NSPersistentStoreCoordinator.StoresWillChangeNotification Property


Notification constant for StoresWillChange

[Foundation.Advice("Use NSPersistentStoreCoordinator.Notifications.ObserveStoresWillChange helper method instead.")]
[Foundation.Field("NSPersistentStoreCoordinatorStoresWillChangeNotification", "CoreData")]
[ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 7, 0, ObjCRuntime.PlatformArchitecture.All, null)]
[ObjCRuntime.Introduced(ObjCRuntime.PlatformName.MacOSX, 10, 9, ObjCRuntime.PlatformArchitecture.All, null)]
[get: ObjCRuntime.Introduced(ObjCRuntime.PlatformName.iOS, 7, 0, ObjCRuntime.PlatformArchitecture.All, null)]
[get: ObjCRuntime.Introduced(ObjCRuntime.PlatformName.MacOSX, 10, 9, ObjCRuntime.PlatformArchitecture.All, null)]
public static Foundation.NSString StoresWillChangeNotification { get; }
member this.StoresWillChangeNotification : Foundation.NSString

Property Value


NSString constant, should be used as a token to NSNotificationCenter.



This constant can be used with the NSNotificationCenter to register a listener for this notification. This is an NSString instead of a string, because these values can be used as tokens in some native libraries instead of being used purely for their actual string content. The 'notification' parameter to the callback contains extra information that is specific to the notification type.

To subscribe to this notification, developers can use the convenience NSPersistentStoreCoordinator.Notifications.ObserveStoresWillChange method which offers strongly typed access to the parameters of the notification.

The following example shows how to use the strongly typed Notifications class, to take the guesswork out of the available properties in the notification:

// Lambda style

// listening notification = NSPersistentStoreCoordinator.Notifications.ObserveStoresWillChange ((sender, args) => { /* Access strongly typed args */ Console.WriteLine ("Notification: {0}", args.Notification);

Console.WriteLine ("EventType", args.EventType);


// To stop listening: notification.Dispose ();

// // Method style // NSObject notification; void Callback (object sender, CoreData.NSPersistentStoreCoordinatorStoreChangeEventArgs args) { // Access strongly typed args Console.WriteLine ("Notification: {0}", args.Notification);

Console.WriteLine ("EventType", args.EventType);


void Setup () { notification = NSPersistentStoreCoordinator.Notifications.ObserveStoresWillChange (Callback); }

void Teardown () { notification.Dispose (); }

The following example shows how to use the notification with the DefaultCenter API:

// Lambda style
NSNotificationCenter.DefaultCenter.AddObserver (
        NSPersistentStoreCoordinator.StoresWillChangeNotification, (notification) => {Console.WriteLine ("Received the notification NSPersistentStoreCoordinator", notification); }

// Method style void Callback (NSNotification notification) { Console.WriteLine ("Received a notification NSPersistentStoreCoordinator", notification); }

void Setup () { NSNotificationCenter.DefaultCenter.AddObserver (NSPersistentStoreCoordinator.StoresWillChangeNotification, Callback); }

Applies to