good example of OO JS?

Question

Can anyone point me in the right direction of some real world object-orientated javascript? I'm learning OO for javascript from a few books but all the examples given in these books boil down to the dog object inheriting from the animal prototype or similar. I really want to see something a bit more substantial.

I've looked at jQuery and similar libraries (base, prototype) but I consider them to be verbose examples. I was looking for a script where I can see inheritance in use (classical or protoypal) clearly.

Answer 1

Good "real world" examples to learn OO javascript is to actually study some of the javascript frameworks out there. Some of them support and use OO within their own framework code:

• Mootools Core
• YUI
• Prototype class inheritance

These provide great reference and various strategies for writing OO javascript.

Answer 2

IMO, javascript's prototype thingie is very useful, and classic OOP is not necessary.

As a real-world example, consider the google maps v3 api. Let's implement a new OverlayView:

// implement an OverlayView //
MyOverlay.prototype = new google.maps.OverlayView();

// the "constructor" function // function MyOverlay(position, node, map) { // set the parameters // this.position = position; this.node = node; this.map = map; this.setMap(this.map); }

// required onAdd function // MyOverlay.prototype.onAdd = function() { // observe the getPanes function inherited from OverlayView // var panes = this.getPanes(); // bla bla // }

// required draw function // MyOverlay.prototype.draw = function() { // bla bla // } // .. other functions //

// now instantiate an object // var instance = new MyOverlay(position, node, map);

If this doesn't work for you, many external libraries (e.g. Prototype, dojo, jquery, etc) offer great solutions for classic OOP.