xpcom/ds/nsIObserverService.idl

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  37
  38 #include "nsISupports.idl"
  39
  40 interface nsIObserver;
  41 interface nsISimpleEnumerator;
  42
  43 /**
  44  * nsIObserverService
  45  *
  46  * Service allows a client listener (nsIObserver) to register and unregister for
  47  * notifications of specific string referenced topic. Service also provides a
  48  * way to notify registered listeners and a way to enumerate registered client
  49  * listeners.
  50  */
  51
  52 [scriptable, uuid(D07F5192-E3D1-11d2-8ACD-00105A1B8860)]
  53 interface nsIObserverService : nsISupports
  54 {
  55
  56     /**
  57      * AddObserver
  58      *
  59      * Registers a given listener for a notifications regarding the specified
  60      * topic.
  61      *
  62      * @param anObserve : The interface pointer which will receive notifications.
  63      * @param aTopic    : The notification topic or subject.
  64      * @param ownsWeak  : If set to false, the nsIObserverService will hold a
  65      *                    strong reference to |anObserver|.  If set to true and
  66      *                    |anObserver| supports the nsIWeakReference interface,
  67      *                    a weak reference will be held.  Otherwise an error will be
  68      *                    returned.
  69      */
  70         void addObserver( in nsIObserver anObserver, in string aTopic, in boolean ownsWeak);
  71
  72     /**
  73      * removeObserver
  74      *
  75      * Unregisters a given listener from notifications regarding the specified
  76      * topic.
  77      *
  78      * @param anObserver : The interface pointer which will stop recieving
  79      *                     notifications.
  80      * @param aTopic     : The notification topic or subject.
  81      */
  82     void removeObserver( in nsIObserver anObserver, in string aTopic );
  83
  84     /**
  85      * notifyObservers
  86      *
  87      * Notifies all registered listeners of the given topic.
  88      *
  89      * @param aSubject : Notification specific interface pointer.
  90      * @param aTopic   : The notification topic or subject.
  91      * @param someData : Notification specific wide string.
  92      */
  93     void notifyObservers( in nsISupports aSubject,
  94                           in string aTopic,
  95                           in wstring someData );
  96
  97     /**
  98      * enumerateObservers
  99      *
 100      * Returns an enumeration of all registered listeners.
 101      *
 102      * @param aTopic   : The notification topic or subject.
 103      */
 104         nsISimpleEnumerator enumerateObservers( in string aTopic );
 105
 106
 107 };
 108
 109