Core Principles

• Minimize script block logic in MXML, extract into behaviour objects following Single Responsibility Principle.
• Prefer small classes with high functional cohesion (every method refers to all properties).
• Show the intent of code clearly. Understand options in loose coupling and apply when motivations are clear.
• Allow modular development and testing; organize by functional areas, control and limit dependencies between functional areas, extract and control shared infrastructure.
• Perform automated, functional testing.
• Perform automated unit testing and differentiate from automated functional testing; emphasize on behaviour instead of structure and wiring.
• Control quality and streamline a release with build automation.
• Prefer convention over configuration.
• Create genuinely reusable view and non-visual (i.e. formatters, validators, log targets) components only using Flex SDK APIs without domain or IoC framework knowledge.

References

Martin, R. Single Responsiblity Principle. http://www.objectmentor.com/resources/articles/dip.pdf of OOD principles .