Question

我想在名为＆＃34;注册＆＃34;的核心数据文件中添加第二个实体。有两个实体1.Register 2.Hospital。当我在Persistancestorecoordinator＆＃34; abort（）＆＃34;中添加第二个实体，应用程序崩溃和指向错误时。

请给出与Swift相关的答案 AppDelegate有什么问题？

有人给了我不同的STACKOVERFLOW LINK但是没有与更新版本等有关的问题。 -i想在核心数据中添加第二个实体。 appdelegate是否有任何变化。

下面的代码在我的AppDelegate中：

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("Register", withExtension: "momd")!
    return NSManagedObjectModel(contentsOfURL: modelURL)!
    }()

lazy var persistentStoreCoordinator: NSPersistentStoreCoordinator? = {
    // The persistent store coordinator for the application. This implementation creates and return 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
    var coordinator: NSPersistentStoreCoordinator? = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
    let url = self.applicationDocumentsDirectory.URLByAppendingPathComponent("REDCROSSPROJECTS.sqlite")
    var error: NSError? = nil
    var failureReason = "There was an error creating or loading the application's saved data."
    if coordinator!.addPersistentStoreWithType(NSSQLiteStoreType, configuration: nil, URL: url, options: nil, error: &error) == nil {
        coordinator = nil
        // 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
        error = 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 \(error), \(error!.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
    if coordinator == nil {
        return nil
    }
    var managedObjectContext = NSManagedObjectContext()
    managedObjectContext.persistentStoreCoordinator = coordinator
    return managedObjectContext
    }()

Answer 1

您的问题可能与核心数据迁移有关。

在开发过程中，您只需从iPad或模拟器中删除应用程序，然后再次运行即可。

当您需要使用经过修改的核心数据模型发布新版本的应用时，您需要了解Core Data versioning and migration。

AppDelegate中第二个核心数据实体需要的任何代码？

1 个答案: