Removing event listeners as Class.prototype functions

You need to bind your function onMyVideoEnded with context where you attached it:

For example:

this.myVideoEndedHandler = this.onMyVideoEnded.bind(this);
this.myVideo.addEventListener("ended", this.myVideoEndedHandler, false);

To remove listener also use stored handler:

this.myVideo.removeEventListener("ended", this.myVideoEndedHandler, false);

This is because when event triggers your function onMyVideoEnded gets wrong this argument.

i use this:

this.element.handler = handler.bind(this);
this.element.removeEventListener('event', this.element.handler, false);
this.element.addEventListener('event', this.element.handler, false);

or use a WeakMap object:

var handlers = new WeakMap();

var self = this;
handlers.set(this.element, { handler: handler.bind(self) });

var handler = handlers.get(this.element).handler;
this.element.removeEventListener('event', handler, false);
this.element.addEventListener('event', handler, false);