swift - 通过按钮强制与 iCloud 同步

Question

我的应用程序使用 iCloud 进行同步。在我的主视图 Controller 的 viewWillAppear 中:

// Configure persistant store on iCloud

    NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(TodayViewController.persistentStoreDidChange), name: NSPersistentStoreCoordinatorStoresDidChangeNotification, object: nil)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(TodayViewController.persistentStoreWillChange(_:)), name: NSPersistentStoreCoordinatorStoresWillChangeNotification, object: managedObjectContext.persistentStoreCoordinator)
    NSNotificationCenter.defaultCenter().addObserver(self, selector: #selector(TodayViewController.recieveICloudChanges(_:)), name: NSPersistentStoreDidImportUbiquitousContentChangesNotification, object: managedObjectContext.persistentStoreCoordinator)

和 viewWillDisappear:

override func viewWillDisappear(animated: Bool) {
    NSNotificationCenter.defaultCenter().removeObserver(self, name: NSPersistentStoreCoordinatorStoresDidChangeNotification, object: nil)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: NSPersistentStoreCoordinatorStoresWillChangeNotification, object: managedObjectContext.persistentStoreCoordinator)
    NSNotificationCenter.defaultCenter().removeObserver(self, name: NSPersistentStoreDidImportUbiquitousContentChangesNotification, object: managedObjectContext.persistentStoreCoordinator)
}

但是，有时同步速度太慢。我希望用户通过点击按钮强制同步，或者可能通过向下滑动 tableView 来刷新(重新同步)。我该怎么做？

@IBAction forceSyncButton() {

** 在这里放什么？**

谢谢!

Answer 1

您似乎在使用 Core Data 的内置 iCloud 支持。不幸的是，没有公共(public) API 来强制进行同步。它是自动处理的，您的应用无法更改计划。