NSNotificationCenter.AddObserver Method

Definition

Namespace:: Foundation

Assembly:: Microsoft.iOS.dll

Assembly:: Microsoft.MacCatalyst.dll

Assembly:: Microsoft.macOS.dll

Assembly:: Microsoft.tvOS.dll

Important

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Overloads

Name	Description
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)
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.NSObject

Parameters

aName: NSString

The name of the notification to observe.

notify: Action<NSNotification>

The delegate that will be invoked when the notification is posted.

Returns

NSObject

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.NSObject

Parameters

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

NSObject

An observer token that can be used later as the parameter passed to RemoveObserver (NSObject observer).

Applies to

AddObserver(NSObject, Selector, NSString, NSObject)

[Foundation.Export("addObserver:selector:name:object:")]
[ObjCRuntime.BindingImpl(ObjCRuntime.BindingImplOptions.GeneratedCode | ObjCRuntime.BindingImplOptions.Optimizable)]
public virtual void AddObserver(Foundation.NSObject observer, ObjCRuntime.Selector aSelector, Foundation.NSString? aName, Foundation.NSObject? anObject);

[<Foundation.Export("addObserver:selector:name:object:")>]
[<ObjCRuntime.BindingImpl(ObjCRuntime.BindingImplOptions.GeneratedCode | ObjCRuntime.BindingImplOptions.Optimizable)>]
override this.AddObserver : Foundation.NSObject * ObjCRuntime.Selector * Foundation.NSString * Foundation.NSObject -> unit

Parameters

observer: NSObject

aSelector: Selector

aName: NSString

anObject: NSObject

Attributes: ExportAttribute BindingImplAttribute

Applies to

AddObserver(String, NSObject, NSOperationQueue, Action<NSNotification>)

[Foundation.Export("addObserverForName:object:queue:usingBlock:")]
[ObjCRuntime.BindingImpl(ObjCRuntime.BindingImplOptions.GeneratedCode | ObjCRuntime.BindingImplOptions.Optimizable)]
public virtual Foundation.NSObject AddObserver(string? name, Foundation.NSObject? obj, Foundation.NSOperationQueue? queue, Action<Foundation.NSNotification> handler);

[<Foundation.Export("addObserverForName:object:queue:usingBlock:")>]
[<ObjCRuntime.BindingImpl(ObjCRuntime.BindingImplOptions.GeneratedCode | ObjCRuntime.BindingImplOptions.Optimizable)>]
override this.AddObserver : string * Foundation.NSObject * Foundation.NSOperationQueue * Action<Foundation.NSNotification> -> Foundation.NSObject