Drupal 6 JavaScript and jQuery - Ebook-Cours.com

AJAX and Drupal Web Services
Views is capable of creating very complex queries against the Drupal database. It
does the heavy lifting automatically, without requiring you to (for example) write
the SQL to retrieve information from the database. Part of this automation process
requires the generation of field names that are unlikely to conflict with other fields in
the returned results. Therefore, it uses a rather complex naming convention to assign
field names.
We now have our view constructed. We will now turn to the JavaScript code that
will run on the client.
The comment watcher
We have just configured the server to give us the information we need in order
to find out what the latest comment is, using AJAX and JSON. In this section, we
will develop a JavaScript tool that will use this information in order to generate
comment notifications.
The script will watch the JSON feed for changes. When a new comment appears in
the JSON feed, the comment watcher will notify the user.
To create our script, we are going to draw on our existing toolkit, using behaviors,
theming, and jQuery to build the comment watcher.
Let's first take a glance at the code in its entirety. We will then take a closer look at
each section. This code is from the script commentwatcher.js, which is loaded into
our theme using a scripts[] = commentwatcher.js directive in the info file:
// $Id$
/**
* Watch for new comments and display a message when a comment
* is posted.
*
* @file
*/
var CommentWatcher = CommentWatcher || {settings: {}};
CommentWatcher.settings.path = 'newest_comment';
CommentWatcher.settings.maxLength = 128;
CommentWatcher.settings.showSeconds = 7;
CommentWatcher.settings.checkSeconds = 10;
Drupal.behaviors.commentWatcher = function () {
if ($('#comment_watcher').length == 0) {
$('body').append('');
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This material is copyright and is licensed for the sole use by Richard Ostheimer on 18th June 2009
2205 hilda ave., , missoula, , 59801