'NSPersistentContainer'仅适用于iOS 10.0或更新

Question

我是IOS应用开发新手。我开发了一个应用程序，显示用户登录网站。它适用于部署目标设置为10.1。为了使它与IOS 8兼容，我试图将部署目标设置为8，因为我在其中出现错误。

'NSPersistentContainer' is only available on iOS 10.0 or newer 

任何人都可以使用的代码是什么，我需要改变，使其与IOS兼容帮助8,9 的Xcode 8.2.1 斯威夫特版本：3.2

import UIKit 
import CoreData 

@UIApplicationMain 

class AppDelegate: UIResponder, UIApplicationDelegate { 

    var window: UIWindow? 


    func application(_ application: UIApplication,didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool { 
     // Override point for customization after application launch. 
     return true 
    } 

    func applicationWillResignActive(_ application: UIApplication) { 
     // Sent when the application is about to move from active to inactive state. This can occur for certain types of temporary interruptions (such as an incoming phone call or SMS message) or when the user quits the application and it begins the transition to the background state. 
     // Use this method to pause ongoing tasks, disable timers, and invalidate graphics rendering callbacks. Games should use this method to pause the game. 
    } 

    func applicationDidEnterBackground(_ application: UIApplication) { 
     // Use this method to release shared resources, save user data, invalidate timers, and store enough application state information to restore your application to its current state in case it is terminated later. 
     // If your application supports background execution, this method is called instead of applicationWillTerminate: when the user quits. 
    } 

    func applicationWillEnterForeground(_ application: UIApplication) { 
     // Called as part of the transition from the background to the active state; here you can undo many of the changes made on entering the background. 
    } 

    func applicationDidBecomeActive(_ application: UIApplication) { 
     // Restart any tasks that were paused (or not yet started) while the application was inactive. If the application was previously in the background, optionally refresh the user interface. 
    } 

    func applicationWillTerminate(_ application: UIApplication) { 
     // Called when the application is about to terminate. Save data if appropriate. See also applicationDidEnterBackground:. 
     // Saves changes in the application's managed object context before the application terminates. 
     self.saveContext() 
    } 

    // 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: "testProject") 
     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 
    }() 

    // MARK: - Core Data Saving support 

    func saveContext() { 
     let context = persistentContainer.viewContext 
     if context.hasChanges { 
      do { 
       try context.save() 
      } catch { 
       // 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. 
       let nserror = error as NSError 
       fatalError("Unresolved error \(nserror), \(nserror.userInfo)") 
      } 
     } 
    } 

    } 

Answer 1

后的天搜索这里我得到了解决办法... 就在appdelegate.swift文件替换为下面的内容......它的工作..

// MARK: - Core Data stack 

@available(iOS 10.0, *) 
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: "coreDataTestForPreOS") 
    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 
}() 

// iOS 9 and below 
lazy var applicationDocumentsDirectory: URL = { 

    let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask) 
    return urls[urls.count-1] 
}() 

lazy var managedObjectModel: NSManagedObjectModel = { 
    // The managed object model for the application. This property is not optional. It is a fatal error for the application not to be able to find and load its model. 
    let modelURL = Bundle.main.url(forResource: "coreDataTestForPreOS", withExtension: "momd")! 
    return NSManagedObjectModel(contentsOf: modelURL)! 
}() 

lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator = { 
    // The persistent store coordinator for the application. This implementation creates and returns a coordinator, having added 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. 
    // Create the coordinator and store 
    let coordinator = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel) 
    let url = self.applicationDocumentsDirectory.appendingPathComponent("SingleViewCoreData.sqlite") 
    var failureReason = "There was an error creating or loading the application's saved data." 
    do { 
     try coordinator.addPersistentStore(ofType: NSSQLiteStoreType, configurationName: nil, at: url, options: nil) 
    } catch { 
     // Report any error we got. 
     var dict = [String: AnyObject]() 
     dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data" as AnyObject? 
     dict[NSLocalizedFailureReasonErrorKey] = failureReason as AnyObject? 

     dict[NSUnderlyingErrorKey] = error as NSError 
     let wrappedError = NSError(domain: "YOUR_ERROR_DOMAIN", code: 9999, userInfo: dict) 
     // Replace this with code to handle the error appropriately. 
     // abort() 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. 
     NSLog("Unresolved error \(wrappedError), \(wrappedError.userInfo)") 
     abort() 
    } 

    return coordinator 
}() 

lazy var managedObjectContext: NSManagedObjectContext = { 
    // Returns the managed object context for the application (which is already bound to the persistent store coordinator for the application.) This property is optional since there are legitimate error conditions that could cause the creation of the context to fail. 
    let coordinator = self.persistentStoreCoordinator 
    var managedObjectContext = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType) 
    managedObjectContext.persistentStoreCoordinator = coordinator 
    return managedObjectContext 
}() 

// MARK: - Core Data Saving support 

func saveContext() { 

    if #available(iOS 10.0, *) { 

     let context = persistentContainer.viewContext 
     if context.hasChanges { 
      do { 
       try context.save() 
      } catch { 
       // 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. 
       let nserror = error as NSError 
       fatalError("Unresolved error \(nserror), \(nserror.userInfo)") 
      } 
     } 
    } else { 
     // iOS 9.0 and below - however you were previously handling it 
      if managedObjectContext.hasChanges { 
       do { 
        try managedObjectContext.save() 
       } catch { 
        // Replace this implementation with code to handle the error appropriately. 
        // abort() 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. 
        let nserror = error as NSError 
        NSLog("Unresolved error \(nserror), \(nserror.userInfo)") 
        abort() 
       } 
      } 

     } 
    } 


}