EventDispatcher

A JavaScript event dispatcher which supports bubbling and capture phases, and bubbling up the DOM tree.

This library is intended to be used with NPM / ES6 projects.

Installation

I recommend installing this library via NPM

npm install @perry-rylance/event-dispatcher

Usage

Any class which extends EventDispatcher can use the following methods

• addEventListener / on
• removeEventListener / off
• dispatchEvent / trigger / emit
• hasEventListener

Bubbling

When an object emits an event, the event dispatcher will look for a parent property on the object.

The dispatcher will then traverse up the ancestors of the object this way, until no more parent is found.

In the absense of a parent, if the dispatcher finds a property named element, then a DOM event will be dispatched on the element via jQuery (please note that jQuery is required to drive this behaviour). This is useful for events emitted from an object with no DOM representation, such as a sprite on a canvas, which you may wish to listen for on the DOM tree - for instance a click event on your sprite.

When an event bubbles up to the DOM, a namespace suffix is added, for instance click.ed. The default suffix is ed. You can change this by altering EventDispatcher.domNamespaceSuffix, or by passing the domNamespaceSuffix in the constructor options for individual event dispatchers, if you so wish.