Editor: Nguyễn Đức Minh Khôi

Email: nguyenducminhkhoi@gmail.com

HCMC University of Technology

@Jan, 2012

TRAINING JAVASCRIPT & jQUERY

Content

Introduction to JavaScript

JavaScript – the basic

Getting Started with JQuery

JQuery in Action

Ajax, tips, tricks

1/6/2012 2

Part1: Introduction to JavaScript

What is JavaScript and JQuery?

The Web World

Software for JavaScript programming

1/6/2012 3

What is JavaScript? JavaScript is a programming language that lets you

supercharge your HTML with animation, interactivity, and dynamic visual effects.

1/6/2012 4

What is jQuery? jQuery is a JavaScript library intended to make

JavaScript programming easier and more fun.

solves the two biggest headaches with JavaScript— complexity and the finicky nature of different web browsers.

you can add advanced features to your website with thousands of easy-to-use jQuery plug-ins.

1/6/2012 5

The web world HTML provides the structural layer, organizing content

like pictures and words in a meaningful way

CSS (Cascading Style Sheets) provides the presentational layer, making the content in the HTML look good

JavaScript adds a behavioral layer, bringing a web page to life so it interacts with web visitors and reduce “stress” for Server.

Other Server Scripting: PHP, ASP, JSP, Ruby, Python… do the main part of your project!

1/6/2012 6

Software for JS Programming Notepad++ (Windows, http://notepad-plus-plus.org) is a

coder’s friend. Netbeans (Windows, Linux, Mac; www.eclipse.org) is a

free, popular choice amongst Java Developers, but includes tools for working with HTML, CSS, and JavaScript.

Eclipse and Aptana Studio plugin (Windows, Linux, Mac; www.aptana.org) is a powerful, free coding environment with tools for working with HTML, CSS, JavaScript, PHP, and Ruby on Rails.

Dreamweaver (Mac and Windows, www.adobe.com/products/dreamweaver.html) is a visual web page editor.

Expression Web Designer (Windows, www.microsoft.com/expression/products/StudioWebPro_Overview.aspx) is Microsoft’s entry in the web design field.

1/6/2012 7

Software for JS Programming (cont’) Google Chrome browser and Developer tools (Ctr +

Shift + J)

Firefox and firebug plugin (http://getfirebug.com/)

Internet Explorer 9 – console (F12)

Safari and Error console (Ctrl + Alt + C)

Wamp Server (for Ajax practice) for windows www.wampserver.com/en/

Lamp Server for Linux (Debian, Ubuntu) http://www.sph.umich.edu/csg/abecasis/LAMP/download/

Mamp Server for Mac: www.mamp.info/en

1/6/2012 8

Editor: Nguyễn Đức Minh Khôi

Email: nguyenducminhkhoi@gmail.com

HCMC University of Technology

@Jan, 2012

TRAINING JAVASCRIPT & jQUERY

Content

Introduction to JavaScript

JavaScript – the basic

Getting Started with JQuery

JQuery in Action

Ajax, tips, tricks

1/6/2012 10

Part2: JavaScript – the Basics

Introduction to JavaScript

How to work with JavaScript

1/6/2012 11

Introduction to JavaScript How to add JS to a page:

Notes: if you use HTML earlier than HTML5 should:

1/6/2012 12

Introduction to JavaScript (cont.) URL type:

Absolute path: http://www.cosmofarmer.com/scripts/site.js

Use when you point to a file that’s not on the same server as the your web page.

Root relative: /scripts/site.js

Use for JavaScript files stored on your own site.

Document relative: ../scripts/site.js - ../ means climb up out of the folder

Use when you’re designing on your own computer without the aid of a web server.

1/6/2012 13

Introduction to JavaScript (cont.) JS is a client-side language which means that it works

inside a web browser.

JS is also a scripting language like PHP, Ruby, Python ColdFusion as well.

JS is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles.

JavaScript was formalized in the ECMAScript language standard.

JavaScript uses syntax influenced by that of C. And very different sematic with Java.

See more at http://www.w3schools.com/js/default.asp

1/6/2012 14

Introduction to JavaScript (cont.) Statement

Basic programming unit E.g.: alert('Hello World!');

Popup Box: alert(‚Be alert‛) // alert something with user prompt(‚enter sth‛)//ask user to input something confirm("Press a button!");

Built in function document.write() //add content to a page isNaN(variable) //check if variable is a number Number(variable) // convert to number or NaN String(variable) // convert to string

Data Type Number: 5, 5.125, NaN (just– Double) String: ‘Hello’, ‚Hello‛, ‚Hello ’World’ !‛, ‚\’a‛, ‚Hello‛World‛!‛

Boolean: true, false Object null, undefined

1/6/2012 15

Introduction to JavaScript (cont.) Variable

Declare: var + varName; Name: abc ≠ Abc, $abc, _abc, a123, 1bcd, alert Assign: varName = value; Show values: alert(varName);

Operation: Boolean op: ==, != , ===, !==, >, < , >=, <=, &&, ||, ! Number op: 3 + 4, 3 / 4, 3 * 4, 3 – 4 String op: ‘abc’ + ‘def’; Mix: ‘12’ + 4 = ‘124’; +’123’ + 4 = 127; Number(‘123’) + 4 = 127; ‘12’ * 4 = 48;

Complex op: ++, --, *=, /=, +=, -= Ternary op: (condition) ? A : B

1/6/2012 16

Introduction to JavaScript (cont.) Comment:

//this is a comment inline

/*

something to comment in many lines

*/

Array (List in real) Declare: var arr = [1, 2, 3]; or

var arr = new Array(1, 2, 3);

Access: arr[0];

Notes: Empty array: var arr = [];

Mix types: var arr = [1, 2, ‘abc’, true, [3, 4,5]];

1/6/2012 17

Introduction to JavaScript (cont.) Array op:

1/6/2012 18

Introduction to JavaScript (cont.) If Statement:

Switch Statement:

switch(n) { case 1: execute code block 1 break; case 2: execute code block 2 break; default: code to be executed if n is different from case 1 and 2 }

if ( condition1 ) { // door #1 } else if (condition2) { // door #2 } else { // door #3 }

1/6/2012 19

Introduction to JavaScript (cont.) While Statement: while (condition) { // javascript to repeat } Do while Statement: do { // javascript to repeat } while (condition) ; For Statement: for (var count = 0; count < MaxLoop; count++){

// javascript to repeat }

1/6/2012 20

Introduction to JavaScript (cont’) Break Statement: while (condition) {

// javascript to repeat

if (i==3){

break;

}

}

Continue Statement: do {

if (i==3){

continue;

}

} while (condition) ;

For in Statement: for (variable in object){ code to be executed }

1/6/2012 21

Introduction to JavaScript (cont.) Function: function functionName(parameters){

// the JavaScript you want to run

return value;

}

Anonymous function: (lambda function)

function (parameter1, parameter2){

// the JavaScript you want to run

return value;

}

1/6/2012 22

Introduction to JavaScript (cont.) Global vs. local variable: var paramenter = 3;

function func1(){

alert(parameter); // alert(3)

var parameter = 5;

alert(parameter); // alert(5)

}

func1();

Try, catch, throws: try{ //Run some code here

throw ‚Error‛; } catch(err) { //Handle errors here }

Put variable as a reference definitions at the beginning of your script 1/6/2012 23

How to work with JavaScript? Work with String:

Determine length of a string: strVar.length

Changing case of a string: strVar.toUpperCase()

or strVar.toLowerCase()

Searching String: strVar.indexOf(‘strSearch’)

Extract part of a String: strVar.slice(start, [end])

1/6/2012 24

How to work with JavaScript? (cont.) Work with Regular Expression:

1/6/2012 25

How to work with JavaScript? (cont.) Work with Regular Expression:

Useful Regex: U.S. Zip code:

U.S. Phone #:

Email Address:

Date:

Web Address:

1/6/2012 26

How to work with JavaScript? (cont.) Work with Number:

JavaScript interpreter usually converts a string to a number when it seems like a number is called for. For example: but:

Number():

ParseInt():

ParseFloat():

Test a Number:

1/6/2012 27

How to work with JavaScript? (cont.) Work with Number (next):

Math.round(), Math.ceil(), Math.floor():

Formatting currency:

Creating Random number:

Selecting random number:

Selecting randomly element of array:

1/6/2012 28

How to work with JavaScript? (cont.) Work with Dates and Times:

Declare:

1/6/2012 29

How to work with JavaScript? (cont.) Work with Dates and Times (next):

Getting the month:

Getting the Day of a week:

Creating Day other than today:

1/6/2012 30

How to work with JavaScript? (cont.) Work with Dates and Times (next):

Getting the time format (e.g.: 12:03:59 a.m.):

1/6/2012 31

Editor: Nguyễn Đức Minh Khôi

Email: nguyenducminhkhoi@gmail.com

HCMC University of Technology

@Jan, 2012

TRAINING JAVASCRIPT & jQUERY

Content

Introduction to JavaScript

JavaScript – the basic

Getting Started with jQuery

jQuery in Action

Ajax, tips, tricks

1/6/2012 33

Part3:Getting Started with jQuery

Selecting Element of a page

Attach an Event to Elements

Response Events by doing sth

1/6/2012 34

Introduction to jQuery Why use jQuery?

Relatively small file size

Friendly to web designers

It’s tried and true

It’s free

Large developer community

Plugins

How to use? Link to jQuery file on CDN server: <script src= "http://ajax.googleapis.com/ajax/libs/jquery/1.6.3/jquery.m in.js"></script>

Download jQuery file: http://docs.jquery.com/Downloading_jQuery.

<script src="js/jquery-1.6.3.min.js"></script>

1/6/2012 35

Introduction to jQuery (cont.) Some useful jQuery plugin:

jQuery-color: https://github.com/jquery/jquery-color

jQuery-easing: http://gsgd.co.uk/sandbox/jquery/easing/

JQuery-fancybox: http://fancybox.net/

JQuery-scrollTo: http://plug-ins.jquery.com/project/ScrollTo

jQuery-navigation: www.pollenizer.com/jquery-navigation-plugin/

jQuery-UI: http://jqueryui.com/download

jQuery-qTip: http://craigsworks.com/projects/qtip2/

jQuery Raty - A Star Rating: http://www.wbotelhos.com/raty/

jQuery Flickr: http://johnpatrickgiven.com/jquery/flickr-gallery/

jQuery-Ajax Form plugins: http://jquery.malsup.com/form/

jQuery-Ajax Autocomplete: http://jqueryui.com/demos/auto-complete/

jQuery-Ajax Uploadfile: http://www.uploadify.com/download/

jQuery-Ajax twitter: http://tweet.seaofclouds.com/

jQuery-Ajax Google Map: http://www.pittss.lv/jquery/gomap/

1/6/2012 36

Selecting Element of a page Notes:

put your JavaScript programming (all your <script> tags) after any other content inside the <head> tag, but before the closing </head> tag.

<script>

$(document).ready(function() {

// your programming goes here

}); // end ready

</script>

Or use for short:

<script>

$(function() {

// your programming goes here

}); // end ready

</script>

1/6/2012 37

Selecting Element of a page (cont.)

1/6/2012 38

1/6/2012 39

1/6/2012 40

Selecting Element of a page (cont.) Select page element (examples)

Basic Selector (like CSS selector) Id selector: var messagePara = $('#message'); Tag selector: var linksList = $('a'); Class selector: var a = $('.submenu');

Advanced Selector Descendent selector: $('#navBar a') Child selector: $(‘body > p') Adjacent sibling selector: $('h2 + div') Attribute selector: $('img[alt]')

jQuery filter $('p:first'); $('p:last'); $('p:odd'); $('p:even');

$('a:not(.navButton)'); $('li:has(a)'); $('a:contains(Click Me!)'); $('div:hidden').show(); $('div:visible').show();

1/6/2012 41

Selecting Element of a page (cont.) jQuery selection principles

Automatic loops: $('#slideshow img').hide();

Chaining function: $('#popUp').width(300).height(300);

Useful functions:

1/6/2012 42

1/6/2012 43

1/6/2012 44

1/6/2012 45

Selecting Element of a page (cont.) $('#errors').html();

$('#errors').html('<p>There are four errors in this form</p>');

$('#errors h2').text('No errors found');

$('#errors').append('<p>There are four errors in this form</p>');

$('#errors').prepend('<p>There are four errors in this form</p>');

$('#userName').after('<span class="error">User name required</span>');

$('#product101').replaceWith(<p>Added to cart</p>');

$('a[href^="http://"]').addClass('externalLink');

$('#alertBox').removeClass('highlight');

$('body').toggleClass('altStyle');

$('#main').css('background-color');

$('body').css('font-size', '200%');

var imageFile = $('#banner img').attr('src');

$('body').removeAttr('bgColor'); 1/6/2012 46

Selecting Element of a page (cont.) Notes:

Changing Multiple CSS Properties at Once

Each function:

$(this): element loop through all elements.

1/6/2012 47

Attach an Event to Elements Types of events:

1/6/2012 48

1/6/2012 49

1/6/2012 50

1/6/2012 51

Attach an Event to Elements (cont) Using Event – the jQuery Way:

1/6/2012 52

Attach an Event to Elements- e.g.

1/6/2012 53

Response Events by doing sth jQuery Effects:

1/6/2012 54

Response Events by doing sth (cont.) Examples:

1/6/2012 55

Response Events by doing sth (cont.) jQuery Animations:

Some attr are built-in (no need plugins)

Some attr need plugins: jquery-color: https://github.com/jquery/jquery-color

jquery-easing: http://gsgd.co.uk/sandbox/jquery/easing/

How to use:

1/6/2012 56

Notes: with hyphens: in CSS use 1 of these:

can use += or -= in CSS attr:

No use shorthands:

Response Events by doing sth (cont.)

1/6/2012 57

Response Events by doing sth (cont.) Using Easing:

Callback function: a function that runs only after the effect is completed.

1/6/2012 58

Editor: Nguyễn Đức Minh Khôi

Email: nguyenducminhkhoi@gmail.com

HCMC University of Technology

@Jan, 2012

TRAINING JAVASCRIPT & jQUERY

Content

Introduction to JavaScript

JavaScript – the basic

Getting Started with jQuery

jQuery in Action

Ajax, tips, tricks

1/6/2012 60

Part3: jQuery in Action

Improving your images

Improving navigation

Enhancing Web forms

Expanding your interfaces

1/6/2012 61

jQuery in Action Notes:

var newPara = $(‘<p>Hello</p>’) creates a new paragraph tag containing the word Hello.

var $banner = $('#banner'); The dollar sign reminds you that the variable holds a jQuery selection and not just any old value like a number or a string. This part is just giving you some basic techniques to do with

jQuery, for more information, you should lookup some tutorial in the main reference book “Java-jQuery the Missing Manual” - Part 3. This will give you more clearly about this techniques. And practice some tutorials in this books for conquer the idea.

You should download and see the usage of the plugins in listed in the slide #34 of this slides.

1/6/2012 62

Improving your images Changing an Image’s src Attribute:

Preloading Images

tells the web browser to actually download the new image

1/6/2012 63

Improving your images (cont.) Rollover images:

Just an image swap triggered by the mouse moving over an image

1/6/2012 64

Improving navigation Open External links in new Windows:

location.protocol stores the object’s protocol property like http or https

location.hostname stores the object’s host name like www.google.com

The not() function is a useful way of excluding some elements from a jQuery selection

Creating new Windows:

to close:

1/6/2012 65

Improving navigation (cont.) Opening page within a page – fancy box plugin

Navigation Bar Plugin

1/6/2012 66

Enhancing Web Forms Getting and Setting Form value Element:

Determining Whether Buttons and Boxes Are Checked

Form events:

Submit: validate

Username is input

Don’t do that or not follow that

links

1/6/2012 67

Enhancing Web Forms (Cont.) Focus: (input text, default value will disappear)

Blur: (check recently input box is correct)

Click:

Change:

1/6/2012 68

Enhancing Web Forms (cont.) Adding smart to your form:

Focus the first field in the form:

Disabling and Enabling Fields:

Hiding and Showing form option:

1/6/2012 69

Enhancing Web Forms (cont.) Form validation plugin

Basic validation:

Adding validation rules:

Adding Error message:

Advanced validation: (see more at the book)

1/6/2012 70

Expanding your Interface Organizing Information in Tabbed Panel

Adding a Content Slider to Your site

Determining the Size and Position of Page Element

Adding Tooltips

(See more at the book)

1/6/2012 71

Editor: Nguyễn Đức Minh Khôi

Email: nguyenducminhkhoi@gmail.com

HCMC University of Technology

@Jan, 2012

TRAINING JAVASCRIPT & jQUERY

Content

Introduction to JavaScript

JavaScript – the basic

Getting Started with JQuery

JQuery in Action

Ajax, tips, tricks

1/6/2012 73

Part3:Ajax, Tips and Tricks

What is Ajax?

JSON

Tips and tricks

1/6/2012 74

What is Ajax? stands for Asynchronous JavaScript and XML

not an “official” technology like HTML, JavaScript, or CSS.

refers to the interaction of a mix of technologies—JavaScript, the web browser, and the web server—to retrieve and display new content without loading a new web page

What you can do with Ajax:

Display new HTML content without reloading the page

Submit a form and instantly display results

Log in without leaving the page

Star-rating widget

Browsing through database information.

1/6/2012 75

What is Ajax? (cont.) Know more about web server:

Web server: stores documents and when a web browser asks for a document, the web server delivers it. (Apache, IIS,…)

Web application: understands a server-side programming language like PHP, Java, Ruby, Python. perform tasks that aren’t possible with only an HTML page, like sending email, storing information in a database.

Web database: store information like the names and addresses of customers, details of products you sell, or an archive of your favorite recipes. (e.g.: MySQL, PostgreSQL, SQL Server…

1/6/2012 76

What is Ajax? (cont.) How does Ajax work?

1/6/2012 77

What is Ajax? (cont.) Ajax talks with sever:

Create an instance of the XMLHttpRequest object.

var newXHR = new XMLHttpRequest();

Use the XHR’s open() method to specify what kind of data you’ll send and where the data will go

newXHR.open('GET', 'shop.php?productID=34');

Create a function to handle the results: use callback function

Send the request

newXHR.send('q=javascript');

Receive the response

1/6/2012 78

What is Ajax? (cont.) Ajax – the jQuery way:

1/6/2012 79

What is Ajax? (cont.) Ajax – the jQuery way:

Use .load() function:

Use: get HTML from a web server and inject it into a page.

Notes: Just use root-relative links, or make sure the file you load is located in the same directory as the page that’s using the load() function.

Use .get() and .post() function:

When you get(): when you want to get information, like requesting

the price of a particular product or obtaining a list of most popular products.

When use post(): when sending data that will change information on the server, like a request to delete a file, update a database, or insert new information into a database.

1/6/2012 80

What is Ajax? (cont.) Query String:

Notes: have to escape and encode query string, like:

Object Literal:

jQuery Serialize function(): collects all of the field names and the values currently in each field and creates a single query string.

Processing data from Server:

Handling Error:

1/6/2012 81

What is Ajax? (cont.)

data could be plain text, HTML, XML, or JSON

1/6/2012 82

JSON Stands for JavaScript Object Notation

is usually better than XML;

JSON is JavaScript, it works quickly and easily in JavaScript program.

getJSON() function:

1/6/2012 83

JSON (cont.) Access JSON Data:

Simple data:

Complex data:

1/6/2012 84

JSONP b/c Ajax requests are limited to the same domain.

stands for JSON with padding. provides one way to retrieve information from another site.

Ajax request of the foreign site, you load a script that contains the JSON code in it. Or linking to an external JavaScript file on Google.

For example:

1/6/2012 85

Tips and tricks Useful tips:

$() Is the Same as jQuery()

like

Saving selections into variables

Or use chaining:

Instead of :

Putting reference in variable:

1/6/2012 86

Tips and tricks (cont.) Adding contents few times as possible

Use:

Optimize your selector: Use ID selectors if at all possible.

Use IDs first, as part of a descendent selector.

Use find function:

NOT

1/6/2012 87

Tips and tricks (cont.) Using the jQuery docs efficiently:

http://docs.jquery.com/ (especially the jQuery API)

Compress your JavaScript and other file before deploy your website: http://developer.yahoo.com/yui/compressor

Use firebug – Firefox plugin debugger efficiently

http://www.youtube.com/watch?v=1rfiPaWz4No

jQuery plugin site: http://plugins.jquery.com/

jQuery UI site: http://jqueryui.com

1/6/2012 88

Conclusion

JavaScript is great, but it is also

difficult for you to conquer, you

should use jQuery instead!

jQuery isn’t only about simpler code and being more productive.

It is also about great community, support, tutorials, plugins, open (free) license, test coverage books, speed, light weight code

Keep the jQuery cheat sheet beside you when working with jQuery

Practice the tutorial in main reference book!

1/6/2012 89

References JavaScript and jQuery the missing manual, 2nd Edition

2011- David Sawyer McFarland

JavaScript 1.6 Visual Cheat Sheet

Suggest Reading jQuery in Actions by Bear Bibeault and Yehuda Katz

Head First JavaScript by Michael Morrison (O’Reilly)

1/6/2012 90

Editor: Nguyễn Đức Minh Khôi

Email: nguyenducminhkhoi@gmail.com

Thanks for your watching!