Patrón Observer Java

The EventListener interface represents an object that can handle an event dispatched by an EventTarget object. Note: Due to the need for compatibility with legacy content, EventListener accepts both a function and an object with a handleEvent() property function. This is shown in the example below.

An event listener is a procedure in JavaScript that waits for an event to occur . The simple example of an event is a user clicking the mouse or pressing a key on the keyboard.

Note: Event handlers are sometimes called event listeners — they are pretty much interchangeable for our purposes, although strictly speaking, they work together. The listener listens out for the event happening , and the handler is the code that is run in response to it happening.