Comments on: ClassFinder class

By: Crear Dinámicamente Instancias de Clase en AS3 | ¿y por qué no?

Crear Dinámicamente Instancias de Clase en AS3 | ¿y por qué no? — Sat, 13 Jun 2009 00:15:00 +0000

[...] Nota: En AS2, se puede hacer lo mismo así: [...]

By: Actionscript Classes » ClassFinder

Actionscript Classes » ClassFinder — Sat, 16 Dec 2006 05:14:44 +0000

[...] http://dynamicflash.com/2005/03/class-finder/ [...]

By: Troy

Troy — Sun, 12 Nov 2006 19:35:00 +0000

Great find.

Inspired by Spring (http://www.springframework.org/) in Java development, I implemented an similar (using eval()) because it was easy, so the implementation is xml configrable, allowing debugging versions of the code, dropped in without recompiling.

One plus about your approach is eval() is not supported in Flash9, so your method is probably better.

I use the static reference links to setup a code library that is created by MTASC and pulled in via a skin file on the fly.

By: Dave

Dave — Wed, 29 Mar 2006 12:37:05 +0000

"Though eval() would indeed work ... it just feels a little dirty"

I know what you mean, but why make work for yourself? As long as code strikes a good balance between readability and efficiency it shoud be a go-er...

Great site by the way.

By: Steve

Steve — Mon, 14 Mar 2005 13:18:53 +0000

Bob: Absolutely! In fact, we’re going to be doing just that for our application just as soon as we ship the new version. Now if only I could find an efficient (both byte- and processor-wise) component set with a DataGrid replacement, I’d be laughing.

By: Bob

Bob — Mon, 14 Mar 2005 10:58:55 +0000

Right. If file size would be an issue you could perhaps load the dependancy classes in the main swf through a seperate swf, specified by the XML.

That would allow for dynamic updating of the main swf, and a smaller file size as well .

By: Steve

Steve — Fri, 11 Mar 2005 13:57:21 +0000

@Bob: I’m not too worried about file size here as the classes I’m choosing between are very lightweight. The reason I need runtime instantiation is that I don’t know which of my classes I need to instantiate until I load the class name from the configuration XML file.

@Simon: Though eval() would indeed work, I try to avoid using it wherever possible. I can’t really explain why, it just feels a little dirty Having said that (and without checking )I guess using eval() would make ClassFinder more efficient, but unless you’re instantiating thousands of objects this way it wouldn’t really be noticable.

By: Simon Wacker

Simon Wacker — Fri, 11 Mar 2005 12:45:47 +0000

Why aren’t you just using eval? var myClass:Function = Function(eval(”fullyQualifiedClassName”)); I mean, you do not do any extra checking whether a class with the given name does even exist and that like. You are also not checking whether the passed-in class name is null or undefined. The as2lib does also offer that functionality together with a lot more. Take a look at the Reflection API (org.as2lib.env.reflect). Note that the current version is rather heavy weight. We are going to release an improved and lighter reflection api (together with as2lib 0.1 final) in about 1 month.

By: Bob Donderwinkel

Bob Donderwinkel — Fri, 11 Mar 2005 12:26:45 +0000

Using dependancy links to classes also increases the swf filesize for each class included. So what’s your aim exactly with runtime instantiating the classes with xml, unless you know already which classes you are going to use?

It would mean you have to include each class as a dependancy in the swf manually in any case, negating the runtime instantiating benefit perhaps. And if you would use a basic class making dependancy links to all classes you could possibly need, the filesize could get bigger then needed since you perhaps wont use all the classes.

Nice work though. I’m guessing your ClassFinder is more streamlined then mx.utils.ClassFinder .

By: Steve

Steve — Fri, 11 Mar 2005 09:36:52 +0000

Thanks Richard. I’ll have a look at this later.