由于核心数据迁移，iOS应用在启动屏幕上崩溃

Question

This is the code:

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
}

This is the error I am getting.

returned error Error Domain=NSCocoaErrorDomain Code=134110 "An error occurred during persistent store migration." UserInfo={sourceURL=file:///var/mobile/Containers/Data/Application/2963C60A-11D3-4A6F-9496-623F5EFCFCB1/Documents/me.gundmi@abc.in.sqlite, reason=Can't copy source store to destination store path, destinationURL=file:///var/mobile/Containers/Data/Application/2963C60A-11D3-4A6F-9496-623F5EFCFCB1/Documents/.me.gundmi@abc.in.sqlite.migrationdestination_41b5a6b5c6e848c462a8480cd24caef3, NSUnderlyingError=0x1c4a40480 {Error Domain=NSCocoaErrorDomain Code=516 "The file “.me.gundmi@abc.in.sqlite.migrationdestination_41b5a6b5c6e848c462a8480cd24caef3” couldn't be saved in the folder “Documents” because a file with the same name already exists." UserInfo={NSFilePath=/var/mobile/Containers/Data/Application/2963C60A-11D3-4A6F-9496-623F5EFCFCB1/

Answer 1

如果它们很大，则您可能要考虑控制迁移，并将其放在后台线程中或将其分解成几部分，以便应用程序可以按时启动。