vitro/webapp/web/js/jquery_plugins/pagination/jquery.pagination.js

219 lines
6.9 KiB
JavaScript

/**
* This jQuery plugin displays pagination links inside the selected elements.
*
* This plugin needs at least jQuery 1.4.2
*
* @author Gabriel Birke (birke *at* d-scribe *dot* de)
* @version 2.0rc
* @param {int} maxentries Number of entries to paginate
* @param {Object} opts Several options (see README for documentation)
* @return {Object} jQuery Object
*/
(function($){
/**
* @class Class for calculating pagination values
*/
$.PaginationCalculator = function(maxentries, opts) {
this.maxentries = maxentries;
this.opts = opts;
}
$.extend($.PaginationCalculator.prototype, {
/**
* Calculate the maximum number of pages
* @method
* @returns {Number}
*/
numPages:function() {
return Math.ceil(this.maxentries/this.opts.items_per_page);
},
/**
* Calculate start and end point of pagination links depending on
* current_page and num_display_entries.
* @returns {Array}
*/
getInterval:function(current_page) {
var ne_half = Math.ceil(this.opts.num_display_entries/2);
var np = this.numPages();
var upper_limit = np - this.opts.num_display_entries;
var start = current_page > ne_half ? Math.max( Math.min(current_page - ne_half, upper_limit), 0 ) : 0;
var end = current_page > ne_half?Math.min(current_page+ne_half, np):Math.min(this.opts.num_display_entries, np);
return {start:start, end:end};
}
});
// Initialize jQuery object container for pagination renderers
$.PaginationRenderers = {}
/**
* @class Default renderer for rendering pagination links
*/
$.PaginationRenderers.defaultRenderer = function(maxentries, opts) {
this.maxentries = maxentries;
this.opts = opts;
this.pc = new $.PaginationCalculator(maxentries, opts);
}
$.extend($.PaginationRenderers.defaultRenderer.prototype, {
/**
* Helper function for generating a single link (or a span tag if it's the current page)
* @param {Number} page_id The page id for the new item
* @param {Number} current_page
* @param {Object} appendopts Options for the new item: text and classes
* @returns {jQuery} jQuery object containing the link
*/
createLink:function(page_id, current_page, appendopts){
var lnk, np = this.pc.numPages();
page_id = page_id<0?0:(page_id<np?page_id:np-1); // Normalize page id to sane value
appendopts = $.extend({text:page_id+1, classes:""}, appendopts||{});
if(page_id == current_page){
lnk = $("<span class='current'>" + appendopts.text + "</span>");
}
else
{
lnk = $("<a>" + appendopts.text + "</a>")
.attr('href', this.opts.link_to.replace(/__id__/,page_id));
}
if(appendopts.classes){ lnk.addClass(appendopts.classes); }
lnk.data('page_id', page_id);
return lnk;
},
// Generate a range of numeric links
appendRange:function(container, current_page, start, end) {
var i;
for(i=start; i<end; i++) {
this.createLink(i, current_page).appendTo(container);
}
},
getLinks:function(current_page, eventHandler) {
var begin, end,
interval = this.pc.getInterval(current_page),
np = this.pc.numPages(),
fragment = $("<div class='pagination'></div>");
// Generate "Previous"-Link
if(this.opts.prev_text && (current_page > 0 || this.opts.prev_show_always)){
fragment.append(this.createLink(current_page-1, current_page, {text:this.opts.prev_text, classes:"prev"}));
}
// Generate starting points
if (interval.start > 0 && this.opts.num_edge_entries > 0)
{
end = Math.min(this.opts.num_edge_entries, interval.start);
this.appendRange(fragment, current_page, 0, end);
if(this.opts.num_edge_entries < interval.start && this.opts.ellipse_text)
{
jQuery("<span>"+this.opts.ellipse_text+"</span>").appendTo(fragment);
}
}
// Generate interval links
this.appendRange(fragment, current_page, interval.start, interval.end);
// Generate ending points
if (interval.end < np && this.opts.num_edge_entries > 0)
{
if(np-this.opts.num_edge_entries > interval.end && this.opts.ellipse_text)
{
jQuery("<span>"+this.opts.ellipse_text+"</span>").appendTo(fragment);
}
begin = Math.max(np-this.opts.num_edge_entries, interval.end);
this.appendRange(fragment, current_page, begin, np);
}
// Generate "Next"-Link
if(this.opts.next_text && (current_page < np-1 || this.opts.next_show_always)){
fragment.append(this.createLink(current_page+1, current_page, {text:this.opts.next_text, classes:"next"}));
}
$('a', fragment).click(eventHandler);
return fragment;
}
});
// Extend jQuery
$.fn.pagination = function(maxentries, opts){
// Initialize options with default values
opts = jQuery.extend({
items_per_page:10,
num_display_entries:10,
current_page:0,
num_edge_entries:0,
link_to:"#",
prev_text:"Prev",
next_text:"Next",
ellipse_text:"...",
prev_show_always:true,
next_show_always:true,
renderer:"defaultRenderer",
callback:function(){return false;}
},opts||{});
var containers = this,
renderer, links, current_page;
/**
* This is the event handling function for the pagination links.
* @param {int} page_id The new page number
*/
function pageSelected(evt){
var links, current_page = $(evt.target).data('page_id');
containers.data('current_page', current_page);
links = renderer.getLinks(current_page, pageSelected);
containers.empty();
links.appendTo(containers);
var continuePropagation = opts.callback(current_page, containers);
if (!continuePropagation) {
if (evt.stopPropagation) {
evt.stopPropagation();
}
else {
evt.cancelBubble = true;
}
}
return continuePropagation;
}
current_page = opts.current_page;
containers.data('current_page', current_page);
// Create a sane value for maxentries and items_per_page
maxentries = (!maxentries || maxentries < 0)?1:maxentries;
opts.items_per_page = (!opts.items_per_page || opts.items_per_page < 0)?1:opts.items_per_page;
if(!$.PaginationRenderers[opts.renderer])
{
throw new ReferenceError("Pagination renderer '" + opts.renderer + "' was not found in jQuery.PaginationRenderers object.");
}
renderer = new $.PaginationRenderers[opts.renderer](maxentries, opts);
containers.each(function() {
// Attach control functions to the DOM element
this.selectPage = function(page_id){ pageSelected(page_id);}
this.prevPage = function(){
var current_page = containers.data('current_page');
if (current_page > 0) {
pageSelected(current_page - 1);
return true;
}
else {
return false;
}
}
this.nextPage = function(){
var current_page = containers.data('current_page');
if(current_page < numPages()-1) {
pageSelected(current_page+1);
return true;
}
else {
return false;
}
}
});
// When all initialisation is done, draw the links
links = renderer.getLinks(current_page, pageSelected);
containers.empty();
links.appendTo(containers);
// call callback function
opts.callback(current_page, containers);
}
})(jQuery);