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.

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Chapter 16: ActionScript Authoring Environment

We must also ensure that no code attempts to access portions of a movie that have

not yet loaded. To check whether a specific portion of a movie has loaded, use either

the movie clip

_framesloaded property or the getBytesLoaded() method. For sample

code, see the entry for

Movieclip._framesloaded in the Language Reference.

Adding Scripts to Buttons

In Flash 5, button code is attached directly to button objects on stage. For example,

in Flash 5, if we want the clicking of a button to advance the playhead of a movie to

a frame labeled

section1, we attach the following code to that button:

on (release) {

gotoAndStop("section1");

}

In most cases, Flash MX’s button callback-function-based event handlers should be

used on a movie clip timeline in place of the older style on(event) syntax. However, in

some trivial situations it is more convenient to add code directly to a button.

To add code to a button, select the button on the Stage, and add the code to the

Script pane of the Actions panel. Code on buttons must always be placed in an event

handler that identifies the circumstances under which the code should execute. For

example, the event that triggers most button actions is release. We might also use the

rollOver event, causing code to execute ...