UnitConverter
Level 2, Eleven Lessons
Teach students about delegates, delegation and protocols through the creation of a programming classic. Facilitate a deeper understanding of Model-View-Controller, and demonstrate how to persist data with NSUserDefaults.
The Finished App
Familiarize yourself with the project, and demonstrate the app students will build.
Lesson 1
Discuss interface elements and user interaction. Introduce the picker view interface element.
Lesson 2
Use the UIPickerViewDataSource protocol as a vehicle for explaining Swift protocols.
Lesson 3
Use the UIPickerViewDelegate protocol to explain delegates and delegation.
Lesson 4
Leverage a mutable array of values to lead a refactoring from loops to an introduction of map.
Lesson 5
Facilitate implementing a delegate method to update a controller outlet.
Lesson 6
Analyze controller code to determine what should be extracted into a model.
Lesson 7
Introduce the concept of a "view model," and demonstrate adding custom objects that serve the view.
Lesson 8
Lead a refactoring to re-integrate the view, view model, and controller.
Lesson 9
Analyze app usability, and lead an implementation change to the interface for an improved initial state.
Lesson 10
Explain the NSUserDefaults API for storing and retrieving app data.
Lesson 11
Demonstrate loading date with the NSUserDefaults API, and resolve a subtle bug to illustrate type casting and optional binding.
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