The document discusses strategies for dealing with JSON data in Realm Swift. It notes that Realm does not allow nil values, so optional properties with default values are recommended. It also suggests using raw values for enums. The document outlines methods for creating or updating objects from JSON that will skip nil values rather than throwing exceptions. These include createInDefaultRealmWithValue and addObject. It notes Realm may support nil values in the future.

1. Advanced Realm in Swift
trippiece Inc.
@kitasuke

2. Table of contents
• Introducing Realm Swift
• How to deal with JSON

3. Before starting a presentation,
I would like to introduce my new
library

5. Flexible menu width mode
PagingEnabled mode

6. Fixed menu width mode
ScrollingEnabled mode
centerItem option

7. SegmentedControl mode

8. Usage
let viewController = self.storyboard?.instantiateViewControllerWithIdentifier("ViewController") as! ViewController
viewController.title = "Menu title"
let viewControllers = [viewController]
let options = PagingMenuOptions()
let pagingMenuController = self.childViewControllers.first as! PagingMenuController // there is a containerView having a childViewController in storyboard
pagingMenuController.setup(viewControllers: viewControllers, options: options)

9. Customization
public class PagingMenuOptions {
public var defaultPage = 0
public var backgroundColor = UIColor.whiteColor()
public var selectedBackgroundColor = UIColor.whiteColor()
public var textColor = UIColor.lightGrayColor()
public var selectedTextColor = UIColor.blackColor()
public var font = UIFont.systemFontOfSize(16)
public var menuHeight: CGFloat = 50
public var menuItemMargin: CGFloat = 20
public var animationDuration: NSTimeInterval = 0.3
public var menuDisplayMode = MenuDisplayMode.FlexibleItemWidth(centerItem: true, scrollingMode: MenuScrollingMode.PagingEnabled)
public var menuItemMode = MenuItemMode.Underline(height: 3.0, color: UIColor.whiteColor(), selectedColor: UIColor.blueColor())
public enum MenuScrollingMode {
case ScrollEnabled
case ScrollEnabledAndBouces
case PagingEnabled
}
public enum MenuDisplayMode {
case FlexibleItemWidth(centerItem: Bool, scrollingMode: MenuScrollingMode)
case FixedItemWidth(width: CGFloat, centerItem: Bool, scrollingMode: MenuScrollingMode)
case SegmentedControl
}
public enum MenuItemMode {
case None
case Underline(height: CGFloat, color: UIColor, selectedColor: UIColor)
case RoundRect
}
}

10. Welcome your feedback!
https://github.com/kitasuke/PagingMenuController

11. Back to Realm

12. Realm Swift released
A full-fledged, Swift-native API
Introducing Realm Swift

13. Available through Dynamic
Framework, CocoaPods and
Carthage
Documentation for Realm Swift

14. What's the difference between
Swift bridge from Objective-C
and
purely Swift?

15. Swift bridge
class Employee: RLMObject {
dynamic var name = "" // you can specify defaults
dynamic var startDate = NSDate()
dynamic var salary = 0.0
dynamic var fullTime = true
}
class Company: RLMObject {
dynamic var name = ""
dynamic var ceo: Employee? // optional to-one relationship
let employees = RLMArray(objectClassName: Employee.className()) // to-many relationship
}
purely Swift
class Employee: Object {
dynamic var name = "" // you can specify defaults
dynamic var startDate = NSDate()
dynamic var salary = 0.0
dynamic var fullTime = true
}
class Company: Object {
dynamic var name = ""
dynamic var ceo: Employee? // optional to-one relationship
let employees = List<Employee>() // generic to-many relationship
}

16. Swift bridge
let company = Company() // Using Realm Objects
company.name = "Realm Inc."
let realm = RLMRealm.defaultRealm() // Default Realm
realm.transactionWithBlock({ () -> Void in // Transactions
realm.addObject(company)
})
// Queries
let company = Company.allObjects().firstObject() as! Company
company.name // => "Realm Inc." (property access is type-safe)
let ftJacks = Employee.objectsWhere("name = 'Jack'").objectsWhere("fullTime = true") // RLMResults
purely Swift
let company = Company() // Using Realm Objects
company.name = "Realm Inc."
let realm = Realm() // Default Realm
realm.write { // Transactions
realm.add(company)
}
// Queries
let companies = realm.objects(Company) // => Results<Company>
companies[0].name // => "Realm Inc." (property access is type-safe)
// "Jack"s who work full time (lazily loaded & chainable)
let ftJacks = realm.objects(Employee).filter("name = 'Jack'")
.filter("fullTime = true")

17. Cannot use full Swift features like
enum yet, but it's definitely
better than before

18. Dealing with JSON in Swift

19. Not sure exactly what kind of
values server respond

20. Might be Array, String, Int or nil

21. However, Realm doesn't accept nil

22. Make it Optional and Set default values
class Employee: Object {
dynamic var name: String? = ""
dynamic var startDate: NSDate? = NSDate()
dynamic var salary: double? = 0.0
dynamic var fullTime: Bool? = true
}

23. Use rawValue for enum
class Employee: Object {
dynamic var type: Int = Type.iOS.rawValue
enum Type: Int {
case iOS = 1
case Android = 2
}
}

24. ignoredProperty could be useful
class Employee: Object {
var number: Int = 0
var name: String { // computed properties are automatically ignored
return "String"
}
override static func ignoredProperties() -> [String] {
return ["number"]
}
}

25. That's for object mapping so far

26. Next one is the biggest problem

27. nil cannot be saved in Realm

28. If you save nil in Realm,
an exception will be thrown

29. Ideally, values should be saved,
but nil should be skipped

30. Use following methods with external data
• createInDefaultRealmWithValue:
• createInRealm: withValue:
• createOrUpdateInDefaultRealmWithValue:
• createOrUpdateInRealm: withValue:
• create(type: T.Type, value: AnyObject = [:],
update: Bool = false) in Realm Swift

31. if not exists in Realm yet,
default value is used for key,
otherwise it's skipped

32. Use following methods with realm object
• addObject:
• addObjects:
• addOrUpdateObject:
• addOrUpdateObjectsFromArray:
• add(object: Object, update: Bool = false) in Realm
Swift
• add(objects: S, update: Bool = false) in Realm Swift

33. Realm might support nil soon,
so keep it mind that
this is just a workaround

34. Any questions?