nsIObserverService

IID:D07F5192-E3D1-11d2-8ACD-00105A1B8860
Inherits From:nsISupports
Status:FROZEN

Service allows a client listener (nsIObserver) to register and unregister for notifications of specific string referenced topic. Service also provides a way to notify registered listeners and a way to enumerate registered client listeners.

This interface is intended to be used as a service. To create an object implementing this interface:

var obj = Components.classes["@mozilla.org/observer-service;1"].
            getService(Components.interfaces.nsIObserverService);

This interface is implemented by the following components:


Methods

void addObserver ( nsIObserver anObserver , char* topic , PRBool ownsWeak ) nsISimpleEnumerator enumerateObservers ( char* topic ) void notifyObservers ( nsISupports subject , char* topic , PRUnichar* someData ) void removeObserver ( nsIObserver anObserver , char* topic )

void addObserver ( nsIObserver anObserver , char* topic , PRBool ownsWeak )

Registers a given listener for a notifications regarding the specified topic.

Arguments:
anObserver
topic: : The notification topic or subject.
ownsWeak: : If set to false, the nsIObserverService will hold a strong reference to |anObserver|. If set to true and |anObserver| supports the nsIWeakReference interface, a weak reference will be held. Otherwise an error will be returned.

nsISimpleEnumerator enumerateObservers ( char* topic )

Returns an enumeration of all registered listeners.

Arguments:
topic: : The notification topic or subject.

void notifyObservers ( nsISupports subject , char* topic , PRUnichar* someData )

Notifies all registered listeners of the given topic.

Arguments:
subject: : Notification specific interface pointer.
topic: : The notification topic or subject.
someData: : Notification specific wide string.

void removeObserver ( nsIObserver anObserver , char* topic )

Unregisters a given listener from notifications regarding the specified topic.

Arguments:
anObserver: : The interface pointer which will stop recieving notifications.
topic: : The notification topic or subject.

Reference documentation is generated from Mozilla's source.

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