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swiftuitableviewcore-datansfetchedresultscontroller

FetchedResultsController values are not overwriting custom NSManagedObject init values

I'm using a NSFetchedResultsController to get data from CoreData and load a table view with four sections. It works perfectly when the app is run for the first time, loading a plist into CoreData and then fetching records to configure cells in 4 sections of a table.

The problem occurs when I restart the app, init values from the class appear to overwrite the values that I thought/think were stored in core data. Values that are not initialized by the class are successfully loaded by the NSFetchedResultsController.

For example, there is a value, tableSection, to define table sections. When the table loads for the very first time, it has the four sections:

enter image description here

BUT, if I run the app again, there is only 1 tableSection value, 'My Records' (a default value intended for when the user first creates a record):

enter image description here

I'm not sure, but I figure this happens when I configure the cell...

func configureCell(cell: UITableViewCell, indexPath: NSIndexPath)
{
    let record = fetchedResultsController.objectAtIndexPath(indexPath) as! Record ...}

It looks like when the custom class is initiated the init values are assigned and never overwritten by the values I thought would be in the fetchedResultsContainer. Anything not given a value in the custom class init, like the text and image, are assigned values from the fetchedResultsController:

    class Record: NSManagedObject
{
    override init(entity: NSEntityDescription, insertIntoManagedObjectContext context: NSManagedObjectContext?)
    {
        super.init(entity: entity, insertIntoManagedObjectContext: context)
        let randomBit = String(arc4random_uniform(100))
        iD = NSDate().toIDTimeDateString() + "-" + randomBit + "OtR"

        believers = 0
        deviceTime = NSDate()
        doubters = 0
        eventTimeStarted = NSDate()
        eventTimeEnded = NSDate()
        featureImageIndex = 0
        coreLocationUsed = 0
        photoTaken = 0
        tableSection = "My Records"
        timeRecorded = deviceTime
        validationScore = 0
    }
}

How do I instantiate a 'Record' in a way that will overwrite the init values with the data from the fetchedResultsController? (if this is my problem)

Solution

  • Do not set values for a NSManagedObject in the init method. A NSManagedObject gets populated after the init is called. If you need to override values then do so in the awakeFromFetch or awakeFromInsert methods.

    I would strongly suggest reviewing the Core Data Programming Guide on what to override.