This event basically is equivalent to the calculateNumberOfPages event.
It does, however, provide a less ambiguous place for additional SQL
conditions added by plugins: Pages that extend MultipleLinkPage add
their conditions in initObjectList, plugins can use afterInitObjectList
instead of calculateNumberOfPages for clarity.
// initialize database object list
$this->initObjectList();
+ EventHandler::getInstance()->fireAction($this, 'afterInitObjectList');
+
// calculates page number
$this->calculateNumberOfPages();