Developing Your App’s User Interface
In This Chapter
Understanding how user interfaces are built in iOS
Using the common user-interface elements provided by the iOS framework
Understanding the OO principles underlying user interfaces
This chapter focuses on developing the user interface (or UI) of your iOS app. I briefly discuss the theory behind how the UI works. Then I explain how iOS implements user interfaces, starting with the Application object, and how user-interface events (such as touches) are transmitted down the responder chain.
I go over the Model-View-Controller (MVC), which is layered on the responder chain and is the dominant pattern used in iOS user interfaces. Next, I cover several components that Apple makes available in the iOS framework that you can use in developing your apps. Finally, I tie these patterns and components to OO techniques, concepts, and design principles.
Understanding How User Interfaces Work in iOS
In this section, I explain event-driven programming, an approach that is fundamental to developing applications with rich graphical user interfaces. I also explain how iOS handles events.