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.

Referring to Instances and Main Movies

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In order to refer to an instance directly (as shown in the preceding trace() example),

the instance must reside on the timeline to which our code is attached. For example,

if we have an instance named

clouds_mc placed on the main timeline of a document,

we can refer to

clouds_mc from code attached to the main timeline, as follows:

// Set a property of the instance

clouds_mc._alpha = 60;

// Invoke a method on the instance

clouds_mc.play();

// Place the instance in an array of other related instances

var background = [clouds_mc, sky_mc, mountains_mc];

If the instance we want to reference does not reside on the same timeline as our code,

we must use a more elaborate syntax, as described later in this section under “Refer-

ring to Nested Instances.”

Referring to the Current Instance or Movie

We don’t always have to use an instance’s name when referring to a clip. Code

attached to a frame in an instance’s timeline can refer to that instance’s properties

and methods directly, without any instance name.

For example, to set the

_alpha property of a clip named cloud_mc, we can place the

following code on a frame in the

cloud_mc timeline:

_alpha = 60;

Similarly, to invoke the play() method on cloud_mc from a frame in the cloud_mc

timeline, we can simply use:

play( ...