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 10: Events and Event Handling

clip._x += x;

clip._ y += y;

}

// CODE ON CLIP

// Call the main timeline function and tell it to move the

// current clip by passing a reference with the this keyword

onClipEvent (enterFrame) {

_root.move(this, 10, 15);

}

In Flash Player 5.0.30.0, a bug prevents gotoAndStop() and

gotoAndPlay() from working inside a clip handler when used with

string literal labels. Such commands are simply ignored. For example,

this does not work:

onClipEvent (load) {

gotoAndStop("intro"); // Won't work in Flash 5.0.30.0

}

To work around the bug, use a self-reflexive clip reference (i.e., this),

as in:

onClipEvent(load) {

this.gotoAndStop("intro");

}

Remember that statements in onClipEvent( ) handlers are scoped to

the clip’s timeline, not to the handler function’s local scope or the

clip’s parent timeline (the timeline upon which the clip resides).

For example, suppose we place our ball clip on the main timeline of a movie, and

the main timeline (not

ball’s timeline) has a moveBall( ) function defined on it. We

may absent-mindedly call moveBall( ) from an event handler on

ball, like this:

onClipEvent (enterFrame) {

moveBall( ); // Does nothing! There's no moveBall() function in ball.

// The moveBall() function is defined on _root.

}

We must refer to the moveBall( ) function ...