List with strings and images : List « J2ME « Java Tutorial

1. Java Tutorial
2. J2ME
3. List

import java.io.IOException;

import javax.microedition.lcdui.Alert;
import javax.microedition.lcdui.AlertType;
import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
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);
    }
  }

}

31.11.List
	31.11.1.	Use List
	31.11.2.	Use List option to hold choice
	31.11.3.	List with strings and images
	31.11.4.	Implicit Menu
	31.11.5.	List check box
	31.11.6.	List radio button