Prana Framework

Inversion of Control for ActionScript 3.0

Prana Framework 0.6 Released

Posted by Christophe Herreman on July 23, 2008

We’re pleased to announce that the Prana Framework 0.6 release is now available.

Prana

Download | API Documentation | Changelog

In this release the following remarkable changes and additions have been made:

  • the IoC container is now ActionScript 3 compatible
  • command factories for Cairngorm’s FrontController
  • more PureMVC experimenting

ActionScript 3 compatibility

We got lots of reactions from people who wanted to use Prana in ActionScript projects but couldn’t because Prana relied heavily on some Flex framework specific classes. Well, we have now resolved this issue by completely refactoring the IoC container and parser so that all Flex dependencies are removed. As a result we now have 2 different application context implementations. The first one is the standard XMLApplicationContext which is aimed to be ActionScript 3 compatible. The second one is the FlexXMLApplicationContext which actually extends the XMLApplicationContext and adds support for Flex specific classes like ArrayCollection. The application context and the XML parsers are now configurable with XML node parsers and reference resolvers so it would theoretically be possible now to extend the XML dialect with your own tags and have them parsed by the application context.

Command Factories for Cairngorm’s FrontController

In order to reach maximum flexibility in setting up commands and business delegates, we have introduced the option to create custom command factories that plug into Cairngorm’s FrontController. The FrontController actually allready acts as a command factory since it takes an event name, looks up its corresponding command and instantiates that command. We have abstracted that behavior so that it is now possible to write a custom implementation of a command factory and register it with the FrontController. This is very handy when you want commands to handle different implementations of business delegates without the need to instantiate a business delegate directly in a command, making it hard to test and change.

What follows is an example of a command that is configured with a business delegate at runtime via the IoC container.

[AS]public class AuthenticateUserCommand extends AbstractResponderCommand {
override public function execute(event:CairngormEvent):void {
super.execute(event);
var e:AuthenticateUserEvent = event as AuthenticateUserEvent;
IUserDelegate(businessDelegate).authenticate(e.username, e.password);
}
}[/AS]

[XML]






com.domain.commands.AuthenticateUserCommand
com.domain.commands.AuthenticateSSOUserCommand



[/XML]

Notice that we are registering the command factory with the FrontController via the “method-invocation” element. This is a new XML element that was introduced this release and that is actually preprocessed to a MethodInvokingFactoryObject.

Further, we are configuring the FrontController with a BusinessDelegateFactory which is available in the Prana Cairngorm extensions. We need to specify a name of the business delegate class we want the factory to create and also pass in a reference to the appropriate service. We also need to make clear to the FrontController what commands need to be created via this factory. As you can see we added 2 types of commands, a AuthenticateUserCommand and a AuthenticateSSOUserCommand.

When the FrontController receives an event, it will look up the corresponding command (just like it works in Cairngorm), but instead of creating a command via its class name on the fly, the controller will lookup the command factory it needs to use and then use that factory to create the command. In the example, a command will be created and a business delegate will be injected.

More PureMVC Experimenting

The Prana-PureMVC team has been playing around with some new ideas around better integration between the two frameworks. Some of the key changes and improvements are:

  • changes in internal implementation which are not so much visible from the end user standpoint, but can potentially have some impact on wider prana/puremvc acceptance
  • new feature which enables significant reduction of name constants during registration, retrieval and removal of puremvc elements (proxies, mediators and commands)
  • new feature which enables additional and different startup idiom with which prana can be initialized late instead of up front as it had to be before

For a full and in depth discussion on these changes, please see the text file at “prana-sample-anotherArch101Demo/resources/docs/pranaPureMvcIntegration-FurtherDevelopment.txt”.

Conclusion

We hope you enjoy this release and we are always interested to hear from you. So if you have any comments or suggestions, be sure to join our forum at http://prana.herrodius.com.

Hope you enjoy this release and have fun coding.

  1. Recent URLs tagged Actionscript - Urlrecorder Said,

    […] recorded first by kaysursozay on 2008-08-12→ Prana Framework 0.6 Released […]

  2. Moxie Said,

    Hi Chris, could you drop me a line. I’d like to talk to you about this framework.

    Moxie

Add A Comment