silverstripe-framework/javascript/core/jquery.ondemand.js
Andrew O'Neil 635e2c3df6 Merged from 2.3
git-svn-id: svn://svn.silverstripe.com/silverstripe/open/modules/sapphire/trunk@72453 467b73ca-7a2a-4603-9d3b-597d59a354a9
2009-03-04 03:44:11 +00:00

233 lines
6.9 KiB
JavaScript

/**
* On-demand JavaScript handler
* Based on http://plugins.jquery.com/files/issues/jquery.ondemand.js_.txt and modified to integrate with Sapphire
*/
(function($){
function isExternalScript(url){
re = new RegExp('(http|https)://');
return re.test(url);
};
$.extend({
requireConfig : {
routeJs : '', // empty default paths give more flexibility and user has
routeCss : '' // choice of using this config or full path in scriptUrl argument
}, // previously were useless for users which don't use '_js/' and '_css/' folders. (by PGA)
queue : [],
pending : null,
loaded_list : null, // loaded files list - to protect against loading existed file again (by PGA)
// Added by SRM: Initialise the loaded_list with the scripts included on first load
initialiseItemLoadedList : function() {
if(this.loaded_list == null) {
$this = this;
$this.loaded_list = {};
$('script').each(function() {
if($(this).attr('src')) $this.loaded_list[ $(this).attr('src') ] = 1;
});
$('link[@rel="stylesheet"]').each(function() {
if($(this).attr('href')) $this.loaded_list[ $(this).attr('href') ] = 1;
});
}
},
/**
* Returns true if the given CSS or JS script has already been loaded
*/
isItemLoaded : function(scriptUrl) {
this.initialiseItemLoadedList();
return this.loaded_list[scriptUrl] != undefined;
},
requireJs : function(scriptUrl, callback, opts, obj, scope)
{
if(opts != undefined || opts == null){
$.extend($.requireConfig, opts);
}
var _request = {
url : scriptUrl,
callback : callback,
opts : opts,
obj : obj,
scope : scope
}
if(this.pending)
{
this.queue.push(_request);
return;
}
this.pending = _request;
this.initialiseItemLoadedList();
if (this.loaded_list[this.pending.url] != undefined) { // if required file exists (by PGA)
this.requestComplete(); // => request complete
return;
}
var _this = this;
var _url = (isExternalScript(scriptUrl)) ? scriptUrl : $.requireConfig.routeJs + scriptUrl;
var _head = document.getElementsByTagName('head')[0];
var _scriptTag = document.createElement('script');
// Firefox, Opera
$(_scriptTag).bind('load', function(){
_this.requestComplete();
});
// IE
_scriptTag.onreadystatechange = function(){
if(this.readyState === 'loaded' || this.readyState === 'complete'){
_this.requestComplete();
}
}
_scriptTag.type = "text/javascript";
_scriptTag.src = _url;
_head.appendChild(_scriptTag);
},
requestComplete : function()
{
if(this.pending.callback){
if(this.pending.obj){
if(this.pending.scope){
this.pending.callback.call(this.pending.obj);
} else {
this.pending.callback.call(window, this.pending.obj);
}
} else {
this.pending.callback.call();
}
}
this.loaded_list[this.pending.url] = 1; // adding loaded file to loaded list (by PGA)
this.pending = null;
if(this.queue.length > 0)
{
var request = this.queue.shift();
this.requireJs(request.url, request.callback, request.opts, request.obj, request.scope);
}
},
requireCss : function(styleUrl, media){
if(media == null) media = 'all';
// Don't double up on loading scripts
if(this.isItemLoaded(styleUrl)) return;
if(document.createStyleSheet){
var ss = document.createStyleSheet($.requireConfig.routeCss + styleUrl);
ss.media = media;
} else {
var styleTag = document.createElement('link');
$(styleTag).attr({
href : $.requireConfig.routeCss + styleUrl,
type : 'text/css',
media : media,
rel : 'stylesheet'
}).appendTo($('head').get(0));
}
this.loaded_list[styleUrl] = 1;
}
})
/**
* Sapphire extensions
* Ajax requests are amended to look for X-Include-JS and X-Include-CSS headers
*/
_originalAjax = $.ajax;
$.ajax = function(s) {
var _complete = s.complete;
var _success = s.success;
var _dataType = s.dataType;
// This replaces the usual ajax success & complete handlers. They are called after any on demand JS is loaded.
var _ondemandComplete = function(xml) {
var status = jQuery.httpSuccess(xml) ? 'success' : 'error';
if(status == 'success') {
data = jQuery.httpData(xml, _dataType);
if(_success) _success(data, status, xml);
}
if(_complete) _complete(xml, status);
}
// We remove the success handler and take care of calling it outselves within _ondemandComplete
s.success = null;
s.complete = function(xml, status) {
processOnDemandHeaders(xml, _ondemandComplete);
}
return _originalAjax(s);
}
})(jQuery);
/**
* This is the on-demand handler used by our patched version of prototype.
* once we get rid of all uses of prototype, we can remove this
*/
function prototypeOnDemandHandler(xml, callback) {
processOnDemandHeaders(xml, callback);
}
/**
* Process the X-Include-CSS and X-Include-JS headers provided by the Requirements class
*/
function processOnDemandHeaders(xml, _ondemandComplete) {
var i;
// CSS
if(xml.getResponseHeader('X-Include-CSS')) {
var cssIncludes = xml.getResponseHeader('X-Include-CSS').split(',');
for(i=0;i<cssIncludes.length;i++) {
// Syntax 1: "URL:##:media"
if(cssIncludes[i].match(/^(.*):##:(.*)$/)) {
jQuery.requireCss(RegExp.$1, RegExp.$2);
// Syntax 2: "URL"
} else {
jQuery.requireCss(cssIncludes[i]);
}
}
}
// JavaScript
var newIncludes = [];
if(xml.getResponseHeader('X-Include-JS')) {
var jsIncludes = xml.getResponseHeader('X-Include-JS').split(',');
for(i=0;i<jsIncludes.length;i++) {
if(!jQuery.isItemLoaded(jsIncludes[i])) {
newIncludes.push(jsIncludes[i]);
}
}
}
// We make an array of the includes that are actually new, and attach the callback to the last one
// They are placed in a queue and will be included in order. This means that the callback will
// be able to execute script in the new includes (such as a livequery update)
if(newIncludes.length > 0) {
for(i=0;i<jsIncludes.length;i++) {
jQuery.requireJs(jsIncludes[i], (i == jsIncludes.length-1) ? function() { _ondemandComplete(xml); } : null);
}
// If there aren't any new includes, then we can just call the callbacks ourselves
} else {
_ondemandComplete(xml, status);
}
}