Javascript scope problem with object and setTimeout

Posted by Shabbyrobe on Stack Overflow See other posts from Stack Overflow or by Shabbyrobe
Published on 2010-05-11T13:56:05Z Indexed on 2010/05/11 14:44 UTC
Read the original article Hit count: 256

Filed under:

I'm trying to make a jQuery plugin that executes a method on a timer. I'd like it to work on multiple elements on a page independently. I've reached a point where the timer executes for each element, but the method called in the setTimeout seems to only know about the last instance of the plugin.

I know I'm doing something fundamentally stupid here, but I'm danged if I know what. I know stuff like this has been asked 8 million times on here before, but I've not managed to find an answer that relates to my specific problem.

Here's a script that demonstrates the structure of what I'm doing.

<html>
<head>
<script type="text/javascript" src="assets/jquery.min.js"></script>
<script type="text/javascript">
var crap = 0;
(function($) 
{
    jQuery.fn.pants = function(options) {
        var trousers = {
            id: null,
            current: 0,
            waitTimeMs: 1000,

            begin: function() {
                var d = new Date();
                this.id = crap++;
                console.log(this.id);
                // do a bunch of stuff
                window.setTimeout(function(self) {return function() {self.next();}}(this), this.waitTimeMs);
            },

            next: function() {
                this.current ++;
                console.log(this.id);
                window.setTimeout(function(self) {return function() {self.next();}}(this), this.waitTimeMs);
            },
        };

        options = options || {};
        $.extend(trousers, options);

        this.each(function(index, element) {
            trousers.begin();
        });

        return this;
    };
}
)(jQuery);
jQuery(document).ready(function() {
    jQuery("div.wahey").pants();
});
</script>
</head>
<body>
<div class="wahey"></div>
<div class="wahey"></div>
</body>
</html>

The output I get is this:

0
1
1
1
1
1

The output I expect to get is this:

0
1
0
1
0
1

© Stack Overflow or respective owner

Related posts about jQuery