不称为境界迁移

我已经为一个领域对象添加了一个值(我已将动态var inspectorName =""添加到WeekReport对象中),我正在尝试迁移领域数据库以包含该值.我试图func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey : Any]? = nil)像这样调用迁移块:

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
    print("HERE")
    Realm.Configuration.defaultConfiguration = Realm.Configuration(
        schemaVersion: 1,
        migrationBlock: { migration, oldSchemaVersion in
            if (oldSchemaVersion < 1) {
                migration.enumerateObjects(ofType: WeekReport.className()) { oldObject, newObject in
                    newObject!["inspectorName"] = ""
                }
            }
    })

    return true
}

但似乎didFinishLaunchingWithOptions在我的错误发生之前没有调用.

在多视图控制器中我有let realm = try! Realm().我运行应用程序时Xcode中断了:

"由于以下错误,需要迁移: - 已添加属性'WeekReport.inspectorName'." UserInfo = {NSLocalizedDescription =由于以下错误而需要迁移: - 已添加属性'WeekReport.inspectorName'.,错误代码= 10}:file /Library/Caches/com.apple.xbs/Sources/swiftlang/swiftlang- 800.0.63/src目录/快捷/

怎么没有调用迁移blick？"HERE"从未打印过......

我应该在视图控制器中以不同的方式定义领域吗？

如果您将let realm = try! Realm()视图控制器作为实例变量编写，它将在application: didFinishLaunchingWithOptionsStoryboard 之前被调用。要解决此问题，可以lazy var realm = try! Realm()改用。lazy推迟创建实例变量，直到访问该变量为止。