BEGINNING JQUERY

Dr. Chiang

Dhruv Gairola (TA)

Outline

What is jQuery? Why use jQuery? Examples.

AJAX DOM traversal Event handling

Upgrades. Other libraries. jQuery related products. Conclusion.

What is jQuery?

Javascript library. Released January 2006. Version 1.x and 2.x. 2.x does not work < IE9

Why use jQuery?

Less coding. Simplify event handling. Simplify AJAX. Simplify DOM traversal. Handling of cross browser issues. Popular and useful client frameworks

depend on jQuery e.g., Bootstrap, Ember.js Lot of plugins available. etc

Examples – AJAX.

Asynchronous Javascript and XML. XML not necessary, JSON also possible. Demo.

Examples – AJAX.

Examples – AJAX.

Examples – DOM traversal.

You can traverse the DOM tree pretty easily. Demo.

Examples – Event handling.

Bind listeners to your objects. Callbacks. Demo.

Upgrades.

Upgrading is essential part of jQuery. jQuery migrate plugin. Automated tests (e.g., Selenium) should

reveal problems. Manual correction thereafter.

Other libraries.

Mootools has more functionality. Some UI components included in core.

jQuery is easier to learn. Lot of jQuery plugins. Readable code. Chaining of methods. Good documentation.

Nice comparison : http://www.slideshare.net/jeresig/javascript-library-overview-presentation/

jQuery related products.

jQuery UI : Front end effects, widgets, themes, etc.

jQuery mobile : Front end framework. Demos.

Conclusion.

Useful framework. Very popular in industry. Lot of plugins. CDNs hosted jQuery code, so browser

loading time isn’t significantly hit.