This example shows how to create a List which contains CheckBox elements.




 /*
J2ME: The Complete Reference

James Keogh

Publisher: McGraw-Hill

ISBN 0072227109

*/
//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.midlet.*;
import javax.microedition.lcdui.*;
public class ListCheckBox extends MIDlet implements CommandListener
{
  private Display display; 
  private Command exit; 
  private Command submit; 
  private List list; 
  public ListCheckBox()
  {
    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();
    }
  }
}

 

 

 

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