Adobe Flex Actionscript Question:

The event flow describes how an event object moves through the display list. The event flow is conceptually divided into three parts.

Capture phase: This phase comprises all of the nodes from the Stage to the parent of the target node

Target phase: This consists solely of the target node.

Bubbling phase: The bubbling phase comprises the nodes encountered on the return trip from the parent of the target node back to the Stage.

The ability to add event listeners along the event flow is useful when a user interface component comprises more than one object. For example, a button object often contains a text object that serves as the button's label. Without the ability to add a listener to the event flow, you would have to add a listener to both the button object and the text object to ensure that you receive notification about click events that occur anywhere on the button. The existence of the event flow, however, allows you to place a single event listener on the button object that handles click events that occur either on the text object or on the areas of the button object that are not obscured by the text object.