Where should NSManagedObjectContext be created?

Question

I\'ve recently been learning about Core Data and specifically how to do inserts with a large number of objects. After learning how to do this and solving a memory leak probl

Answer 1

This is a supplemental answer to @JodyHagins' answer. I am providing a Swift implementation of the pseudocode that was provided there.

let managedObjectContext = NSManagedObjectContext(concurrencyType: NSManagedObjectContextConcurrencyType.PrivateQueueConcurrencyType)
managedObjectContext.persistentStoreCoordinator = (UIApplication.sharedApplication().delegate as! AppDelegate).persistentStoreCoordinator // or wherever your coordinator is

managedObjectContext.performBlock { // runs asynchronously

    while(true) { // loop through each batch of inserts

        autoreleasepool {
            let array: Array? = getNextBatchOfObjects()
            if array == nil { break }
            for item in array! {
                let newEntityObject = NSEntityDescription.insertNewObjectForEntityForName("MyEntity", inManagedObjectContext: managedObjectContext) as! MyManagedObject
                newObject.attribute1 = item.whatever
                newObject.attribute2 = item.whoever
                newObject.attribute3 = item.whenever
            }
        }

        // only save once per batch insert
        do {
            try managedObjectContext.save()
        } catch {
            print(error)
        }

        managedObjectContext.reset()
    }
}

These are some more resources that helped me to further understand how the Core Data stack works:

• Core Data Stack in Swift – Demystified
• My Core Data Stack