NSNotificationCenter.AddObserver Method
Definition
Important
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Overloads
| AddObserver(NSString, Action<NSNotification>) |
Adds an observer for the specified notification |
| AddObserver(NSString, Action<NSNotification>, NSObject) |
Adds an observer for the specified notification |
| AddObserver(NSObject, Selector, NSString, NSObject) |
Low-level add-observer API |
| AddObserver(String, NSObject, NSOperationQueue, Action<NSNotification>) |
AddObserver(NSString, Action<NSNotification>)
Adds an observer for the specified notification
public Foundation.NSObject AddObserver (Foundation.NSString aName, Action<Foundation.NSNotification> notify);override this.AddObserver : Foundation.NSString * Action<Foundation.NSNotification> -> Foundation.NSObjectParameters
- aName
- NSString
The name of the notification to observe.
- notify
- Action<NSNotification>
The delegate that will be invoked when the notification is posted.
Returns
An observer token that can be used later as the parameter passed to RemoveObserver (NSObject observer).
Applies to
AddObserver(NSString, Action<NSNotification>, NSObject)
Adds an observer for the specified notification
public Foundation.NSObject AddObserver (Foundation.NSString aName, Action<Foundation.NSNotification> notify, Foundation.NSObject fromObject);override this.AddObserver : Foundation.NSString * Action<Foundation.NSNotification> * Foundation.NSObject -> Foundation.NSObjectParameters
- aName
- NSString
The name of the notification to observe.
- notify
- Action<NSNotification>
The delegate that will be invoked when the notification is posted.
- fromObject
- NSObject
If not-null, filters the notifications to those sent by this object.
Returns
An observer token that can be used later as the parameter passed to RemoveObserver (NSObject observer).
Applies to
AddObserver(NSObject, Selector, NSString, NSObject)
Low-level add-observer API
[Foundation.Export("addObserver:selector:name:object:")]
public virtual void AddObserver (Foundation.NSObject observer, ObjCRuntime.Selector aSelector, Foundation.NSString aName, Foundation.NSObject anObject);override this.AddObserver : Foundation.NSObject * ObjCRuntime.Selector * Foundation.NSString * Foundation.NSObject -> unitParameters
- observer
- NSObject
- aSelector
- Selector
- aName
- NSString
Optional name that you want to register with and filter delivery by this name. Use null if you do not want filtering to take place.
This parameter can be null.
- anObject
- NSObject
The object that we want to receive notifications from, or null for receiving the specified notifications sent by all objects.
This parameter can be null.
- Attributes
Remarks
This is a low-level version of the AddObserver API that allows the consumer to control the observer and the selector to notify upon notifications.
Developers are encouraged to use the high-level AddObserver(NSString, Action<NSNotification>, NSObject) variant.
Applies to
AddObserver(String, NSObject, NSOperationQueue, Action<NSNotification>)
[Foundation.Export("addObserverForName:object:queue:usingBlock:")]
public virtual Foundation.NSObject AddObserver (string name, Foundation.NSObject obj, Foundation.NSOperationQueue queue, Action<Foundation.NSNotification> handler);override this.AddObserver : string * Foundation.NSObject * Foundation.NSOperationQueue * Action<Foundation.NSNotification> -> Foundation.NSObjectParameters
- handler
- Action<NSNotification>
Returns
- Attributes