jQuery UI Widget Factory Live Binding

I recently developed my first jQuery UI Custom Widget using the jQuery UI Widget Factory. I found the Widget Factory to be a nice framework for what I needed to do and took away a bit of the complexity normally needed for a UI plugin.

It did introduce a level of complexity for live event binding. For example, I want all dynamically generated anchor tags to run a method when clicked.

The Widget Factory wants us to use the “this._on” method to accomplish this. The Widget Factory is a little undocumented so it was hard to figure this one out.

At first I tried the following:

$.widget( "CFWT.myWidget", {

	_create: function() {
		this._on('.myClass', {
			click: function(event) {
				var $container = $(event.target);
				doSomething($container);
			}
		});
	}
	
	_doSomething: function(container) {
		console.log(container);
	}

});

However I quickly found out that the event was only bound with any classes created the first time. After some Q&A on Stack Overflow I finally figured out the correct way.

$.widget( "CFWT.myWidget", {

	_create: function() {
		this._on(this.element, {
			'click.myClass': function(event) {
				var $container = $(event.target);
				this._doSomething($container);
			}
		});
	}
	
	_doSomething: function($container) {
		console.log($container);
	}

});

This new code will bind any “myClass” class that is created inside the widget’s container. If you want it document wide then replace “this.element” with “document” or another container.

You may also notice that I use “$(event.target)” instead of “this”. That is because “this” doesn’t change to the event. Instead, I believe, it remains at the widget level, which can be pretty confusing.

A working example can be found at http://jsfiddle.net/vEAhq/8/

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#bind, #event, #jquery, #live, #ui, #widget

jQuery Issue With Multiple Selectors and clone()/appendTo()

On a current project, the website was and many interactive jQuery “modules” where supplied by a 3rd party designer. We I pieced it together with ColdFusion everything worked great on IE8+, FF and Chrome. However it was soon discovered that a large customer of the client couldn’t upgrade past IE7 at the moment. After running the JavaScript through jsLint, that fixed the majority of the issues. Heck, just a couple of commas out of place will make a nightmare out of IE7.

However there was an issue that took me a whole day to figure out. (We’re talking thousands of lines of code to debug with no error being thrown).

As a general description, the site is a customized e-commerce site in its basic functionality. It has a category navigation tree to the left, with a product result grid to the right. When an item on the grid is clicked, the grid is hidden and replaced by a product detail section populated via AJAX.

First of all, there where around 1,500 categories that where populated into the DOM on page load via an un-ordered list. It was then converted into a cascading tree. The way you’re supposed to do it for accessibility and SEO purposes right? Well, IE7 didn’t take too kindly to that and took about a whole minute to display. IE8+ took probably around a second.

To resolve this issue I created a jQuery UI Widget via the Widget Factory. This required upgrading the version of jQuery being used, and I chose the latest one at 1.9.1 that still supported IE7.

After the tree was created and implemented, it became clear that only one product in the product grid was showing as opposed to the 15 for each page.

I determined that jQuery 1.7.2 loaded the grid as expected, but both 1.8 and 1.9 versions only loaded one. The method used to populate the grid was to clone a hidden div, populate it, append it to the parent container and make it visible using data from an AJAX JSON data set. It was looped via an $.each() method.

Because there where no errors being thrown, and I needed that newer version of jQuery I started the process of elimination. That process took me to the bitter end. I found that I couldn’t use multiple elements inside a selector. For example:

$('#myDIV1,#myDIV2').hide();

The above would inhibit all but one cloned container to be displayed. The workaround was to split up the selectors:

$('#myDIV2').hide();
$('#myDIV2').hide();

This would only happen in IE7. IE8+, FF, and Chrome worked just fine. It also only happened in jQuery 1.8+.

I could reproduce this any time, ripping out most of the app down to the essentials.

However at this time, creating a basic app in another virtual site works just fine. I may try to figure it out at a later time, but right now I can’t duplicate the issue.

But I’m writing this in case anyone runs into this edge case and needs a workaround. Hopefully I can find the cause and submit a bug to the jQuery team.

#appendto, #clone, #ie7, #internet-explorer, #jquery, #ui

jQuery UI Dialog Centering Issue

I’m working with some code that’s been worked over many, many times over the years. It could a thorough scrubbing, but that’s not in the scope of my request.

I just upgraded the jQuery UI to version 1.9.2 and jQuery to 1.8.3 and added a simple dialog.

test_dialogIt was expected that the dialog would center itself to the browser window. However it appeared to be centering itself to the html element and scrolling the page to make it centered if the content was longer than the window height.

Here’s the code:

<html>
<head>
    <title>My Title</title>
</head>
<body>
    <div id="userNoticeDialog" style="display: none;" title="Notice">
        test content
    </div>

    <script type="text/javascript">
        $("#userNoticeDialog").dialog();
    </script>
</body>
</html>

After a process of elimination and seeing that there was no doctype declared, I tried adding a doctype. That resolved the issue.

<!DOCTYPE html>
<html>
<head>
    <title>My Title</title>
</head>
<body>
    <div id="userNoticeDialog" style="display: none;" title="Notice">
        test content
    </div>

    <script type="text/javascript">
        $("#userNoticeDialog").dialog();
    </script>
</body>
</html>

I believe the reason was the lack of a DOCTYPE caused the (Chrome) browser to go into quirks mode, while the inclusion of the DOCTYPE caused the (Chrome) browser to go into standards mode. However, I’m not sure how to detect which mode the Chrome browser is currently in. Does anyone know?

#center, #dialog, #doctype, #html, #jquery, #ui