The document discusses the use of Swift enums to enhance the safety and management of UICollectionViews and UITableViews, presented by Ariel Elkin at a Swift Berlin meetup. It highlights the complexities and disadvantages of traditional layout management, such as hard-coded values and fragmented layout information. By utilizing enums, the document suggests natural error handling, improved exhaustivity, and better decoupling in layout structures.

1. Using
Swift Enums
for safer
UICollectionViews
and
UITableViews
swift.berlin meetup
November 30, 2015
Ariel Elkin

2. PROJECT A
• Early-stage investor and company builder
• Marketplaces, E-commerce, Saas
• 20+ companies in our portfolio

3. ME
• iOS Developer in Project A’s Mobile Team
• 10+ apps in the App Store
• Puts his dishes in the dishwasher

4. COLLECTION VIEWS ARE COMPLEX
• section numbers
• item sizes
• section count
• reuse identifiers
• etc…

5. MANAGING THE LAYOUT STRUCTURE
• Typically involves hard-coding
integer values

6. MANAGING THE LAYOUT STRUCTURE
• Layout information is
fragmented
DISADVANTAGES

7. MANAGING THE LAYOUT STRUCTURE
• We have to manually ensure
that checks are exhaustive
DISADVANTAGES

8. MANAGING THE LAYOUT STRUCTURE
• Error handling not included
DISADVANTAGES

9. THE LAYOUT
STRUCTURE?
HOW CAN THE
COMPILER HELP US WITH

10. ENUMS

11. ENUMS
• turn the layout structure
into a type

12. NATURAL ERROR-HANDLING
ENUMS

13. EXHAUSTIVITY
ENUMS

14. EXHAUSTIVITY
ENUMS

15. ENUM FUNCTIONS AND PROPERTIES
ENUMS

16. COUNT
ENUMS

17. AUTOCOMPLETION GOODNESS
ENUMS

18. DEMO

19. FAVOUR DECOUPLING
ENUMS

20. THANK YOU!

21. QUESTIONS?