Interface for raising a detailed event containing the change notification about what has changed in the element. CommandifiedList picks up these events and bubbles upwards this event to subscribers.

Simple interface which is used by elements which require support from external code to get their internal observer logic be setup. This is required sometimes in undo-redo scenarios where an element is added/removed from a datastructure, e.g. a list.

Simple notification interface which is used to signal elements which refer to other elements that the implementing element has been changed. The type/nature of the change isn't available, as other channels are meant for that, this notification is a simple 'I'm changed' kind of notification used by CommandifiedMember.

Simple notification interface which is used to signal elements which refer to other elements that the implementing element has been removed.