Fetching latest commit…
Cannot retrieve the latest commit at this time.
Failed to load latest commit information.

MooTools TrackInstances Class Mutator

Creates an instances array property for a class, to contain all of its instances. The array can be used to alter all instances at once, for example -

  • A widget class that its instances need to be repositioned upon a window resize
  • Stop all music players at once
  • Hide all instances of a popup class at once

How to use

Just add TrackInstances:true to your class definition, after the initialize method.

var MyClass=new Class({
    initialize:function () {


    recalcPosition:function () {
        // something that recalculates position or any other task that should be applied on an instance

var x=new MyClass();
var y=new MyClass();

MyClass.instances; // [x, y]
MyClass.instances.length; // 2

// from another code:
window.addEvent("resize",function () {
    MyClass.instances.each(function (instance) {

Full post

Elad Ossadon's Blog