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
- {@link Item#notifyStateChanged} 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.
