Question

I have some javascript code (within an object) :

toggle: function() {
    var me = this;
    var handler = function() { me.progress() };
    me.intervalId = setInterval(handler, me.intervalTime);
    //...More code
}

I’m kind of new to javascript, so doing the above as far as I can tell actually passes the me variable into anonymous the function. I was wanting to see if there is a more declarative way to do so? I wanted something along the line of:

var handler = (function(o) { o.progress();})(this));

but that doesn’t seem to be working… Am I missing something? Is this a case where “this is the way the language works so just declare a local variable and deal with it”?

UPDATE:

The source to my problem was/is my unclear understanding of scope and closures in javascript. I found this article to help me understand a little more.

Answer 1

You can use “.bind()”:

var handler = function() { this.progress(); }.bind(this);

New browsers have “bind()”, and the Mozilla docs have a solid implementation you can use to patch older browsers.