Book Image

jQuery UI 1.7: The User Interface Library for jQuery

Book Image

jQuery UI 1.7: The User Interface Library for jQuery

Overview of this book

Modern web application user interface design requires rapid development and proven results. jQuery UI, a trusted suite of official plug-ins for the jQuery JavaScript library, gives you a solid platform on which to build rich and engaging interfaces with maximum compatibility and stability, and minimum time and effort. jQuery UI has a series of ready-made, great-looking user interface widgets and a comprehensive set of core interaction helpers designed to be implemented in a consistent and developer-friendly way. With all this, the amount of code that you need to write personally to take a project from conception to completion is drastically reduced. Specially revised for version 1.7 of jQuery UI, this book has been written to maximize your experience with the library by breaking down each component and walking you through examples that progressively build upon your knowledge, taking you from beginner to advanced usage in a series of easy-to-follow steps. In this book, you'll learn how each component can be initialized in a basic default implementation and then see how easy it is to customize its appearance and configure its behavior to tailor it to the requirements of your application. You'll look at the configuration options and the methods exposed by each component's API to see how these can be used to bring out the best of the library. Events play a key role in any modern web application if it is to meet the expected minimum requirements of interactivity and responsiveness, and each chapter will show you the custom events fired by the component covered and how these events can be intercepted and acted upon.
Table of Contents (19 chapters)
jQuery UI 1.7
Credits
About the Author
About the Reviewers
Preface
Index

Droppable event callbacks


The options that we've looked at so far configure various operational features of the droppable. In addition to these, there are almost as many callback options so that we can define functions that react to different things occurring to the droppable and its accepted drag objects. These options are listed below.

Callback option

Invoked

activate

When an accepted drag object begins dragging.

deactivate

When an accepted drag object stops being dragged.

drop

When an accepted drag object is dropped onto a droppable.

out

When an accepted drag object is moved out of the bounds (including the tolerance) of the droppable.

over

When an accepted drag object is moved within the bounds (including the tolerance) of the droppable.

Let's put together a basic example that makes use of these callback options. We'll add a status bar to our droppable that reports the status of different interactions between the drag object and the droppable. In droppable4.html add the following...