modello di dati Xcode 8 core per iOS 8,9

Question

Sto sviluppando un'applicazione in un nuovo Xcode 8 e ho notato una cosa ovvia. Xcode mi ha generato i dati principali con gli ultimi riferimenti API. Quindi, se cambio obiettivo di distribuzione su iOS 8 o 9, esso è in conflitto e mi propone di prendere tra parentesi: AVAILABLE il mio codice di dati di base. Ciò significa che devo scrivere da zero il codice Core Data dalla precedente API. Qualcuno ha un template per AppDelegate con entrambi o forse è possibile renderlo Xcode? Grazie in anticipo!

Answer 1

Perché nessuno dovrebbe avere a scaricare Xcode 7, installarlo, avviare un nuovo progetto, e la porta il codice modello per swift 3 solo per utilizzare i dati di base, pur sostenendo iOS 8 & 9:

Swift 2 core metodi di modello di dati da AppDelegate.swift:

lazy var applicationDocumentsDirectory: NSURL = { 
    // The directory the application uses to store the Core Data store file. This code uses a directory named "com.cadiridris.coreDataTemplate" in the application's documents Application Support directory. 
    let urls = NSFileManager.defaultManager().URLsForDirectory(.DocumentDirectory, inDomains: .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 = NSBundle.mainBundle().URLForResource("coreDataTemplate", withExtension: "momd")! 
    return NSManagedObjectModel(contentsOfURL: 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.URLByAppendingPathComponent("SingleViewCoreData.sqlite") 
    var failureReason = "There was an error creating or loading the application's saved data." 
    do { 
     try coordinator.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: url, options: nil) 
    } catch { 
     // Report any error we got. 
     var dict = [String: AnyObject]() 
     dict[NSLocalizedDescriptionKey] = "Failed to initialize the application's saved data" 
     dict[NSLocalizedFailureReasonErrorKey] = failureReason 

     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 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() 
     } 
    } 
} 

convertiti in rapida 3:

lazy var applicationDocumentsDirectory: URL = { 
    // The directory the application uses to store the Core Data store file. This code uses a directory named "com.cadiridris.coreDataTemplate" in the application's documents Application Support directory. 
    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: "coreDataTemplate", 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 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() 
     } 
    } 
} 

Answer 2

Grazie a DCToDaylight's answer. Ho creato questo file, che puoi semplicemente trascinare e rilasciare. Ho anche reso statico il mio oggetto gestito, e il mio metodo init privato. In modo che qualcuno non possa istanziare accidentalmente un nuovo contesto.

La funzione chiamata getContext rende più facile ogni volta che fate qualcosa con i dati di base.

l'idea di creare un managedObjectContext statica, un file separato e la funzione è venuto da this YouTube tutorial.

Per questo esempio ho fatto un nuovo file chiamato DatabaseController.swift e mettere tutto questo codice in là. Questo renderà il mio codice più semplice da gestire e leggere. Puoi anche copiare dallo // MARK: - Core Data stack in fondo al file e sostituire il codice simile in te AppDelegate.swift e funzionerà.

import Foundation 
import CoreData 

class DatabaseController { 

    private init() { 

    } 

    class func getContext() -> NSManagedObjectContext { 
     return DatabaseController.managedObjectContext 
    } 
    // MARK: - Core Data stack 

    static var managedObjectContext: NSManagedObjectContext = { 

     var applicationDocumentsDirectory: URL = { 
      // The directory the application uses to store the Core Data store file. This code uses a directory named "com.cadiridris.coreDataTemplate" in the application's documents Application Support directory. 
      let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask) 
      return urls[urls.count-1] 
     }() 

     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: "YOUR_APP_NAME", withExtension: "momd")! 
      return NSManagedObjectModel(contentsOf: modelURL)! 
     }() 

     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: managedObjectModel) 
      let url = 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 
     }() 

     // 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 = persistentStoreCoordinator 
     var managedObjectContext = NSManagedObjectContext(concurrencyType: .mainQueueConcurrencyType) 
     managedObjectContext.persistentStoreCoordinator = coordinator 
     return managedObjectContext 
    }() 

    // MARK: - Core Data Saving support 

    class func saveContext() { 
     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() 
      } 
     } 
    } 
} 

Detto questo, per ovvie ragioni non è possibile utilizzare il NSPersistantContainer, quindi è necessario utilizzare il metodo Core Data Stack utilizzando la managedObjectContext.

Answer 3

Se si desidera una soluzione rapida per questo è sufficiente aggiungere una classe c obiettivo contenente la funzione generale dei dati di base per ottenere riferimenti a NSManagedObjectContext e NSPersistentStoreCoordinator. (Puoi trovare il codice su SO o su altro sito, Contattatemi nel caso in cui abbiate bisogno di quella classe.)

Dopo aver aggiunto la classe, usare la clausola @Available 10 e in un'altra parte aggiungere codice per fare riferimento al modello sopra menzionato.

Fatemi sapere se qualcuno ha trovato qualcosa di sbagliato con esso.