由于核心数据迁移，iOS 应用程序在启动屏幕上崩溃

Question

这是代码：

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.
    let filemgr = FileManager.default

    let documentDirectoryURL = try! FileManager.default.url(for: .documentDirectory,
                                                            in: .userDomainMask,
                                                            appropriateFor: nil,
                                                            create: true)
    let databaseURL = documentDirectoryURL.appendingPathComponent(“def.sqlite")
    var error1 : NSError?
    let fileExists = (databaseURL as NSURL).checkResourceIsReachableAndReturnError(&error1)
    if(fileExists){
        self.copyFile()
    }
    var myOptions = Dictionary<String, Any>()
    myOptions[NSMigratePersistentStoresAutomaticallyOption] = true
    myOptions[NSInferMappingModelAutomaticallyOption] = true
    var coordinator: NSPersistentStoreCoordinator? = NSPersistentStoreCoordinator(managedObjectModel: self.managedObjectModel)
    let ext = ".sqlite"
    let url = self.applicationDocumentsDirectory.appendingPathComponent((Utils.getPreferenceValue(ForKey: Constants.LOGIN_USER_NAME))+ext)//".sqlite")

    var error: NSError? = nil
    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: myOptions)
    } catch var error1 as NSError {
        error = error1
        coordinator = nil
        // 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
        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()
    } catch {
        fatalError()
    }

    return coordinator
}

这是我遇到的错误。

返回错误 Error Domain=NSCocoaErrorDomain Code=134110 "一个错误 在持久存储迁移期间发生。” UserInfo={sourceURL=file:///var/mobile/Containers/Data/Application/2963C60A-11D3-4A6F-9496-623F5EFCFCB1/Documents/me.gundmi@abc.in.sqlite, 原因=无法将源存储复制到目标存储路径， destinationURL=file:///var/mobile/Containers/Data/Application/2963C60A-11D3-4A6F-9496-623F5EFCFCB1/Documents/.me.gundmi@abc.in.sqlite.migrationdestination_41b5a6b5c6e848c462a8480cd24caef3, NSUnderlyingError=0x1c4a40480 {错误域=NSCocoaErrorDomain 代码=516 "文件 “.me.gundmi@abc.in.sqlite.migrationdestination_41b5a6b5c6e848c462a8480cd24caef3” 无法保存在“文档”文件夹中，因为带有 同名已经存在。” UserInfo={NSFilePath=/var/mobile/Containers/Data/Application/2963C60A-11D3-4A6F-9496-623F5EFCFCB1/

Answer 1

如果它们非常大，那么您可能需要考虑控制迁移并将其置于后台线程或将其分解为多个部分，以便应用程序可以按时启动。