How to declare valid strings for the type argument in e.g. foo(type:String)

[Pelle]

Hi!

I noticed that some as3 class methods that uses an argument like 'type:String' also has declared the set of valid strings(constants). How is that done and can I do it or is that only for the adobe guys?

I attached a little picture to show what I mean.

When I implement the call to URLLoader.addEventListener(type:String, ...) flex somehow knows what string constants are valid and gives me a selection

[panel]

It is class with static variables.

package
{
    public class Direction
    {
        public static const NEXT:String = "Next";
        public static const PREV:String = "Prev";
    }
}

usage:

myMoveFunction(Direction.NEXT)

[Pelle]

Hi!

Thanx for the reply... but thats not it I'm afraid.

If you look at the Event class it declares a lot of constants but the URLLoader.addEventlistener(type:String, ...) method actually somewhere declares which one of those are valid input.

Have a look in the as3 documentation for the URLLoader class. Scroll down to the table called "Events" (thats the third one). As you can see, those are a subset of a lot of static constants declared in a lot of different classes and among the the Event class.

Whats also interesting is that two of the "valid events" is inherited. Wats also interesting is that the "valid events" is not connected to the method addEventListener(...) since that one also is inherited. It seems to be some sort of declaration on its own... And I want to know how to do that NOW!

As you can see from the attached image, The super class of URLLoader, EventDispatcher has only declared two events.

[panel]

I doubt it's possible. I am guessing it's implemented someware in Flex autocompilation system.

[Pelle]

Nope!

That stuff must have been declared somewhere in those classes. The documentation clearly shows that there is inheritence support. If they could declare it, so could I. Nothing is impossible...

/Pelle

[panel]

Originally Posted by Pelle

Nope!
That stuff must have been declared somewhere in those classes. The documentation clearly shows that there is inheritence support. If they could declare it, so could I.
/Pelle

Even if you are right those are core classes (written in C++ propably), so it's only for the adobe guys

Originally Posted by Pelle

Nope!
Nothing is impossible...

... but somteimes you have spent to mutch time do do something.

[senocular]

I'm pretty sure those code hints are stored probably in some XML file somewhere in the Flex installation

[Pelle]

Ok...

Would have been neat though...

[icktoofay]

If they are XML files though, you can write your own also.

[senocular]

You should be able to. I don't know enough about Flex to know how or where they are stored, but I know its XML in Flash and given that Flex is built on Eclipse, I can only imagine something similar is used (then again, its quite possible that they are defined in some Java class but I think that would be dumb). I think there is also some dynamic code hinting going on based on recognized definitions but I don't know how they play together with predefined (the EventDispatcher list seems weird to me)