commandlistenerdemo.java

来自「Java ME手机应用开发大全一书的配套光盘上的源码」· Java 代码 · 共 60 行

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
public class CommandListenerDemo extends MIDlet implements CommandListener
{
  private Display display; 
  private Alert alert;
  private Form form; 
  private Command exit; 
  private Command submit;
  public CommandListenerDemo()
  {
    display = Display.getDisplay(this);
    exit = new Command("退出", Command.EXIT, 1);
	submit=new Command("提交", Command.SCREEN, 2);
    form = new Form("CommandListener监听器");
    form.addCommand(exit);
	form.addCommand(submit);
    form.setCommandListener(this);
  }
  public void startApp()
  {
   display.setCurrent(form);
  }
  public void pauseApp()
  {
  }
  public void destroyApp(boolean unconditional) 
        throws MIDletStateChangeException
  {
    if (unconditional == false)
    {
     throw new MIDletStateChangeException();
    }
  }      
  public void commandAction(Command command, Displayable displayable)
  {
    if (command == submit)
    {

         alert = new Alert("监听器", "响应Command触发的事件", 
                           null, AlertType.WARNING); 
         alert.setTimeout(Alert.FOREVER); 
         display.setCurrent(alert, form);
     
    }
	 else if(command==exit)
        {
        try
          {
         destroyApp(false);
         notifyDestroyed();
		  }
      catch (MIDletStateChangeException exception)
      {
        
      }
        }
  }
}