ItemStateListener.java

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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 Form screen.
 * Since: MIDP 1.0 See Also:Form.setItemStateListener(ItemStateListener)
 */
public interface ItemStateListener{
    /**
     * Called when internal state of an Item has been changed by the user. This happens when the user: changes the set of selected values in a ChoiceGroup; adjusts the value of an interactive Gauge; enters or modifies the value in a TextField; enters a new date or time in a DateField; and
     * was called on an Item.
     * It is up to the device to decide when it considers a new value to have been entered into an Item. For example, implementations of text editing within a TextField vary greatly from device to device.
     * 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 Form's CommandListener. 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.
     * The listener is not called if the application changes the value of an interactive item.
     */
    public abstract void itemStateChanged(Item item);

}