alarmmidlet.java

j2me的程序

import java.util.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.util.Timer;
import java.util.TimerTask;

public class AlarmMIDlet extends MIDlet
 implements ItemStateListener, CommandListener{
  private Command alarmCommand;
  private Command resetCommand;
  private Command exitCommand;
  
  private Display display;

  private DateField alarmTimeSetting;
  private Form aForm;

  private int dateIndex;
  private Date currentTime;
  private Timer aTimer;
  private alarmTimerTask aTimerTask;
  private boolean dateOK = false;

  public AlarmMIDlet(){
    display = Display.getDisplay(this);
    aForm = new Form("设置闹铃时间");
    currentTime = new Date();
    alarmTimeSetting = new DateField("", DateField.DATE_TIME);
    alarmTimeSetting.setDate(currentTime);

    alarmCommand = new Command("待命中", Command.SCREEN, 1);
    resetCommand = new Command("重置", Command.SCREEN, 1);
    exitCommand = new Command("离开", Command.EXIT, 1);

    dateIndex = aForm.append(alarmTimeSetting);
    aForm.addCommand(alarmCommand);
    aForm.addCommand(resetCommand);
    aForm.addCommand(exitCommand);
    aForm.setCommandListener(this);
    aForm.setItemStateListener(this);
  }

  public void startApp (){
    display.setCurrent(aForm);
  }

  public void pauseApp(){
  }

  public void destroyApp(boolean unconditional){
  }

  public void itemStateChanged(Item item){
    if (item == alarmTimeSetting){
      if (alarmTimeSetting.getDate().getTime() < currentTime.getTime())
        dateOK = false;
      else
        dateOK = true;
    }
  }

  public void commandAction(Command c, Displayable s){
	  if (c == alarmCommand){
	    if (dateOK == false){
	        Alert aAlert = new Alert("无法设置闹铃", "请再做选择", null, null);
            aAlert.setTimeout(Alert.FOREVER);
            aAlert.setType(AlertType.ERROR);
            display.setCurrent(aAlert);
            }
        else{
           aTimer = new Timer();
           alarmTimerTask aTimerTask = new alarmTimerTask();
           long amount = alarmTimeSetting.getDate().getTime() - currentTime.getTime();
           aTimer.schedule(aTimerTask,amount);

           aForm.removeCommand(alarmCommand);
           aForm.removeCommand(resetCommand);
           aForm.delete(dateIndex);

           aForm.setTitle("待命中....");
           }
        }
	  else if(c == resetCommand){
	       alarmTimeSetting.setDate(currentTime = new Date());
	  }
	  else if(c == exitCommand){
         destroyApp(false);
         notifyDestroyed();
	  }
      }

   class alarmTimerTask extends TimerTask{
       public final void run(){
           Alert aAlert = new Alert("时间到 !");
           aAlert.setTimeout(Alert.FOREVER);
           aAlert.setType(AlertType.ALARM);
           AlertType.ERROR.playSound(display);
           display.setCurrent(aAlert);

  	       cancel();
       }
  }
}