// This example is Multiple choice check boxes

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class MultipleChoice extends MIDlet implements ItemStateListener, CommandListener{
  private Display display; // a display
  private Form fmMain; // main form
  private Command cmExit; // exit command
  private Command cmView; // view command to view the slected items
  private int selectIndex; // Index of the select all option
  private ChoiceGroup cgPrefer; // choice group of prefernces
  private int choiceGroupIndex; // index of the choice group

  // contructor
  public MultipleChoice(){
    display = Display.getDisplay(this); // get diplay

    // Create a multiple choice group
    cgPrefer = new ChoiceGroup("Preferences", Choice.MULTIPLE);

    // Append options without any images

    cgPrefer.append("Auto Indent", null);// append an Auto Indent option
    cgPrefer.append("Replace Tab", null); // append a Replace Tab option
    cgPrefer.append("Wrap Text", null); //append Wrap Text option
    selectIndex = cgPrefer.append("Select All", null); // append Select All option

    // set Auto indent as default choice
    cgPrefer.setSelectedIndex(selectIndex, true);

    // create commands
    cmExit = new Command("Exit", Command.EXIT, 1);
    cmView = new Command("View", Command.SCREEN, 2);

    // create Form, add commands and listen for events
    fmMain = new Form(" "); // a form with no title
    choiceGroupIndex = fmMain.append(cgPrefer);

    fmMain.addCommand(cmExit);
    fmMain.addCommand(cmView);
    fmMain.setCommandListener(this);
    fmMain.setItemStateListener(this);
  }

  // start App
  public void startApp(){
    display.setCurrent(fmMain);
  }

  // pause App
  public void pauseApp(){

  }

  // destroy App
  public void destroyApp(boolean unconditional){

  }
  public void commandAction(Command c, Displayable s){
    if(c == cmView){
      boolean selected[] = new boolean[cgPrefer.size()];

      // examine and see whether any option is selected
      cgPrefer.getSelectedFlags(selected);

      for (int i = 0; i<cgPrefer.size(); i++)
        System.out.println(cgPrefer.getString(i) + (selected[i] ? ": selected"
            : ":not selected"));
    }
            else if(c == cmExit){
              destroyApp(false);
              notifyDestroyed();
            }
  }

  // itemStateChanged method  due to ItemStateListener
  public void itemStateChanged(Item item){
    if(item == cgPrefer){
      // is select all option ticked?
      if(cgPrefer.isSelected(selectIndex)){
        // set all check boxes to true
        for (int i = 0; i<cgPrefer.size() -1; i++)
          cgPrefer.setSelectedIndex(i, true);

          // remove check by select all
          cgPrefer.setSelectedIndex(selectIndex, false);
      }
    }

  }
}