User Guide

196 Chapter 6: Components Dictionary
The second usage example uses a dispatcher/listener event model. A component instance
(
comboBoxInstance) dispatches an event (in this case, itemRollOut) and the event is handled by
a function, also called a handler, on a listener object (
listenerObject) that you create. You
define a method with the same name as the event on the listener object; the method is called
when the event is triggered. When the event is triggered, it automatically passes an event object
(
eventObject) to the listener object method. Each event object has properties that contain
information about the event. You can use these properties to write code that handles the event.
For more information, see “EventDispatcher class” on page 415.
Finally, you call the
addEventListener() method on the component instance that broadcasts
the event to register the listener with the instance. When the instance dispatches the event, the
listener is called.
Example
The following example sends a message to the Output panel that indicates the index of the item
that the pointer rolled out of:
form.itemRollOut = function (eventObj) {
trace("Item #" + eventObj.index + " has been rolled out of.");
}
myCombo.addEventListener("itemRollOut", form);
See also
ComboBox.itemRollOver
, EventDispatcher.addEventListener()
ComboBox.itemRollOver
Availability
Flash Player 6 (6.0 79.0).
Edition
Flash MX 2004.
Usage
Usage 1:
on(itemRollOver){
// your code here
}
Usage 2:
listenerObject = new Object();
listenerObject.itemRollOver = function(eventObject){
// your code here
}
comboBoxInstance.addEventListener("itemRollOver", listenerObject)
Event object
In addition to the standard properties of the event object, the itemRollOver event has an index
property. The index is the number of the item that the pointer rolled over.