/*
* @(#)ItemStateListener.java 1.13 02/07/24 @(#)
*
* Copyright (c) 1999-2002 Sun Microsystems, Inc. All rights reserved.
* PROPRIETARY/CONFIDENTIAL
* Use is subject to license terms.
*/
package javax.microedition.lcdui;
/**
* This interface is used by applications which need to receive
* events that indicate changes in the internal
* state of the interactive items within a {@link Form Form}
* screen.
*
* @see Form#setItemStateListener(ItemStateListener)
* @since MIDP 1.0
*/
public interface ItemStateListener {
/**
* Called when internal state of an <code>Item</code> has been
* changed by the user.
* This happens when the user:
* <UL>
* <LI>changes the set of selected values in a
* <code>ChoiceGroup</code>;</LI>
* <LI>adjusts the value of an interactive <code>Gauge</code>;</LI>
* <LI>enters or modifies the value in a <code>TextField</code>;</LI>
* <LI>enters a new date or time in a <code>DateField</code>; and</LI>
* <LI>{@link Item#notifyStateChanged} was called on an
* <code>Item</code>.</LI>
* </UL>
*
* <p> It is up to the device to decide when it considers a
* new value to have been entered into an <code>Item</code>. For example,
* implementations of text editing within a <code>TextField</code>
* vary greatly
* from device to device. </P>
*
* <p>In general, it is not expected that the listener will be called
* after every change is made. However, if an item's value
* has been changed, the listener
* will be called to notify the application of the change
* before it is called for a change on another item, and before a
* command is delivered to the <code>Form's</code>
* <code>CommandListener</code>. For implementations that have the
* concept of an input
* focus, the listener should be called no later than when the focus moves
* away from an item whose state has been changed. The listener
* should be called only if the item's value has actually been
* changed.</P>
*
* <p> The listener is not called if the application changes
* the value of an interactive item. </p>
*
* @param item the item that was changed
*/
public void itemStateChanged(Item item);
}
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