What are the Responsibilities of the Mediator Class in MVCS?

Flash, Flex and AIR applications provide virtually limitless possibilities for rich visual user interface components. All of these platforms provide out of the box components such as DataGrids, Buttons, Labels and other common UI components. It is also possible to extend these basic components into custom components, create composite components, or write components from scratch.

A View Component is any UI component and/or its sub-components. A View Component is encapsulated, handling its own state and operations as much as possible. A View Component provides an API via events, simple methods, and properties upon which Mediators act upon to affect the View Component within a Context. Mediators are responsible for interacting with the framework on behalf of the View Components that they mediate. This includes listening for Events on the components and their sub-components, accessing methods, and reading/setting properties on the components.

A Mediator listens for Events on its View Component, and accesses data directly on the View Component via its exposed API. A Mediators acts on behalf of other framework actors by responding to their Events and modifying its View Component accordingly. A Mediator notifies other framework actors of Events created by the View Component by relaying those Events, or dispatching appropriate Events to the framework.