Extend Kinetc.Shape and all derived shapes

Question

I want to extend the object Kinetic.Shape (from which every other shape extends) with some more properties and methods.

What I tried was

Kinetic.Util.addMethods(Kinetic.Shape, {
  foo: 'bar'
});

So say if I created a new Kinetic.Circle instance, it should contain this defined property ( and every other shape should do so to).

new Kinetic.Circle(options).foo; // returns undefined
// should return 'bar'

How can I achieve this behaviour?

Answer 1

Waiting for merge this pull request https://github.com/ericdrowell/KineticJS/pull/497. Now you can do this - replace Kinetic.Util.extend function with this one:

extend: function(child, parent) {
    function ctor() {
        this.constructor = child;
    }
    ctor.prototype = parent.prototype;
    var old_proto = child.prototype;
    child.prototype = new ctor();
    for (var key in old_proto) {
        if (old_proto.hasOwnProperty(key))
            child.prototype[key] = old_proto[key];
    }
    child.__super__ = parent.prototype;
}