1. Client-side technologies
jQuery and Dojo
Jan Holz, Helen Magiera, Yousef Hatem, Michael Schlimnat
Web Technologies – Prof. Dr. Ulrik Schroeder – WS 2010/111
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2. Overview
1. Dojo
1. What is Dojo? Why Dojo?
2. How to get Dojo
3. Toolkit Overview
4. Dojo Demo
2. jQuery
1. What is jQuery?
2. jQuery UI
3. A quick introduction to jQuery
4. The ready() function
5. Geting started with jQuery: Examples
3. Summery/ Conclusion
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3. 1.1 What is Dojo? Why Dojo?
 JavaScript Toolkit
 Makes web development projects easy to realize
 Save time by spending less effort on the common tasks
 spend more time on the really interesting aspects of a web project
 Some further Reasons:
 Big Community
 Open source software
 Provides end-to-end solution
 Portability
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4. 1.2 How to get Dojo
 Dojo From Google CDN/AOL CDN:
Easy embedding into your website
 Dojo From Google CDN:
<script
src="http://ajax.googleapis.com/ajax/libs/dojo/1.5/dojo/dojo.xd.js"
type="text/javascript"></script>
 Dojo From AOL CDN:
<script src="http://o.aolcdn.com/dojo/1.5/dojo/dojo.xd.js"
type="text/javascript"></script>
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5. 1.3 Toolkit Overview
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Dojo
DojoX UtilDijit
Base Core

6. 1.3 Toolkit Overview
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Dojo
DojoX UtilDijit
Base Core

7. 1.3 Toolkit Overview
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Dojo
Base
 included in the base-level
dojo namespace: dojo.js
 most commonly used
functions

8. 1.3 Toolkit Overview
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Dojo
Base Core
 supplements base with additional
functions
 call it with dojo.require-fuction:
dojo.require("dojo.dnd.Mover");
kinds of features:
• animation machinery: dojo.fx
• drag-and-drop facilities: dojo.dnd
• data management layer: dojo.data
• cookie handling: dojo.cookie
• back-button handling: dojo.back
• many more

9. 1.3 Toolkit Overview
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Dojo
Dijit
Base Core
 Library of widgets (short for “Dojo widget”)
 Out of the box: doesn’t require any
JavaScript at all
 Widgets created with dijit are ultra-
portable and can be shared onto any web
server
 Plugging in with dojoType inside of
ordinary html-tags
<script type="text/javascript"> dojo.require("dijit.form.Textarea");
</script>
...
<textarea id="textarea2" name="textarea2"
dojoType="dijit.form.Textarea" style="width:200px;"> Blabla
</textarea>
Divided into:
• general-purpose application widgets
(progress bars, Calendars, …)
• layout widgets (tab containers,…)
• form widgets (button, input elements,…)

10. 1.3 Toolkit Overview
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Dojo
DojoXDijit
Base Core
• Area for development of extensions to the
Dojo toolkit
• managed by subprojects (each contains
readme.txt)

11. 1.3 Toolkit Overview
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Dojo
DojoX UtilDijit
Base Core Contains JavaScript unit-testing
framework
 tool for creating custom versions
of dojo

12. 1.3 Toolkit Overview
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Dojo
DojoX UtilDijit
Base Core

13. 1.4 Dojo Demo
 Huge API, we will introduce only a few
 Some clever wrappers for the usual old JS functions
 Drag and Drop
 Context Menus
 Collecting data from data stores
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14. 1.4 Another perspective of searching!
 Welcome to Google <3 Dojo website!
 Relies on Google search engine to get the results.
 uses Dojo to give the user a rich experience: take a sneak look at
the website, add the search result to favorites bucket, and
highlight them using different colors.
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15. 1.4 Dojo Syntactic Sugars
 Extensions to JavaScript basic functions and constructs
 Querying elements flexibly:
 dojo.query('#foo .bar > h3')
 Iteration on elements cannot be easier:
 dojo.query(“foo").forEach( function(fooTag) {fooTag.disabled =
true; } );
 Using signal-slot system to wire up the system
 dojo.connect(exampleObj, "foo", exampleObj, "bar");
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16. 1.4 Dojo – Fetching Data from a DataStore
 Dojo introduces a uniform way of accessing data.
dojo.require("dojox.data.GoogleSearchStore");
var search = new dojox.data.GoogleSearchStore();
search.fetch(
{
query: { text: queryText },
count: 20,
onComplete: callback //handles the returned data
}
);
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17. 1.4 Dojo – Fetching Data from a DataStore2
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function callback(items){
//string array
var strings = new Array();
//put the results in a matrix
dojo.forEach(items, function(item){
strings.push("<b>" + search.getValue(item,
"title") + "<b><br/><a href="" +
search.getValue(item, "url") +
"">"+search.getValue(item, "url")+"</a>"); });
//now we have the data stored in strings
}

18. 1.4. Dojo - DnD
 Dojo offers a very neat cross platform way for drag and drop
 Define a source, a destination, and Dojo will do the magic!
dojo.require("dojo.dnd.Source");
var dragList = new dojo.dnd.Source(“someNode");
var dropList = new dojo.dnd.Target(“someOtherNode");
 To add elements to the drag list, simply use insertNodes
and according the type to DOM element which the drag list is
wrapping, dojo will create the appropriate list element
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19. 1.4. Dojo – Context Menu
 Dojo offers an easy way to incorporate menus in a website
 There are so many type of menus that Dojo supports
dojo.require("dijit.Menu");
pMenu = new dijit.Menu();
pMenu.addChild(new dijit.MenuItem({label:"Menu
Item", onClick:function(){alert (“I am
hit!");}));
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20. 2.1 What is jQuery?
 JavaScript library
 makes navigating through HTML and CSS elements easier
 intuitive Event Handling functionalities
 animations
 ajax support
 Download jquery.js at jQuery.com
 include <script type="text/javascript" src="jquery.js"></script> in
the <head>
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21. 2.2 jQuery UI
 additional low-level interactions
 e.g. drag and drop and resize items
 variety of widgets
 advanced effects
 customizable download
 select which modules should be downloaded
 built on top of jQuery
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22. 2.3 A quick introduction to jQuery
 $ alias for jQuery class
 $() constructs a jQuery object (alias for jQuery())
 takes css classes and IDs, html elements and XPath expressions as
arguments
 e.g $(“.myClass”) represents .myClass
 advantage of jQuery: intuitive element selector functionality
 don't use document.getElementByID anymore
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23. 2.4 The ready() function
 Start with this:
 $(document).ready(function(){ // put your code here});
 or shorter: $(function(){ // your code});
 executes the code when DOM is constructed
 use instead of window.onload = function(){ // executed when page
is loaded}
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24. 2.5 Getting started with jQuery
Enough theory, now we...
 use a hover effect
 change "static" text in realtime
 introduce some animations
 code a small jQuery plugin
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25. 2.5 Getting started with jQuery
We have...
...a plain html/css site (bit.ly/jQdemo)
We want...
…a clean separation of functionality and structure
We need...
...the DOM for jQuery to read/manipulate it
→ $(document).ready(function() { … });
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26. 2.5 Getting started with jQuery
A glimpse of code
 $ == jQuery == window.jQuery
 $(object).someFunction();
 $(object).someFunction($(obj).prevFunction());
 $(object1).someFunction(function() {
 $(object2).nextFunction();
 });
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27. Summary/ Conclusion
 Both are pretty fast JS-Frameworks
 Both offer almost the same functionality
 Dojo offers more fine-grained libraries (dojo.require)
→ choose the one you like best
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hover with Dojo:
dojo.query("p").forEach(function(node){
node.onmouseover = function(){
dojo.addClass(node, "red");
}
node.onmouseout = function(){
dojo.removeClass(node, "red");
}
});
hover with jQuery:
$("p").hover(function() {
$(this).addClass("red");
},function(){
$(this).removeClass("red");
});

28. Literature
 Books: M.A. Russell – Dojo. The definitive Guide
 Tutorials: http://www.sitepen.com/blog/series/dojo-quick-start-
guide/
 Links: http://www.dojotoolkit.org
 Dojo Official Website, API Documentation:
 http://api.dojotoolkit.org/
 Dojo.Campus.org
 http://dojocampus.org/
 Practical Dojo Project, Frank W. Zammetti
 APress publications, ISBN-13 (pbk): 978-1-4302-1066-5
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