Rich Internet Applications, Flex, AIR, Java

In the first part of this series, we looked at how the “Spring ActionScript” framework can help you externalize the configuration and the wiring of your components, and how you can easily obtain configured objects using applicationContext.getObject().

In this second part, we will discuss how you can make these objects available to the views of your application without tightly coupling these views to the framework, and without passing references around through potentially many levels of view containment.

We will build the “Spring ActionScript” version of the InSync contact management application I often use in this blog to explore new technologies. The application has two views: MainView and ContactForm. Both need a reference to a contact RemoteObject to work.

NOTE: This example is intentionally kept simple. In a more partitioned application, you may want to pass a more abstract controller around as opposed to a specific RemoteObject. We will use this approach in part 3.

The views could use applicationContext.getObject() to access their dependencies (in this case the contact RemoteObject), but this approach has a number of problems:

1. With a dependency on applicationContext, the views would be tightly coupled to the framework.
2. We would still need to pass a reference to the applicationContext object to the views. This is often solved using the singleton approach which has its own set of problems.

So, instead of the views instantiating or looking up their dependencies, a better approach would be to “inject” these dependencies into the views.

Unlike Swiz, “Spring ActionScript” doesn’t currently have built-in support for an [Autowire] annotation, but Christophe Herreman seems to imply that this feature is coming, and in the meantime, he provides some sample code to support “Spring ActionScript”-powered autowiring in your application. Using this custom code, the inSync application looks like this:

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