Mega Code Archive
Date Field
<![CDATA[
/*--------------------------------------------------
* Snooze.java
*
* Example from the book: Core J2ME Technology
* Copyright John W. Muchow http://www.CoreJ2ME.com
* You may use/modify for any non-commercial purpose
*-------------------------------------------------*/
import java.util.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import java.util.Timer;
import java.util.TimerTask;
public class Snooze extends MIDlet implements ItemStateListener, CommandListener
{
private Display display; // Reference to display object
private Form fmMain; // The main form
private Command cmSnooze; // Start the timer
private Command cmReset; // Reset to current date/time
private Command cmExit; // Exit the MIDlet
private DateField dfSnoozeTime; // How long to snooze
private int dateIndex; // Index of the DateField on the Form
private Date currentTime; // Current time...changes when pressing reset
private Timer tmSnooze; // The timer - keeps track of system time
private SnoozeTimer ttSnooze; // Called by the timer
private boolean dateOK = false; // Was the user input valid?
public Snooze()
{
display = Display.getDisplay(this);
// The main form
fmMain = new Form("When to sound the alarm:");
// Save today's date
currentTime = new Date();
// DateField with todays date as a default
dfSnoozeTime = new DateField("", DateField.DATE_TIME);
dfSnoozeTime.setDate(currentTime);
// All the commands/buttons
cmSnooze = new Command("Snooze", Command.SCREEN, 1);
cmReset = new Command("Reset", Command.SCREEN, 1);
cmExit = new Command("Exit", Command.EXIT, 1);
// Add to form and listen for events
dateIndex = fmMain.append(dfSnoozeTime);
fmMain.addCommand(cmSnooze);
fmMain.addCommand(cmReset);
fmMain.addCommand(cmExit);
fmMain.setCommandListener(this);
fmMain.setItemStateListener(this);
}
public void startApp ()
{
display.setCurrent(fmMain);
}
public void pauseApp()
{ }
public void destroyApp(boolean unconditional)
{ }
public void itemStateChanged(Item item)
{
if (item == dfSnoozeTime)
{
// If the user selected date and/or time that is earlier
// than today, set a flag. We are using getTime()
// method of the Date class, which returns the # of
// milliseconds since January 1, 1970
if (dfSnoozeTime.getDate().getTime() < currentTime.getTime())
dateOK = false;
else
dateOK = true;
}
}
public void commandAction(Command c, Displayable s)
{
if (c == cmSnooze)
{
if (dateOK == false)
{
Alert al = new Alert("Unable to set alarm", "Please choose another date and time.", null, null);
al.setTimeout(Alert.FOREVER);
al.setType(AlertType.ERROR);
display.setCurrent(al);
}
else
{
// Create a new timer
tmSnooze = new Timer();
ttSnooze = new SnoozeTimer();
// Amount of time to delay
long amount = dfSnoozeTime.getDate().getTime() - currentTime.getTime();
tmSnooze.schedule(ttSnooze,amount);
// Remove the commands
fmMain.removeCommand(cmSnooze);
fmMain.removeCommand(cmReset);
// Remove the DateField
fmMain.delete(dateIndex);
// Change the Form message
fmMain.setTitle("Snoozing...");
}
}
else if (c == cmReset)
{
// Reset to the current date/time
dfSnoozeTime.setDate(currentTime = new Date());
}
else if (c == cmExit)
{
destroyApp(false);
notifyDestroyed();
}
}
// Handle the timer task
private class SnoozeTimer extends TimerTask
{
public final void run()
{
Alert al = new Alert("Time to wake up!");
al.setTimeout(Alert.FOREVER);
al.setType(AlertType.ALARM);
AlertType.ERROR.playSound(display);
display.setCurrent(al);
// Cancel this timer task
cancel();
}
}
}
]]>