Prev: comp.lang.javascript FAQ - META 2008-04-23
Next: onKeyUp event not firing...or just bad code?
From: vunet on 23 Apr 2008 11:22
If I initializer my object as

var obj = new SomeObject();

then I have some method inside of the object as:

function SomeObject(){
.......
this.showLink = function(){
return "<a href='javascript:void(0)' onClick='obj.showMessage()'></
a>"
}
this.showMessage = function(){ alert("My Message is Here") }
.......
}

Obviously, "onClick='obj.showMessage()' " is a wrong refrence because
we may call it obj2 or have multiple objects. How can I reference any
function of an initialized object on click of a link?
Thank you for suggestions.
From: Thomas 'PointedEars' Lahn on 23 Apr 2008 14:28
vunet wrote:
> If I initializer my object as
>
> var obj = new SomeObject();
>
> then I have some method inside of the object as:
>
> function SomeObject(){
> ......
> this.showLink = function(){
> return "<a href='javascript:void(0)' onClick='obj.showMessage()'></
> a>"
> }
> this.showMessage = function(){ alert("My Message is Here") }
> ......
> }
>
> Obviously, "onClick='obj.showMessage()' " is a wrong refrence because
> we may call it obj2 or have multiple objects. How can I reference any
> function of an initialized object on click of a link?

Don't use strings. And move all methods that don't require a closure to the
prototype object.

function isMethod(o, p)
{
return (o && /\s*(function|object|unknown)\s*/i.test(typeof o[p])
&& o[p]);
}

function SomeObject()
{
this.showLink = function() {
if (isMethod(document, "createElement"))
{
var a = document.createElement("a");

if (a)
{
a.href = "javascript:void(0)";

var me = this;
var f = function(e) {
me.showMessage();

if (isMethod(e, "preventDefault")) e.preventDefault();
if (typeof e.returnValue != "undefined") e.returnValue = false;
return false;
};

if (isMethod(a, "addEventListener"))
{
a.addEventListener("click", f, false);
}
else
{
a.onclick = f;
}
}
}

return a;
};
}

SomeObject.prototype = {
constructor: SomeObject,
showMessage: function(){ alert("My Message is Here") }
};

That said, don't misuse `a' elements like this.

> Thank you for suggestions.

You're welcome.


PointedEars
--
var bugRiddenCrashPronePieceOfJunk = (
navigator.userAgent.indexOf('MSIE 5') != -1
&& navigator.userAgent.indexOf('Mac') != -1
) // Plone, register_function.js:16
 | 
Pages: 1
Prev: comp.lang.javascript FAQ - META 2008-04-23
Next: onKeyUp event not firing...or just bad code?