Joomla! Documentation™

Joomla! Observer Implementation

Joomla! implements the Observer pattern at a global level through the JPlugin (Observer) and JEventDispatcher (Observable) classes. Anyone wanting to receive notification of events will create a Plugin that extends the JPlugin class. Subclasses of JPlugin will automatically register themselves to the global JEventDispatcher class when their Plugin category has been loaded (more on that later). The JEventDispatcher class is used as a dispatching mechanism that receives events from the communicators and forwards them to the listeners that have been loaded. For a full explanation of this read the Plugin Developer Overview