/* --- description: A Class that provides a cross-browser history-management functionaility, using the browser hash to store the application's state license: MIT-style authors: - Arieh Glazer - Dave De Vos - Digitarald requires: - core/1.2.4: Class - core/1.2.4: Class.Extras - core/1.2.4: Element provides: [HashListner] ... */ /* * modified by Robert.Schulze@dotless.de : * - return `this` in [[HashListener#start]] and [[HashListener#stop]] for a fluent API * - adding an mechanism, to let async processes (event driven) block und unblock the (real) startup of the lister * - adds an option `pollInterval` for the default 100ms to poll the hash state * - fix some jsLint concerns */ var HashListener = new Class({ Implements : [Options,Events], options : { blank_page : 'blank.html', start : false, pollInterval: 100 }, iframe : null, currentHash : '', firstLoad : true, handle : false, useIframe : (Browser.Engine.trident && (typeof(document.documentMode)=='undefined' || document.documentMode < 8)), ignoreLocationChange : false, startBlockers: null, initialize : function(options){ var s_f, self=this, cached_storage; this.setOptions(options); this.startBlockers = new Hash(); // Disable Opera's fast back/forward navigation mode if (Browser.Engine.presto && window.history.navigationMode) { window.history.navigationMode = 'compatible'; } // IE8 in IE7 mode defines window.onhashchange, but never fires it... if (window.onhashchange && (typeof(document.documentMode) == 'undefined' || document.documentMode > 7)) { // The HTML5 way of handling DHTML history... window.onhashchange = function () { var hash = self.getHash(); if (hash == self.currentHash) { return; } self.fireEvent('hash-changed',hash); }; } else { if (this.useIframe){ this.initializeHistoryIframe(); } } window.addEvent('unload', function(event) { self.firstLoad = null; }); if (this.options.start) this.start(); }, initializeHistoryIframe : function(){ var hash = this.getHash(), self = this, doc; this.iframe = new IFrame({ src : this.options.blank_page, styles : { 'position' : 'absolute', 'top' : 0, 'left' : 0, 'width' : '1px', 'height' : '1px', 'visibility': 'hidden' } }).inject(document.body); doc = (this.iframe.contentDocument) ? this.iframe.contentDocumnet : this.iframe.contentWindow.document; doc.open(); doc.write('' + hash + ''); doc.close(); return; }, checkHash : function(){ var hash = this.getHash(), ie_state, doc; if (this.ignoreLocationChange) { this.ignoreLocationChange = false; return; } if (this.useIframe){ doc = (this.iframe.contentDocument) ? this.iframe.contentDocumnet : this.iframe.contentWindow.document; ie_state = doc.body.innerHTML; if (ie_state!=hash){ this.setHash(ie_state); hash = ie_state; } } if (this.currentLocation == hash) { return; } this.currentLocation = hash; this.fireEvent('hash-changed',hash); }, setHash : function(newHash){ window.location.hash = this.currentLocation = newHash; this.fireEvent('hash-changed',newHash); }, getHash : function(){ var m; if (Browser.Engine.geko){ m = /#(.*)$/.exec(window.location.href); return m && m[1] ? m[1] : ''; }else{ return window.location.hash.substr(1); } }, setIframeHash: function(newHash) { var doc = (this.iframe.contentDocument) ? this.iframe.contentDocumnet : this.iframe.contentWindow.document; doc.open(); doc.write('' + newHash + ''); doc.close(); }, updateHash : function (newHash){ if ($type(document.id(newHash))) { this.debug_msg("Exception: History locations can not have the same value as _any_ IDs that might be in the document," + " due to a bug in IE; please ask the developer to choose a history location that does not match any HTML" + " IDs in this document. The following ID is already taken and cannot be a location: " + newLocation); } this.ignoreLocationChange = true; if (this.useIframe) this.setIframeHash(newHash); else this.setHash(newHash); }, start : function() { this.startupCheck = this.doStart.periodical(this.options.pollInterval, this); return this; }, doStart: function () { if (false === this.isStartBlocked()) { $clear(this.startupCheck); this.handle = this.checkHash.periodical(this.options.pollInterval, this); } }, stop : function(){ $clear(this.handle); return this; }, blockStart: function (forKey) { // prefix, to get not into trubble with reserved words this.startBlockers.set('block:'+forKey, true); }, unblockStart: function (forKey) { // prefix, to get not into trubble with reserved words this.startBlockers.erase('block:'+forKey); }, isStartBlocked: function () { return (0 < this.startBlockers.getLength()); } });