nsIAnnotationObserver
1.0 66 introduced gecko 1.8 inherits from: nsisupports last changed in gecko 1.9 (firefox 3) method overview void onitemannotationremoved(in long long aitemid, in autf8string aname); void onitemannotationset(in long long aitemid, in autf8string aname); void onpageannotationremoved(in nsiuri auri, in autf8string aname); void onpageannotationset(in nsiuri apage, in autf8string aname); methods onitemannotationremoved() this method is called when an annotation is deleted for an item.
...void onitemannotationremoved( in long long aitemid, in autf8string aname ); parameters aitemid the item whose annotation is to be deleted.
... onpageannotationremoved() called when an annotation is deleted for a uri.
...void onpageannotationremoved( in nsiuri auri, in autf8string aname ); parameters auri the uri whose annotation is to be deleted.

Using the Places annotation service
the objects must implement four methods, which are called when an annotation is set/removed on a uri or item respectively: onpageannotationset(auri, aname); onitemannotationset(aitemid, aname); onpageannotationremoved(auri, aname); onitemannotationremoved(aitemid, aname); var observer = { onpageannotationset : function(auri, aname) { }, onitemannotationset : function(aitemid, aname) { }, onpageannotationremoved : function(auri, aname) { }, onitemannotationremoved: function(aitemid, aname) { } } annotationservice.addobserver(observer); } ...