How do you assign a UUID in Swift?

Question

I am trying to follow the Model View ViewModel format for SwiftUI, but am running into an issue with UUID. I have an object of type TimeCode that has an attribute id of type UUID (TimeCode is created in xcdatamodels as a CoreData model). In order to create a TimeCodeViewModel object, I need to assign the id attribute in TimeCodeViewModel with the same UUID from the original TimeCode object. I therefore created this class definition to do so:

class TimeCodeViewModel: Identifiable {
    var id: UUID
    var fullName = ""
    
    
    init(timeCode: TimeCode) {
        self.id = timeCode.id
        self.fullName = timeCode.fullName
    }
    
    // class methods
}

However, I get a compile time error saying that UUID is a get-only property. This makes sense, since you shouldn't be able to reassign the unique ID of an object to a different object, but in this case I am actually trying to describe the same object. Is it possible to assign self.id with the same UUID?

I guess another approach could be to make the UUID a string and then assign it to the view model, but is it then possible to convert the string back into a UUID? For example, I want to fetch the original TimeCode from CoreData using the UUID from the TimeCodeViewModel so I can save edits to other attributes of the TimeCode.

Answer 1

It would be interesting to see how the TimeCode Class looks like. I don't think that the id is set correctly. If you want a unique identifier as a String add the following to generate one:

var id: String = UUID().uuidString

You can share the string and therefore reference to the same object.

EDIT: Regarding the new information, changing the class to the following might be an idea:

class TimeCodeViewModel: Identifiable {
   var id: UUID {
      return timeCode.id
   }
   var fullName = ""
   private var timeCode: TimeCode

   init(timeCode: TimeCode) {
      self.timeCode = timeCode
      self.fullName = timeCode.fullName
   }
   // class methods
 }