Javascript inheritance misbehaviour

I have some js code here link deleted

If you open your js console and you'll run this code snipet

var r = new TempPopupForm("xxx");
r.create();

an error will appear

TypeError: this.init is not a function

this error is saying there is no init method implemented on this object.

But that's not true.As you can see in the code below the init method is declared.

TempPopupForm.prototype = new PopupForm();
TempPopupForm.prototype.constructor = TempPopupForm;
TempPopupForm.superclass = PopupForm.prototype;

function TempPopupForm(name) {
     this.init(name);
}
TempPopupForm.prototype.init = function(name) {
     TempPopupForm.superclass.init.call(this, name);
};

I guess something is wrong with the inheritance definition,but I can not figure out what it is.

BTW There are some third party dependencies.

EDIT

I was following this article and where the funcs are ordered like I have. The order actually works on the other classes, but not on this one. http://www.kevlindev.com/tutorials/javascript/inheritance/inheritance10.htm

Copyright Notice：Content Author:「user49126」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/7822112/javascript-inheritance-misbehaviour