xpcom/ds/nsIObserver.idl

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "nsISupports.idl"
   7
   8 /**
   9  * This interface is implemented by an object that wants
  10  * to observe an event corresponding to a topic.
  11  */
  12
  13 [scriptable, function, uuid(DB242E01-E4D9-11d2-9DDE-000064657374)]
  14 interface nsIObserver : nsISupports {
  15
  16    /**
  17     * Observe will be called when there is a notification for the
  18     * topic |aTopic|.  This assumes that the object implementing
  19     * this interface has been registered with an observer service
  20     * such as the nsIObserverService.
  21     *
  22     * If you expect multiple topics/subjects, the impl is
  23     * responsible for filtering.
  24     *
  25     * You should not modify, add, remove, or enumerate
  26     * notifications in the implemention of observe.
  27     *
  28     * @param aSubject : Notification specific interface pointer.
  29     * @param aTopic   : The notification topic or subject.
  30     * @param aData    : Notification specific wide string.
  31     *                    subject event.
  32     */
  33     void observe( in nsISupports aSubject,
  34                   in string      aTopic,
  35                   in wstring     aData );
  36
  37 };