setCurrent(mList);
  }
  public void commandAction(Command c, Displayable s) {
    if (c == mNextCommand || c == List.SELECT_COMMAND) {
      int index = mList.getSelectedIndex();
      Alert alert = new Alert("Your selection", "You chose " + mList.getString(index) + ".", null,
          AlertType.INFO);
      Display.getDisplay(this).setCurrent(alert, mList);
    } else if (c == mExitCommand)
      notifyDestroyed();
  }
  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }
  private Image loadImage(String name) {
    Image image = null;
    try {
      image = Image.createImage(name);
    } catch (IOException ioe) {
      System.out.println(ioe);
    }
    return image;
  }
}