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Events

A simple event system, mostly created to support Plugins. Allows you to hook into Kontra lifecycle events or create your own.

import { on, off, emit } from 'kontra';

function callback(a, b, c) {
  console.log({a, b, c});
});

on('myEvent', callback);
emit('myEvent', 1, 2, 3);  //=> {a: 1, b: 2, c: 3}
off('myEvent', callback);

Table of Contents

Lifecycle Events

There are currently only two lifecycle events:

  • init - Emitted after init() is called.
  • tick - Emitted every frame of GameLoop before the loops update() and render() functions are called.

emit(event, args)

Call all callback functions for the event. All arguments will be passed to the callback functions.

Parameters

event

String. Name of the event.

args

Any type. Arguments passed to all callbacks.

off(event, callback)

Remove a callback for an event.

Parameters

event

String. Name of the event.

callback

Function. The function that was passed during registration.

on(event, callback)

Register a callback for an event to be called whenever the event is emitted. The callback will be passed all arguments used in the emit call.

Parameters

event

String. Name of the event.

callback

Function. Function that will be called when the event is emitted.