CFNotificationCenter.AddObserver Method
Definition
Important
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Adds an observer to the notification center.
public CoreFoundation.CFNotificationObserverToken AddObserver (string name, ObjCRuntime.INativeObject objectToObserve, Action<string,Foundation.NSDictionary> notificationHandler, CoreFoundation.CFNotificationSuspensionBehavior suspensionBehavior = CoreFoundation.CFNotificationSuspensionBehavior.DeliverImmediately);
member this.AddObserver : string * ObjCRuntime.INativeObject * Action<string, Foundation.NSDictionary> * CoreFoundation.CFNotificationSuspensionBehavior -> CoreFoundation.CFNotificationObserverToken
Parameters
- name
- String
Name of the notification to observer, or null
if you want the notificationHandler to be invoked for all notifications posted. null
is not allowed for the Darwin notification center.
- objectToObserve
- INativeObject
For non-Darwin notification centers, the object to observe. If null
is passed, then the notificationHandler is invoked for all objects that have a notification named name posted.
- notificationHandler
- Action<String,NSDictionary>
Handler to invoke when a notification is posted.
- suspensionBehavior
- CFNotificationSuspensionBehavior
Determines how a notification is processed when the application is in the background.
Returns
Token representing the notification, use this token if you want to later remove this observer.
Remarks
Registers a method to be invoked when a notification is posted to a specific object.
The handler is invoked on the same thread that posted the message, or from the loop that pumped the notification. If your code needs to run in a specific thread, you should take care of that in your handler.
Use the returned value as a token to RemoveObserver(CFNotificationObserverToken) if you want to stop getting notifications.