ActionScript for Flash MX: The Definitive Guide, Second Edition

This is the Title of the Book, eMatter Edition

Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.

Flash 5–style onClipEvent( ) Order of Execution

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Moral of the story: obviously, the location of the function declaration

can change, so it’s a little dangerous to use unqualified references

inside handlers at all. Qualify all nonlocal identifiers within handlers

with

this or some other explicit object reference.

Values of the this Keyword

In our study of ActionScript’s event handling tools, we’ve encountered the this key-

word several times. Within an event handler,

this normally refers to the object that

received notification of the event. However, Flash’s evolution through multiple event

systems has complicated the issue. Table 10-2 provides a guide to the values of the

this keyword in ActionScript’s various event handling mechanisms.

Flash 5–style onClipEvent( )

Order of Execution

Some movies have code dispersed across multiple timelines and on( ) and

onClipEvent( ) handlers. It’s not uncommon, therefore, for a single frame to require

the execution of many separate blocks of code—some in event handlers, some on

frames in clip timelines, and some on the main timelines of documents in the Player.

In these situations, the order in which the various bits of code execute can become

quite complex and can greatly affect a program’s behavior. We can prevent surprises

and guarantee that our ...