Learning Swift Data

Created	2025-01-06T07:56:00Z
Updated	2025-01-11T17:23:20Z
Type	Research
Status	In Progress

• ModelConfiguration - used to configure the data store, name, location etc.
• ModelContainer - is responsible for creating and managing the underlying SQLite database file and maintaining data synchronisation.
• ModelContext - tracks, in memory the model objects that have been created, modified or deleted. It will inform the ModelContainer about those objects so that any changes can be committed to the database.

Basic Data Model

import Foundation
import SwiftData

@Model
class ChildModel {
    var name: String

    init(name: String) {
        self.name = name
    }
}

Hierarchical Data Model

import Foundation
import SwiftData

@Model
class ParentModel {
    var name: String
    var details: String
    var date: Date
    @Relationship(deleteRule: .cascade) var children = [ChildModel]()

    init(name: String = "", details: String = "", date: Date = .now) {
        self.name = name
        self.details = details
        self.date = date
    }
}

Application Reference to Data Model

import SwiftData
import SwiftUI

@main
struct AppName: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
        .modelContainer(for: ParentModel.self)
    }
}

The modelContainer() modifier tells SwiftData that it should:

• Create the storage for our data model object, or load it if it was created previously.
• Use that storage for the data inside the window group.

Now add this new property to the ContentView struct:

@Query var datamodels: [DataModel]