ADF 11g Rich Client Components have a facility called the Change(d) Indicator. The changed attribute is specified using a Boolean value or expression (typically the latter). When the expression evaluates to true, a visual indication is rendered on the component that signifies to the user that the item’s value has changed. While we can use this indicator in any way we see fit, a logical use case would be to highlight with this indicator any field that has been updated as a result of a partial page request/refresh – the AJAX style immediate update of portion of the page as a response to action by the user.

For example: when the temperature is entered in the Temperature Fahrenheit item (or changed using the Spin Controls), an auto submit is performed that in turn leads to an update of the Temperature Celsius item. Because of the changed attribute, the user can clearly identify the items that were automagically changed. Note: In this case we have used a custom skin that specifies another icon for the changed indicator (you will see the default icon later on in this article).

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