The Basic MVC Model

Model

-- State data for each component.

• Different for each component
• E.g. Scrollbar -- Max and minimum Values, Current Position, width of thumb position relative to values
• E.g. Menu -- Simple List of items.
• Model data is always independent of visual representation.

View

-- How component is painted on the screen

• Can vary between platforms/look and feel

Controller

-- dictates how component interacts with events

• Many forms of events -- mouse clicks, keyboard, focus, repaint etc..
• Controller decides how component reacts to an event -- if at all

The three elements interact as follows:

The MVC Communication Model