Flex MVC options

The set of instructions in rich applications tends to get quite complex. Thus, RIA code needs to be divided up into smaller components to manage complexity. Design patterns such as MVC are loose methodologies for doing this, with limitless implementations in practice. In Flex, MVC are often referred to as microarchitectures. They manage business logic for a client application, allowing decoupling between logic and UI.

The prominent first generation of mature MVC framework for Flash and Flex is called Cairngorm. It is now up to 2.2 with version 3 hovering indefinitely in beta. Cairngorm introduces a new system of event management called the CairngormEvent. It is more analog than extension of a Flex Event, since it has unique dispatch and propagation attributes.

The pros and cons of isolated event management, MVC and FlexEvent, have been largely considered in the developer community, resulting in some rethinking of Cairngorm event methodology. A prominent advance is UniversalMind's UM Cairngorm Extensions. This represents first and foremost an enrichment of the Cairngorm framework. If you plan on going down this path, UM Extensions may allow you to do more with it.

Otherwise, Flex is reaching the second iteration of third party frameworks, as Cairngorm gets more competitors. Mate and Swiz lead the pack, with retooled and reconsidered architectures for events and business logic structures. In some cases, microarchitectures are fully MXML in the second iteration.

By no means is the solution one-sided, as many groups have invested heavily in their extant codebase. In any case, all the options deserve a thorough look see. Some orientation will allow you to consider the best for your project.