/* Source: classbehaviours.ajax.js ClassBehaviours is a javascript framework based on class-name parsing. Copyright 2011 by Maurice van Creij and published on http://www.woollymittens.nl/ This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License. */ // CLASSBEHAVIOURS CLASS // create the root classbehaviours object if it doesn't already exist if(typeof(classBehaviours)=='undefined') classBehaviours = {}; // COMMON AJAX FUNCTIONS // this implementation of AJAX adds a request queue as a differentiating feature if(typeof(classBehaviours.ajax)=='undefined') classBehaviours.ajax = { queue : new Array(), deserializeHTML : function(text){ newElement = document.createElement('DIV'); newElement.innerHTML = text; return newElement; }, deserializeXML : function(text){ if (window.DOMParser){ parser = new DOMParser(); xmlDoc = parser.parseFromString(text,"text/xml"); }else{ xmlDoc = new ActiveXObject("Microsoft.XMLDOM"); xmlDoc.async = "false"; xmlDoc.loadXML(text); } return xmlDoc; }, defaultProgressHandler : function(progressStatus, progressNode, progressError){ // fill the refered node with a progress report progressNode.innerHTML = (progressStatus>-1) ? 'Loading: ' + Math.round(progressStatus * 100) + '%' : 'Error: ' + progressError ; }, defaultLoadHandler : function(loadXml, loadNode, loadText){ // fill the refered node with the returned html string loadNode.innerHTML = loadText.split('')[1].split('')[0]; }, addRequest : function(url, loadHandler, progressHandler, post, referingObject){ // get the first free slot in the que index = this.queue.length; // add new request to the end of the que this.queue[index] = new this.HttpRequest(); // set request constants this.queue[index].idx = index; this.queue[index].url = url; this.queue[index].post = post; this.queue[index].method = (post!=null) ? 'POST' : 'GET' ; // request events this.queue[index].doOnLoad = (loadHandler=='default') ? this.defaultLoadHandler : loadHandler ; this.queue[index].doOnProgress = (progressHandler=='default') ? this.defaultProgressHandler : progressHandler ; this.queue[index].referObject = referingObject; // request properties this.queue[index].time = new Date(); // ask the queue handler to handle the next queued item this.handleQueue(); // return false return false; }, makeRequest : function(queued){ // branch for native XMLHttpRequest object if(window.XMLHttpRequest){ queued.request = new XMLHttpRequest(); queued.request.onreadystatechange = this.progress; queued.request.open(queued.method, queued.url, true); if(queued.method == 'POST'){ queued.request.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); queued.request.setRequestHeader("Content-length", queued.post.length); queued.request.setRequestHeader("Connection", "close"); } queued.request.send(queued.post); // branch for IE/Windows ActiveX version }else if(window.ActiveXObject){ queued.request = new ActiveXObject("Microsoft.XMLHTTP"); queued.request.onreadystatechange = this.progress; queued.request.open(queued.method, queued.url, true); if(queued.method == 'POST'){ queued.request.setRequestHeader("Content-type", "application/x-www-form-urlencoded"); queued.request.setRequestHeader("Content-length", queued.post.length); queued.request.setRequestHeader("Connection", "close"); } queued.request.send(queued.post); // if all else fails: load the document in an iFrame }else if(window.frames){ // create an iframe to read the document in objIframe = document.createElement("IFRAME"); objIframe.src = queued.url; objIframe.id = "feedimport0"; objIframe.name = "feedimport0"; objIframe.style = "visibility : invisible; position : absolute; left : -1600px; top : -1600px;"; //objIframe.onload = ajax_load; // Doesn't work in Opera // append the iframe to the document document.body.appendChild(objIframe); // wait for the iframe to load this.wait(); } }, handleQueue : function(){ queue = classBehaviours.ajax.queue; // if the first item in the queue is a completed request if(queue.length>0){ if(queue[0].ready==4 /*&& ajax.queue[0].status==200*/){ // remove the completed request queue.reverse(); queue.length = queue.length - 1; queue.reverse(); } } // if the first item in the queue isn't allready in progress if(queue.length>0){ if(!(queue[0].ready<4 && queue[0].ready!=null)){ this.makeRequest(queue[0]); } } }, progress : function(){ queued = classBehaviours.ajax.queue[0]; // remember the readyState queued.ready = queued.request.readyState; // only if req shows "complete" if(queued.request.readyState == 4){ // remember the status queued.status = queued.request.status; // only if "OK" if(queued.request.status == 200 || queued.request.status == 304){ // update optional progress indicator code if(queued.doOnProgress) queued.doOnProgress(4, queued.referObject, queued.request.status, queued.time); // get the imported text queued.text = queued.request.responseText; // get the imported document queued.document = queued.request.responseXML; // if the document is empty use a deserialized version of the text instead if(queued.document==null) queued.document = classBehaviours.ajax.deserializeHTML(queued.text) else if(queued.document.childNodes.length==0) queued.document = classBehaviours.ajax.deserializeHTML(queued.text); // trigger the load event if(queued.doOnLoad) queued.doOnLoad(queued.document, queued.referObject, queued.text, queued.time); // request the next item in the queue to be handled classBehaviours.ajax.handleQueue(); }else{ // update optional progress indicator code if(queued.doOnProgress) queued.doOnProgress(-1, queued.referObject, queued.request.status, queued.time); } }else{ // update optional progress indicator code if(queued.doOnProgress) queued.doOnProgress(queued.request.readyState, queued.referObject, 200, queued.time); } // return the status if desired return queued.request.readyState; }, wait : function(){ queued = classBehaviours.ajax.queue[0]; // if the xml document has loaded in the iframe if(window.frames["feedimport0"]){ // define the xml document object queued.document = window.frames["feedimport0"].document; queued.text = window.frames["feedimport0"].document.body.innerHTML; // what to do after the xml document loads queued.doOnLoad(queued.document, queued.referObject, queued.text, queued.time); // else try again in a while }else{ setTimeout("ajax.wait()",256); } }, HttpRequest : function(){ // request constants this.idx = null; this.url = null; this.post = null; this.method = 'GET'; // request events this.doOnLoad = null; this.doOnProgress = null; this.referObject = null; // request properties this.request = null; this.document = null; this.text = null; this.ready = null; this.status = null; this.time = null; } }