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Polygons reloaded

In this case, the superclass

init()

method is being called first, which is required for xbObjects to work.

Even though

ClassA

didn’t register a superclass, a default superclass for all classes is created using

xbObjects, which is where this superclass

init()

method comes from.

The fourth and final step is to add the other class methods inside of the prototype function:

_classes.registerClass(“ClassA”);

function ClassA(sColor) {

_classes.defineClass(“ClassA”, prototypeFunction);

this.init(sColor);

function prototypeFunction() {

ClassA.prototype.init = function (sColor) {

this.parentMethod(“init”);

this.color = sColor;

};

ClassA.prototype.sayColor = function () {

alert(this.color);

};

}

Then, you can create an instance of

ClassA

in the normal way:

var objA = new ClassA(“red”);

objA.sayColor(); //outputs “red”

Polygons reloaded

At this point, surely you’re wondering if you will have a chance to see the polygon example redone

using xbObjects, so here it goes.

First, rewrite the

Polygon

class, which is very simple:

_classes.registerClass(“Polygon”);

function Polygon(sides) {

_classes.defineClass(“Polygon”, prototypeFunction);

this.init(sides);

function prototypeFunction() {

Polygon.prototype.init = function(iSides) {

this.parentMethod(“init”);

this.sides = iSides;

};

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