managedObjectContext in Swift 3

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故里飘歌
故里飘歌 2021-02-19 23:30

I want to work through this example code in which Swift and CoreData is used to create a table. However, using Swift 3 I fail to get it to work. Most importantly, I cannot prope

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  •  囚心锁ツ
    2021-02-20 00:24

    AppDelegate has below members only

    // MARK: - Core Data stack
    
    lazy var persistentContainer: NSPersistentContainer = {
        /*
         The persistent container for the application. This implementation
         creates and returns a container, having loaded the store for the
         application to it. This property is optional since there are legitimate
         error conditions that could cause the creation of the store to fail.
        */
        let container = NSPersistentContainer(name: "")
        container.loadPersistentStores(completionHandler: { (storeDescription, error) in
            if let error = error as NSError? {
                // Replace this implementation with code to handle the error appropriately.
                // fatalError() causes the application to generate a crash log and terminate. You should not use this function in a shipping application, although it may be useful during development.
    
                /*
                 Typical reasons for an error here include:
                 * The parent directory does not exist, cannot be created, or disallows writing.
                 * The persistent store is not accessible, due to permissions or data protection when the device is locked.
                 * The device is out of space.
                 * The store could not be migrated to the current model version.
                 Check the error message to determine what the actual problem was.
                 */
                fatalError("Unresolved error \(error), \(error.userInfo)")
            }
        })
        return container
    }()
    

    so use

     let managedContext = (UIApplication.shared.delegate as! appDelegate).persistentContainer.viewContext
    

    This will work fine

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