J2ME Item State Listener Example

In this application we are going to shows how to implement the
ItemStateListener interface in the j2me midlet. The ItemStateListener interface
is used by applications which need to receive events that indicate changes in
the internal state of the interactive items within a Form screen.
The ItemStateListener interface having only one method that is:
itemStateChanged(Item item):- This is the void type method which
called when internal state of an Item has been changed by the user.
By this example you can learn the implementation of ItemStateListener in only
three easy steps:
- In the first step we create the DateField and set the current date with
this field as shown in figure.

2. In the second step click on select button then the calendar will be
display as shown below.

3. And finally choose the new date and click on "Save" then
the new date will display on the mobile window as shown.

ItemStateListenerMIDlet.java
import java.util.*;
import javax.microedition.lcdui.*;
import javax.microedition.midlet.*;
public class ItemStateListenerMIDlet extends MIDlet{
private Display display;
private Form form;
private Date date = new Date();
private Calendar calendar;
private DateField today;
public ItemStateListenerMIDlet(){
display = Display.getDisplay(this);
}
public void startApp(){
form = new Form("ItemStateListener");
ItemStateListener listener = new ItemStateListener(){
Calendar calendar = Calendar.getInstance(TimeZone.getDefault());
public void itemStateChanged(Item item){
calendar.setTime(((DateField)item).getDate());
}
};
form.setItemStateListener(listener);
today = new DateField("Today's Date:", DateField.DATE);
today.setDate(date);
form.append(today);
display.setCurrent(form);
}
public void pauseApp(){
display = null;
}
public void destroyApp(boolean unconditional){
notifyDestroyed();
}
}
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