A listener may well be an implementation of the observer pattern . A listener is essentially waiting for an event to occur on a given object, which is what an observer does.
Read moreWhat are observers in code?
The observer pattern is a software design pattern in which an object, named the subject, maintains a list of its dependents , called observers, and notifies them automatically of any state changes, usually by calling one of their methods.
Read moreAre listeners observers?
The object which is being watched is called the subject. The objects which are watching the state changes are called observers or listeners .
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