Equivalent of describeType for Flex Component EVENTS
Using "introspection" In Flex I can say:
var classInfo:XML=describeType(SomeObject);
Which will list for me the Accessors, Methods And Variables. (http://livedocs.adobe.com/flex/3/html/help.html?content=usingas_8.html)
But what is the equivalent to programmatically inspect all of an object's possible EVENTS?
(NOT JUST the events for which event listeners have been set, but to somehow step through a list of all VALID EVENTS for which event listeners may POTENTIALLY be set -- I realize that such lists are re开发者_如何学Goadily available online, and that's great for cases when I know the object's type at design type, but I require some way to inspect any given displayobject programmatically at runtime, and determine what events, if any, are or may be associated with it.)
There isn't a way.
The Event information defined using the event metadata tag is done only for the purposes of code hinting and documentation via ASDocs. It has no relevance to events that the component may or may not be firing.
At any point in time, a portion of code can call "dispatchEvent" and dispatch that event. This is used very commonly for "somePropertyChanged" events which are used for bindings. These events rarely, if ever, get documented using the event metadata. But, the component still fires them.
Bubbling confuses the issue; because if a component's child fires an event where the bubble property is true; then it is almost the same as that component firing the event. How, programmatically, would you figure that out without some sort of code analyzer?
That said, there is a compiler argument to retain metadata ( keep-as3-metadata at http://livedocs.adobe.com/flex/3/html/help.html?content=compilers_14.html and http://jacwright.com/blog/72/using-your-own-custom-metadata-in-as3/ ).
I believe if you do that, then there is a way to get the event metadata from the component; I thought using describeType. But, remember that metadata is not the whole story in terms of events.
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