MACROMEDIA FLASH MX 2004-ACTIONSCRIPT LANGUAGE, Reference

Page: 494 / 1104

494 Chapter 2: ActionScript Language Reference
MovieClip._alpha
Availability
Flash Player 4.
Usage
my_mc ._alpha :Number
Description
Property; the alpha transparency value of the movie clip specified by
my_mc
. Valid values are 0
(fully transparent) to 100 (fully opaque). The default value is 100. Objects in a movie clip with
_alpha
set to 0 are active, even though they are invisible. For example, you can still click a button
in a movie clip whose
_alpha
property is set to 0. To disable the button completely, you can set
the movie clip's
_visible
property to false.
You can extend the methods and event handlers of the MovieClip class by creating a subclass. For
more information, see “Assigning a class to a movie clip symbol” in
Using ActionScript in Flash .
Example
The following code sets the
_alpha
property of a dynamically created movie clip named
holder_mc
to 50% when the mouse rolls over the movie clip. Add the following ActionScript to
your FLA or AS file:
this.createEmptyMovieClip("holder_mc", this.getNextHighestDepth());
holder_mc.createEmptyMovieClip("image_mc", holder_mc.getNextHighestDepth());
// replace with your own image or use the following
holder_mc.image_mc.loadMovie("http://www.macromedia.com/devnet/mx/blueprint/
articles/nielsen/spotlight_jnielsen.jpg");
holder_mc.onRollOver = function() {
this._alpha = 50;
};
holder_mc.onRollOut = function() {
this._alpha = 100;
};
See also
Button._alpha , TextField._alpha , MovieClip._visible