Java Tutorial/J2ME/List

Implicit Menu

   <source lang="java">

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 J2MEListImplicit extends MIDlet implements CommandListener {

 private Display display;
 private List list;
 private Command exit;
 Alert alert;
 public J2MEListImplicit() {
   display = Display.getDisplay(this);
   exit = new Command("Exit", Command.EXIT, 1);
   list = new List("Menu:", List.IMPLICIT);
   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();
   }
 }

}</source>

List check box

   <source lang="java">

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 J2MEListCheckBox extends MIDlet implements CommandListener {

 private Display display;
 private Command exit;
 private Command submit;
 private List list;
 public J2MEListCheckBox() {
   display = Display.getDisplay(this);
   list = new List("Select Media", List.MULTIPLE);
   list.append("Books", null);
   list.append("Movies", null);
   list.append("Television", null);
   list.append("Radio", null);
   exit = new Command("Exit", Command.EXIT, 1);
   submit = new Command("Submit", Command.SCREEN, 2);
   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 x = 0; x < choice.length; x++) {
       if (choice[x]) {
         message.append(list.getString(x));
         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();
   }
 }

}</source>

List radio button

   <source lang="java">

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 J2MEListRadioButtons extends MIDlet implements CommandListener {

 private Display display;
 private Command exit;
 private Command submit;
 private List list;
 public J2MEListRadioButtons() {
   display = Display.getDisplay(this);
   list = new List("Select one", List.EXCLUSIVE);
   list.append("Male", null);
   list.append("Female", null);
   exit = new Command("Exit", Command.EXIT, 1);
   submit = new Command("Submit", Command.SCREEN, 2);
   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) {
     Alert alert = new Alert("Choice", list.getString(list.getSelectedIndex()), null, null);
     alert.setTimeout(Alert.FOREVER);
     alert.setType(AlertType.INFO);
     display.setCurrent(alert);
     list.removeCommand(submit);
   } else if (command == exit) {
     destroyApp(false);
     notifyDestroyed();
   }
 }

}</source>

List with strings and images

   <source lang="java">

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.lcdui.TextBox; import javax.microedition.lcdui.TextField; import javax.microedition.midlet.MIDlet; public class ListMIDlet extends MIDlet implements CommandListener {

 TextBox main;
 private Command exitCommand;
 private Command exclusiveCommand;
 private Command multipleCommand;
 private Command implicitCommand;
 private Command confirmCommand;
 private List aEXCLUSIVEList;
 private List aMULTIPLEList;
 private List aIMPLICITList;
 String[] position = { "1", "2", "3" };
 String[] hobby = { "A", "B", "C", "D", "E" };
 Image[] positionIcon = { createImage("/1.png"), createImage("/2.png"), createImage("/3.png") };
 Image[] hobbyIcon = { createImage("/A.png"), createImage("/B.png"), createImage("/C.png"),
     createImage("/D.png"), createImage("/E.png") };
 private Display display;
 private String currentScreen = "";
 public ListMIDlet() {
   display = Display.getDisplay(this);
   exitCommand = new Command("exit", Command.SCREEN, 1);
   exclusiveCommand = new Command("exclusive", Command.SCREEN, 1);
   multipleCommand = new Command("multiple", Command.SCREEN, 1);
   implicitCommand = new Command("implicit", Command.SCREEN, 1);
   confirmCommand = new Command("confirm", Command.SCREEN, 2);
 }
 public void startApp() {
   main = new TextBox("main", null, 256, TextField.ANY);
   main.addCommand(exitCommand);
   main.addCommand(exclusiveCommand);
   main.addCommand(multipleCommand);
   main.addCommand(implicitCommand);
   main.setCommandListener(this);
   display.setCurrent(main);
   currentScreen = "Main";
 }
 public void pauseApp() {
 }
 public void destroyApp(boolean unconditional) {
 }
 private Image createImage(String name) {
   Image aImage = null;
   try {
     aImage = Image.createImage(name);
   } catch (IOException e) {
   }
   return aImage;
 }
 private void exclusiveList() {
   aEXCLUSIVEList = new List("exclusive", List.EXCLUSIVE, position, positionIcon);
   aEXCLUSIVEList.addCommand(exitCommand);
   aEXCLUSIVEList.addCommand(confirmCommand);
   aEXCLUSIVEList.setCommandListener(this);
   display.setCurrent(aEXCLUSIVEList);
   currentScreen = "exclusive";
 }
 private void multipleList() {
   aMULTIPLEList = new List("multiple", List.MULTIPLE, hobby, hobbyIcon);
   aMULTIPLEList.addCommand(exitCommand);
   aMULTIPLEList.addCommand(confirmCommand);
   aMULTIPLEList.setCommandListener(this);
   display.setCurrent(aMULTIPLEList);
   currentScreen = "multiple";
 }
 private void implicitList() {
   aIMPLICITList = new List("implicit", List.IMPLICIT);
   aIMPLICITList.append("A", createImage("/A.png"));
   aIMPLICITList.append("B", createImage("/B.png"));
   aIMPLICITList.append("C", createImage("/C.png"));
   aIMPLICITList.append("D", createImage("/D.png"));
   aIMPLICITList.append("E", createImage("/E.png"));
   aIMPLICITList.addCommand(exitCommand);
   aIMPLICITList.setCommandListener(this);
   display.setCurrent(aIMPLICITList);
   currentScreen = "implicit";
 }
 public void commandAction(Command c, Displayable s) {
   if (c == exitCommand) {
     if (currentScreen == "implicit") {
       destroyApp(false);
       notifyDestroyed();
     } else {
       display.setCurrent(main);
       currentScreen = "no";
     }
   }
   if (c == exclusiveCommand) {
     exclusiveList();
   }
   if (c == multipleCommand) {
     multipleList();
   }
   if (c == implicitCommand) {
     implicitList();
   }
   if (c == confirmCommand) {
     Alert aAlert;
     if (currentScreen == "implicit") {
       int aIndex = aEXCLUSIVEList.getSelectedIndex();
       aAlert = new Alert("Result", position[aIndex], null, AlertType.INFO);
       display.setCurrent(aAlert);
     }
     if (currentScreen == "multiple") {
       String result = "result\n";
       for (int i = 0; i < aMULTIPLEList.size(); i++)
         if (aMULTIPLEList.isSelected(i))
           result += hobby[i] + ", ";
       aAlert = new Alert("alert", result, null, AlertType.INFO);
       aAlert.setTimeout(5000);
       display.setCurrent(aAlert);
     }
   }
   if (c == List.SELECT_COMMAND) {
     int aIndex = aIMPLICITList.getSelectedIndex();
     String menuItem = aIMPLICITList.getString(aIndex);
     Alert aAlert = new Alert("imple", menuItem, null, AlertType.INFO);
     aAlert.setTimeout(5000);
     display.setCurrent(aAlert);
   }
 }

}</source>

Use List

   <source lang="java">

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 J2METravelList extends MIDlet implements CommandListener {

 private List mList;
 private Command mExitCommand, mNextCommand;
 public J2METravelList() {
   String[] stringElements = { "A", "C", "H" };
   Image[] imageElements = { loadImage("/a.png"), loadImage("/c.png"),
       loadImage("/h.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;
 }

}</source>

Use List option to hold choice

   <source lang="java">

import javax.microedition.lcdui.Choice; import javax.microedition.lcdui.Display; import javax.microedition.lcdui.List; import javax.microedition.midlet.MIDlet; public class PaymentMIDlet extends MIDlet {

 private Display display;
 List 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);
 }
 public void pauseApp() {
 }
 public void destroyApp(boolean unconditional) {
 }

}</source>