yui on the go

YUI on the goHow to include YUI components on demand

Christian HeilmannYahoo! Frontend Engineering Summit UK

December 2007

Why use libraries?

Use goodlibrary

Plan Code

Job done

Without libraries:

Browser HellPlan Code

OS inconsistenciesForget about obscure bugs

Cannot reproduce

> CVS commit> Conflict: > Too much fail error.

You.sacked = true

MCSE

“You want fries with that?”

Ergo:Libraries are good, mkay?

A common complaint.

“YUI is too big! If I want to build something on top of it, I need to include a lot of large

files!”

yahoo.js – 4.6kbdom.js – 35kbevent.js – 61kb

reset.css – 0.5kbfonts.css – 0.6kbgrids.css – 3kb

6 HTTP requests – 104.7kb

First Aid remedies:

– Use the minified YUI versions

yahoo-min.js – 1kbdom-min.js – 10.2kbevent-min.js – 13kb

reset-min.css – 0.4kbfonts-min.css – 0.2kbgrids-min.css – 2.4kb

6 HTTP requests – 27.2kb

First Aid remedies:

– Use the minified YUI versions – Cut down on included YUI

components by using the combined component includes.

yahoo-dom-event.js – 24.1kbreset-fonts-grids.css – 3.1kb

2 HTTP requests – 27.2kb

First Aid remedies:

– Use the minified YUI versions – Cut down on included YUI

components by using the combined component includes.

– Use the hosted YUI versions.

This is all packing and level crunching.

What we really want is...

On-demand delivery

Why is that needed?

Use cases:

Use cases:

– We don’t want to make users load things they don’t need.

Use cases:

– We don’t want to make users load things they don’t need.

– Distribution (badges, banners) works a lot better if it is one <script> and not 3.

Use cases:

– We don’t want to make users load things they don’t need.

– Distribution (badges, banners) works a lot better if it is one <script> and not 3.

– We can offer implementers to trigger extra functionality with markup:

Use cases:

– We don’t want to make users load things they don’t need.

– Distribution (badges, banners) works a lot better if it is one <script> and not 3.

– We can offer implementers to trigger extra functionality with markup:

“add an ‘animated’ CSS class for smooth transitions”

Example?

<div class="flickrbadge"> <p><a

href="http://www.flickr.com/photos/11414938%40N00">

My latest photos on flickr</a>

</p> </div> <script src="flickrbadgeloader.js"></script>

http://icant.co.uk/sandbox/flickrbadgev2/

<div class="flickrbadge"> <p><a

href="http://www.flickr.com/photos/11414938%40N00">

My latest photos on flickr</a>

</p> </div> <script src="flickrbadgeloader.js"></script>

http://icant.co.uk/sandbox/flickrbadgev2/

<div class="flickrbadge"> <p><a

href="http://www.flickr.com/photos/11414938%40N00">

My latest photos on flickr</a>

</p> </div> <script src="flickrbadgeloader.js"></script>

http://icant.co.uk/sandbox/flickrbadgev2/

How?

Supercool Solution:

The YUI Loader

http://developer.yahoo.com/yui/yuiloader

YUI Loader:

YUI Loader:

– Knows about dependencies

YUI Loader:

– Knows about dependencies – Automatically gets the newest

hosted versions

YUI Loader:

– Knows about dependencies – Automatically gets the newest

hosted versions– Works without yahoo.js

YUI Loader:

– Knows about dependencies – Automatically gets the newest

hosted versions– Works without yahoo.js– Extendable with non-YUI

components(!)

<script src="http://yui.yahooapis.com/2.3.1/build/yuiloader/yuiloader-beta-min.js"></script>

<script>loader = new YAHOO.util.YUILoader();loader.require('calendar','tabview');loader.insert(function() {

// Your code});</script>

http://yuiblog.com/assets/pdf/cheatsheets/yuiloader.pdf

Other option – 11kb is too much!

Rolling your own

The YAHOO_config way

YUI has an often forgotten configuration setting in

YAHOO_config.

YUI has an often forgotten configuration setting in

YAHOO_config.

http://developer.yahoo.com/yui/yahoo/#config

YUI has an often forgotten configuration setting in

YAHOO_config.

http://developer.yahoo.com/yui/yahoo/#configNow with more AWESOME!

It allows you to define a listener function that gets notified every time a YUI

component is loaded.

<script>function snitch(component){

console.log('can has YUI ' + component.name);

};YAHOO_config = {

listener:snitch};</script><script src="http://yui.yahooapis.com/2.3.1/build/yahoo/yahoo-min.js"></script><script src="http://yui.yahooapis.com/2.3.1/build/event/event-min.js"></script>

Using this in conjunction with your scripts and repeat calls

of the “snitch” function allows you to dynamically

include the YUI.

var myScript = function(){// other code function addScript(url){

var s = document.createElement('script');s.setAttribute('type', 'text/javascript');s.setAttribute('src', url);document.getElementsByTagName('head')[0].appendChild(s);

};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {

if(o.name === 'yahoo-dom-event'){ // YUI is ready}

};};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code function addScript(url){

var s = document.createElement('script');s.setAttribute('type', 'text/javascript');s.setAttribute('src', url);document.getElementsByTagName('head')[0].appendChild(s);

};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {

if(o.name === 'yahoo-dom-event'){ // YUI is ready}

};};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code function addScript(url){

var s = document.createElement('script');s.setAttribute('type', 'text/javascript');s.setAttribute('src', url);document.getElementsByTagName('head')[0].appendChild(s);

};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {

if(o.name === 'yahoo-dom-event'){ // YUI is ready}

};};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ // YUI is ready

}};

};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

You can extend that to load different YUI components one

after the other.

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

if(typeof o === 'undefined'){var APIurl = 'http://yui.yahooapis.com/2.3.1/' +

'build/yahoo-dom-event/' + 'yahoo-dom-event.js';

addScript(APIurl);} else {if(o.name === 'yahoo-dom-event'){ var url = 'http://yui.yahooapis.com/2.3.1/' +

'build/animation/' + 'animation-min.js';

addScript(url);}

};};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

var myScript = function(){// other code

+ function addScript(url){};function YUIready(o){

+ if(typeof o === 'undefined'){} else {if(o.name === 'yahoo-dom-event'){ var url = 'http://yui.yahooapis.com/2.3.1/' +

'build/animation/' + 'animation-min.js';

addScript(url);};if(o.name === 'animation'){

// done …};

};};YUIready();return { YUIready:YUIready };

}();YAHOO_config = { listener:myScript.YUIready };

You can also make it dependent on classes or IDs

used in the document, or configuration options of your main script and many more

things.

Have fun!

Thanks!