MACROMEDIA FLASH MX 2004-ACTIONSCRIPT LANGUAGE, Reference

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Object.registerClass() 667
Object.registerClass()
Availability
Flash Player 6. If you are using ActionScript 2.0 classes, you can use the ActionScript 2.0 Class
field in the Linkage Properties or Symbol Properties dialog box to associate an object with a class
instead of using this method. For more information, see “Assigning a class to a movie clip
symbol”. in
Using ActionScript in Flash .
Usage
Object.registerClass( symbolID:String , theClass:Function ) : Boolean
Parameters
symbolID
String; the linkage identifier of the movie clip symbol or the string identifier for the
ActionScript class.
theClass
A reference to the constructor function of the ActionScript class or
null
to
unregister the symbol.
Returns
A Boolean value: if the class registration succeeds, a value of
true
is returned;
false
otherwise.
Description
Method; associates a movie clip symbol with an ActionScript object class. If a symbol doesn’t
exist, Flash creates an association between a string identifier and an object class.
When an instance of the specified movie clip symbol is placed on the Timeline, it is registered to
the class specified by the
theClass
parameter rather than to the class MovieClip.
When an instance of the specified movie clip symbol is created by using MovieClip.attachMovie()
or MovieClip.duplicateMovieClip() , it is registered to the class specified by
theClass
rather than
to the MovieClip class. If
theClass
is
null
, this method removes any ActionScript class
definition associated with the specified movie clip symbol or class identifier. For movie clip
symbols, any existing instances of the movie clip remain unchanged, but new instances of the
symbol are associated with the default class MovieClip.
If a symbol is already registered to a class, this method replaces it with the new registration.
When a movie clip instance is placed by the Timeline or created using
attachMovie()
or
duplicateMovieClip()
, ActionScript invokes the constructor for the appropriate class with the
keyword
this
pointing to the object. The constructor function is invoked with no parameters.
If you use this method to register a movie clip with an ActionScript class other than MovieClip,
the movie clip symbol doesn’t inherit the methods, properties, and events of the built-in
MovieClip class unless you include the MovieClip class in the prototype chain of the new class.
The following code creates a new ActionScript class called
theClass
that inherits the properties
of the MovieClip class:
theClass.prototype = new MovieClip();
See also
MovieClip.attachMovie() , MovieClip.duplicateMovieClip()