Nilesh wrote:
about exact fnctionality serverd by a listener(nsieventlistenermanager
Event listeners listen for DOM events. These are fired within the web
page by either the page itself or Mozilla. They are typically targeted
at a particular node. Things like onclick, onfocus, onblur, etc fall in
this category.
) and an observer ( e.g.profilechangeobserver ) .
Observers will typically register with the observer service or in some
cases with some other mozilla-internal thing to be notified of when
things happen. The notifications are almost never associated with a
particular page and are all generated internally by Mozilla. Things
like "application shutting down", "profile changed", "not much free RAM
left" are typical observer notifications
