Wow... Thanks! Ben, would you please explain the last part that talks about type casting? Another Question: I've also read that using interface is more OOP. How?
Cordially On Tue, Aug 26, 2008 at 2:23 AM, ben gomez farrell <[EMAIL PROTECTED]>wrote: > Hey I don't know what kind of development teams your working with, but I've > found that on small one off projects done with a small team, they aren't > that important. It's more of a big team, long term project, lotsa code type > thing. > > You can absolutely go with never using them, but it's a nice thing to > learn, and starts to get useful with AS3 type checking. > > So, an interface file is like a contract you are setting up with your code. > An interface (and you can see the syntax in your books), consists of public > variables and functions and their return types. These functions don't do > anything in the interface itself, that is they don't run. > > Where your interfaces get used is when you have a class that "implements" > one of your interfaces. So lets say you have MyClass extends MySuperClass > implements IMyInterface. (by convention interface files start with I....etc, > but of course you don't have to) > > So, for your project to even compile (when you implement an interface), > you'd better be damn sure that your "MyClass" has all the functions and > variables YOU defined in IMyInterface > It seems limiting, but, on a large team, you might have a dozen developers > creating a hundred or so classes that are all supposed to plugin somewhere > in your main project. If you create an interface, and make it known that > all developers must implement your interface, you can be sure that your > dozen developers and your hundred classes are going to have the methods that > YOU need to work in your project. > > And then if you make a large scale change to your project - you can just > change the interface - maybe add another method to it that you need for > additional functionality. If your dozen developers update to the new > interface file, all their code won't compile anymore - and they'll have to > update to your new methods before they get a compile! > > So it's handy on large teams. > > I've also found it handy for typecasting in AS3. Sometimes I might have 2 > classes that do sort of the same thing, but not quite. Maybe I have a mix of > several similar (but not identical) objects in an array, and I want to loop > through. > > So for example: list = [ myClassA, myClassB, myClassC, myClassA, myClassB, > myClassC, myClassA, myClassB, myClassC ]; > Now I loop through my objects, and I want to assign them to like a > temporary variable and perform an action on them. > > So.... var temp = list[c]; > But what do you type temp...you could do > var temp:* = list[c] > > And you could put anything you wanted in the variable. But we have type > casting in AS3 for a reason! > > You could create an interface full of the common methods and variables uses > by myClass A,B and C, make those classes implement your interface, and then > do your typecasting as this: > > var temp:IMyClasss = list[c]; > > Then you aren't using the wildcard to type your object AND you'll get > auto-complete for code, and compile time checking of anything you're trying > to do to your class that isn't supported. > > Hope this helps! > ben > > > > Omar Fouad wrote: > >> This could seem weird... >> But what the hell is an interface!!!???????? I've read lots of books and >> posts without getting the answer. I bought "Essential AS3" to read about >> interfaces and he says that helps for multi inheritance. In other places I >> read that it is a "deal" to ensure that a class has some methods and so >> on. >> But what is the real benefit that I can come out with using interfaces???? >> >> Maybe that is stupidity or I am not smart enough to get the concept but >> believe me... its is been two years now!! >> >> Please Help!!! >> >> >> > _______________________________________________ > Flashcoders mailing list > Flashcoders@chattyfig.figleaf.com > http://chattyfig.figleaf.com/mailman/listinfo/flashcoders > -- Omar M. Fouad - Digital Emotions http://www.omarfouad.net This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Thank you. _______________________________________________ Flashcoders mailing list Flashcoders@chattyfig.figleaf.com http://chattyfig.figleaf.com/mailman/listinfo/flashcoders
