[Antares]

Раз ты используешь 1.5, у тебя в руках полная документация. Скажу честно, она написана лучше, чем любая другая дока у Макромедии.

Сообщение от Flex ActionScript and MXML API Reference

Application.initialize

Broadcast when the component has finished its construction and has all initialization properties set. Most components create all or most of their children during construction. All properties specified in the initObj parameter to createClassObject, createObject, or View.createChild, and all MXML attributes have been set on the component, but may not be fully processed. This is because after the initialization phase, the component gets a chance to process all of the properties or attributes at once instead of having to process them individually. Thus, even though a property like hScrollPolicy is set to "on", the component may not have actually created the scrollbar yet. After the initialization phase, properties are processed, the component is measured, layed out and drawn, after which the createComplete event is broadcast. The event object's target property contains a reference to the component that triggered the event. The event object's type property contains the name of the event, initialize.