Using CoreData to save array containing dictionaries - ios

Question

I'm trying to use CoreData framework inside an iOS app for the first time and I have some troubles with it.
I have a kind of complex type of array, containing tuples that contains dictionaries:
let DataSet: [( Float, Float, [String : String])] = ...
I created an NSManagedObjectContext and an NSManagedObject, I added the DataSet array to the NSManagedObject, but when I try to save the 1st NSManagedObjectContext, the app is crashing.
That's not happening using normal arrays but only with more complex ones like the one above.
Is there a way to deal with that problem? Do I need to adjust my xcdatamodel?
I would appreciate any help a lot.

Answer 1

First you need to declare 2 separate entities. One for Floats and another for Dictionary.
Then create "One to Many" relation ship between Float entity and Dictionary. It will look like this,
Then you need to convert your tuple into these 2 entities, Like this,
dataSet.forEach{ (member) in
let tuple = Test.(context: mainContext)
tuple.first = member.0
tuple.second = member.1
let dictionary = member.2
dictionary.forEach{ (key, value) in
let dick = Dick.(context: mainContext)
dick.key = key
dick.value = value
tuple.addToContains(dick)
}
}
Finally you need to save the values.
if mainContext.hasChanges {
do {
try mainContext.save()
} catch {
print(\(error))
}
}