---

Audio Units as Instances of the Model-View-Controller Design Pattern

Apple’s Core Audio team designed the Audio Unit technology around one of the more popular software design patterns, the Model-View-Controller, or MVC. See The Model-View-Controller Design Pattern for more about this pattern.

Keep the MVC pattern in mind as you build your audio units:

• The audio unit serves as the model, encapsulating all of the knowledge to perform the audio work

• The audio unit’s view serves, naturally, as the view, displaying the audio unit’s current settings and allowing a user to change them

• The Audio Unit Event API, and the code in an audio unit and its view that calls this API, corresponds to the controller, supporting communication between the audio unit, its view, and a host application

---