regluit/static/js/jquery.endless-scroll.js

133 lines
4.9 KiB
JavaScript

/**
* Endless Scroll plugin for jQuery
*
* v1.4.8
*
* Copyright (c) 2008 Fred Wu
*
* Dual licensed under the MIT and GPL licenses:
* http://www.opensource.org/licenses/mit-license.php
* http://www.gnu.org/licenses/gpl.html
*/
/**
* Usage:
*
* // using default options
* $(document).endlessScroll();
*
* // using some custom options
* $(document).endlessScroll({
* fireOnce: false,
* fireDelay: false,
* loader: "<div class=\"loading\"><div>",
* callback: function(){
* alert("test");
* }
* });
*
* Configuration options:
*
* bottomPixels integer the number of pixels from the bottom of the page that triggers the event
* fireOnce boolean only fire once until the execution of the current event is completed
* fireDelay integer delay the subsequent firing, in milliseconds, 0 or false to disable delay
* loader string the HTML to be displayed during loading
* data string|function plain HTML data, can be either a string or a function that returns a string,
* when passed as a function it accepts one argument: fire sequence (the number
* of times the event triggered during the current page session)
* insertAfter string jQuery selector syntax: where to put the loader as well as the plain HTML data
* callback function callback function, accepts one argument: fire sequence (the number of times
* the event triggered during the current page session)
* resetCounter function resets the fire sequence counter if the function returns true, this function
* could also perform hook actions since it is applied at the start of the event
* ceaseFire function stops the event (no more endless scrolling) if the function returns true
*
* Usage tips:
*
* The plugin is more useful when used with the callback function, which can then make AJAX calls to retrieve content.
* The fire sequence argument (for the callback function) is useful for 'pagination'-like features.
*/
(function($){
$.fn.endlessScroll = function(options) {
var defaults = {
bottomPixels: 50,
fireOnce: true,
fireDelay: 150,
loader: "<br />Loading...<br />",
data: "",
insertAfter: "div:last",
resetCounter: function() { return false; },
callback: function() { return true; },
ceaseFire: function() { return false; }
};
var options = $.extend({}, defaults, options);
var firing = true;
var fired = false;
var fireSequence = 0;
if (options.ceaseFire.apply(this) === true) {
firing = false;
}
if (firing === true) {
$(this).scroll(function() {
if (options.ceaseFire.apply(this) === true) {
firing = false;
return; // Scroll will still get called, but nothing will happen
}
if (this == document || this == window) {
var is_scrollable = $(document).height() - $(window).height() <= $(window).scrollTop() + options.bottomPixels;
} else {
// calculates the actual height of the scrolling container
var inner_wrap = $(".endless_scroll_inner_wrap", this);
if (inner_wrap.length == 0) {
inner_wrap = $(this).wrapInner("<div class=\"endless_scroll_inner_wrap\" />").find(".endless_scroll_inner_wrap");
}
var is_scrollable = inner_wrap.length > 0 &&
(inner_wrap.height() - $(this).height() <= $(this).scrollTop() + options.bottomPixels);
}
if (is_scrollable && (options.fireOnce == false || (options.fireOnce == true && fired != true))) {
if (options.resetCounter.apply(this) === true) fireSequence = 0;
fired = true;
fireSequence++;
$(options.insertAfter).after("<div id=\"endless_scroll_loader\">" + options.loader + "</div>");
data = typeof options.data == 'function' ? options.data.apply(this, [fireSequence]) : options.data;
if (data !== false) {
$(options.insertAfter).after("<div id=\"endless_scroll_data\">" + data + "</div>");
$("div#endless_scroll_data").hide().fadeIn();
$("div#endless_scroll_data").removeAttr("id");
options.callback.apply(this, [fireSequence]);
if (options.fireDelay !== false || options.fireDelay !== 0) {
$("body").after("<div id=\"endless_scroll_marker\"></div>");
// slight delay for preventing event firing twice
$("div#endless_scroll_marker").fadeTo(options.fireDelay, 1, function() {
$(this).remove();
fired = false;
});
}
else {
fired = false;
}
}
$("div#endless_scroll_loader").remove();
}
});
}
};
})(jQuery);