OpenSlides/openslides/agenda/static/javascript/jquery.once.js
2012-04-25 22:48:27 +02:00

79 lines
2.9 KiB
JavaScript

/**
* jQuery Once Plugin v1.2
* http://plugins.jquery.com/project/once
*
* Dual licensed under the MIT and GPL licenses:
* http://www.opensource.org/licenses/mit-license.php
* http://www.gnu.org/licenses/gpl.html
*/
(function ($) {
var cache = {}, uuid = 0;
/**
* Filters elements by whether they have not yet been processed.
*
* @param id
* (Optional) If this is a string, then it will be used as the CSS class
* name that is applied to the elements for determining whether it has
* already been processed. The elements will get a class in the form of
* "id-processed".
*
* If the id parameter is a function, it will be passed off to the fn
* parameter and the id will become a unique identifier, represented as a
* number.
*
* When the id is neither a string or a function, it becomes a unique
* identifier, depicted as a number. The element's class will then be
* represented in the form of "jquery-once-#-processed".
*
* Take note that the id must be valid for usage as an element's class name.
* @param fn
* (Optional) If given, this function will be called for each element that
* has not yet been processed. The function's return value follows the same
* logic as $.each(). Returning true will continue to the next matched
* element in the set, while returning false will entirely break the
* iteration.
*/
$.fn.once = function (id, fn) {
if (typeof id != 'string') {
// Generate a numeric ID if the id passed can't be used as a CSS class.
if (!(id in cache)) {
cache[id] = ++uuid;
}
// When the fn parameter is not passed, we interpret it from the id.
if (!fn) {
fn = id;
}
id = 'jquery-once-' + cache[id];
}
// Remove elements from the set that have already been processed.
var name = id + '-processed';
var elements = this.not('.' + name).addClass(name);
return $.isFunction(fn) ? elements.each(fn) : elements;
};
/**
* Filters elements that have been processed once already.
*
* @param id
* A required string representing the name of the class which should be used
* when filtering the elements. This only filters elements that have already
* been processed by the once function. The id should be the same id that
* was originally passed to the once() function.
* @param fn
* (Optional) If given, this function will be called for each element that
* has not yet been processed. The function's return value follows the same
* logic as $.each(). Returning true will continue to the next matched
* element in the set, while returning false will entirely break the
* iteration.
*/
$.fn.removeOnce = function (id, fn) {
var name = id + '-processed';
var elements = this.filter('.' + name).removeClass(name);
return $.isFunction(fn) ? elements.each(fn) : elements;
};
})(jQuery);