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iosswiftnsmanagedobjectinitializer

How to implement NSManagedObject class conforming to Mappable


I have a class that maps directly JSON implementing the Mappable (ObjectMapper Framework) protocol and I'm trying to inherit from NSManagedObject.

class AbstractModel: NSManagedObject, Mappable {

@NSManaged var uuid: String?
@NSManaged var updatedAt: String?
@NSManaged var createdAt: String?

required init?(_ map: Map) {
    mapping(map)
}

func mapping(map: Map) {
    uuid        <- map["uuid"]
    updatedAt   <- map["updatedAt"]
    createdAt   <- map["createdAt"]

}
}

The problem with this implementation is that the compiler complains about the mapping(map) that uses self before the super initializer: AbstractModel.swift:19:9: Use of 'self' in method call 'mapping' before super.init initializes self

Unfortunately I cannot call the super initializer (super.init(entity: NSEntityDescription, insertIntoManagedObjectContext: NSManagedObjectContext?)) before mapping(map) because I need self to get the NSManagedObjectContext.

How am I supposed to solve this problem?


Solution

  • I'm not sure if this solution is the proper way to solve the problem but I implemented my class that way and it worked:

    class AbstractModel: NSManagedObject, Mappable {
    
    @NSManaged var uuid: String?
    @NSManaged var updatedAt: String?
    @NSManaged var createdAt: String?
    
    override init(entity: NSEntityDescription, insertIntoManagedObjectContext context: NSManagedObjectContext?) {
        super.init(entity: entity, insertIntoManagedObjectContext: DBUtils().getManagedObjectContext())
    }
    
    required init?(_ map: Map) {
        var ctx = NSManagedObjectContext.MR_defaultContext()
        var entity = NSEntityDescription.entityForName("AbstractModel", inManagedObjectContext: ctx)
        super.init(entity: entity!, insertIntoManagedObjectContext: ctx)
    
        mapping(map)
    }
    
    func mapping(map: Map) {
        uuid        <- map["uuid"]
        updatedAt   <- map["updatedAt"]
        createdAt   <- map["createdAt"]
    
    }
    }