ReadyState4

So far it’s been great! Good food, good talks. Here’s the full topic list. (scroll down to the middle of the page)

Took some vids until my camera died, more to come, once I convert ‘em and upload ‘em. Here’s the most interesting things I learned so far:

jQuery:

• jQuery does do DOM caching! It listens for DOM-modified events to clear it’s internal cache.
• That random jquery[random numbers] variable that gets added to the window object is to uniquely identify the jQ instantiation (so you can do things like run multiple instances of jQuery on the same page).
• I knew about .end() but .andSelf()? Cool!
• Nokia and Microsoft join the jQuery camp. Nokia will have jQuery built into their phones (they have some browser-like app environment) $M will have it in their VS/ASP.NET and all future versions of Visual Studio will come with it going foward. link link.
• jQuery is planning to be the first library that doesn’t use any browser sniffing. They are going to use a “quirk check” method of creating some elements that aren’t added to the page that check for things like if white space gets removed when created an element that starts with a space (IE bug) and others. This way they don’t have to be constantly updating for new browsers.
• John’s working on a cool new DOM selector API called Sizzle that’s supposed to be a lot faster. It works by search for the last element in your query up. For example $('div p'); would look for all p elements on the page that has a parent div element.
• You can use create a namespace when binding events. For example $('#foo').bind('click.bar', func); so it’s easy to unbind later, and you can encapsulate your events for your own plugins to prevent conflicts. You can also create your own custom events like $('#foo').bind('apple', func); and trigger them using $('#foo').trigger('apple'); .
• $('#element').data(); lets you bind data to DOM elements (see Data Cache under Internals section here.) Since you can’t really bind an object to a DOM node jQuery assigns it a random key behind the scenes which it references. This is really handly for storing all kinds of data.

jQuery UI:
- Uses the data method above A LOT.
- Lots of enhancements, most interestingly, with drag-and-drop which detects floated elements and allows you to have draggable lists within draggable lists.
- jQuery UI team also working on some experimental stuff for Webkit only (iPhone / Safari / Chrome).
- Theming jQuery UI with ThemeRoller

Other:
- I’ve been using this really old but handy site as a jQ reference: http://visualjquery.com/1.1.2.html made by Yehuda Katz (also a speaker). Asking around on the conference IRC chan I found there’s a much newer / improved one at http://remysharp.com/visual-jquery/ by Remy Sharp. They’re going to try to update the prior site with the latter.
- Canvas tag is pretty basic but sweet. John Resig gave a whole presentation on it since the using jQuery with Firefox plugins couldn’t make it.

It took me about half an hour of Googling to find this, and I couldn’t readily find this in the DWR documentation. Hopefully this may save someone some time:

To make a DWR call synchronous (meaning browser-blocking) you must pass an object as one of the arguments of your DWR call with a property async set to false.

I needed this feature in project where a collection object sends out a call for more data if it didn’t have it:

...
_getData: function(offset, limit){
    var r;
    DWRcomponent.getComments(offset, limit,{ 
        async: false,
        callback: function(s){
            r = toJSON('(' + s + ')');
        }
    });		
    return r;
}
...

Ruby has a cool operator by the name of splat(*) that lets you unpack an array as arguments on the fly. See this code below for an example:

 
# Define the item array
item1 = ['Jack', '39', 'Panda']
 
# Define a regular function that takes three arguments
def hi(name, age, type)
  puts 'Hi ' + name + '! You are ' + age + ' and a ' + type + '!'
end
 
# Call the function using item1 and the splat operator
hi(*item1)
# Outputs: Hi Jack! You are 35 and a Panda!

While JavaScript does not have such a convenient operator, experimenting around, I’ve found a good enough solution:

 
var item1 = ['Jack', '39', 'Panda'];
 
function hi(name, age, type){
     console.log('Hi ' + name + '! You are ' + age + ' and a ' + type + '!');
}
 
hi.apply(this, item1);
// Outputs to your Firebug console: Hi Jack! You are 39 and a Panda!

The apply method is built into all functions in JavaScript and allows you to call a method of an object in the context of a different object (Moz dev page here). Think about it as the equivalent of temporarily moving that method off the current object (the window object if it’s a global function) and attaching it to another object before calling it.

The primary reason to use this method is for changing the this keyword reference inside of the called function, but it has the added benefit of optionally requiring an array of arguments that get passed to the called function. We basically keep the this keyword as the window object (could have specified window instead of this) and use it to unpack our array for us.

This solution is also useful in any situation where you have a function that takes an unlimited number of arguments and you want to to eventually send those arguments to another function that also accepts any number of arguments. This situation is exactly what was puzzling me as I was working on creating a “safe” version of Firebug’s console.log that would work normally in Firefox but alert each argument separately in Internet Explorer.

Lastly, this is usefully for succinct array merging. Instead of looping through one array and pushing each item onto another you can do:

bob = [1,2,3,4];
sue = ['a','b'];
 
bob.push.apply(bob,sue);
bob
// returns [1,2,3,4,a,b]

The problem

I had to find out the language codes of all supported languages in TinyMCE (this page), but unfortunately, they were only listed in the actual download link for each file. A quick sprinkle of jQuery code in my Firebug console would have returned me a list easily but this page didn’t have it – which lead me to consider making a bookmarklet to add jQuery on any page.

The solution:

My wonderful coworker Bryan told me immediately about a simple bookmarklet that does the above called jQuerify. Looking through it, I saw a few potential issues with this script and also decided I wanted something a little more personal, so I came up with my own version:

$jQuerify

Notable differences:

• Moved the jQuery shortcut $ to $j. I always do this on any site I work on because I find $ is used by so many other libraries and scripts that I want to minimize conflicts. Using $j also for sure tells me I’m using jQuery.
• If $ isn’t being used it becomes a shortcut to document.getElementById. I think it’s what people naturally expect $ to do, and in my daily coding I like using $('id'); better than $j('#id')[0]; when all I want to do is return an element.
• Added an initial check for jQuery to prevent running the script unnecessary.

The full source looks like this:

(function(){
    if(!window.jQuery){
        var s=document.createElement('script');
        s.src='http://jquery.com/src/jquery-latest.js';
        document.getElementsByTagName('head')[0].appendChild(s);
 
        var z=setInterval(function(){
            if(window.jQuery){
                $j = jQuery.noConflict();
                alert('jQuery loaded!');
                window.clearInterval(z);
            }
        },100);
    }
    if(!window.$){
	window.$=function(x){return document.getElementById(x);};
    }
})();

$jQuerify <-- Try me out, drag me to your tool bar.

Happy endings

Now I can just hop back over to the TinyMCE Language Pack Download page, run my bookmarklet, type the following in Firebug:

$j('#examplecontent form:first table tbody tr').each(function(c,i){
    var country = $j(this).find('td:eq(2) label').html();
    var code= $j(this).find('td:eq(1) a').attr('href').match(/(?:code=)(..)/)[1];
    console.log(c,country,'=',code);
});

And the list is returned:

0 Arabic = ar
1 Bokmål, Norwegian; Norwegian Bokmål = nb
2 Bosnian = bs
3 Bulgarian = bg
4 Catalan; Valencian = ca
5 Chamorro = ch
6 Chinese = zh
7 Croatian = hr
8 Czech = cs
9 Danish = da
10 Dutch; Flemish = nl
11 English = en
12 Estonian = et
13 Finnish = fi
14 French = fr
15 German = de
16 Greek, Modern (1453-) = el
17 Hebrew = he
18 Hungarian = hu
19 Interlingua (International Auxiliary Language Association) = ia
20 Italian = it
21 Japanese = ja
22 Korean = ko
23 Latvian = lv
24 Lithuanian = lt
25 Macedonian = mk
26 Malay = ms
27 Northern Sami = se
28 Norwegian Nynorsk; Nynorsk, Norwegian = nn
29 Persian = fa
30 Polish = pl
31 Portuguese = pt
32 Romanian = ro
33 Russian = ru
34 Sardinian = sc
35 Serbian = sr
36 Sichuan Yi = ii
37 Sinhala; Sinhalese = si
38 Slovak = sk
39 Slovenian = sl
40 Spanish; Castilian = es
41 Swedish = sv
42 Tatar = tt
43 Turkish = tr
44 Twi = tw
45 Ukrainian = uk
46 Vietnamese = vi

If you haven’t gathered so far, I think the jQuery JavaScript library is the dog’s bollocks. Its small, efficient, and has improved my life as a developer almost as much as Firebug. jQuery gets flack occasionally for containing complex or cryptic code full of ternary operators and multiple variable declarations in a single statement (eg. a=b=1), which I mostly see as concise and efficient coding however, there’s one thing about the jQuery library that I can’t stand. It’s something every developer should do and if you’re not doing it then you’re a jerk and that, ladies and gentlemen, is omitting your curly brackets.

Look at this code snippet from the jQuery library to see what I mean:

for ( ; i < length; i++ )
	// Only deal with non-null/undefined values
	if ( (options = arguments[ i ]) != null )
		// Extend the base object
		for ( var name in options ) {
			var src = target[ name ], copy = options[ name ];
 
			// Prevent never-ending loop
			if ( target === copy )
				continue;
 
			// Recurse if we're merging object values
			if ( deep && copy && typeof copy == "object" && !copy.nodeType )
				target[ name ] = jQuery.extend( deep,
					// Never move original objects, clone them
					src || ( copy.length != null ? [ ] : { } )
				, copy );
 
			// Don't bring in undefined values
			else if ( copy !== undefined )
				target[ name ] = copy;
 
		}
 
// Return the modified object
return target;

Coding in this way leads is extremely error-prone especially for open-souce projects where many others are modifying your code. Please stop it.

Love,

A dedicated user