/** * @class Ext.util.History * * History management component that allows you to register arbitrary tokens that signify application * history state on navigation actions. You can then handle the history {@link #change} event in order * to reset your application UI to the appropriate state when the user navigates forward or backward through * the browser history stack. * * ## Initializing * The {@link #init} method of the History object must be called before using History. This sets up the internal * state and must be the first thing called before using History. * * ## Setup * The History objects requires elements on the page to keep track of the browser history. For older versions of IE, * an IFrame is required to do the tracking. For other browsers, a hidden field can be used. The history objects expects * these to be on the page before the {@link #init} method is called. The following markup is suggested in order * to support all browsers: * * <form id="history-form" class="x-hide-display"> * <input type="hidden" id="x-history-field" /> * <iframe id="x-history-frame"></iframe> * </form> * * @singleton */ Ext.define('Ext.util.History', { singleton: true, alternateClassName: 'Ext.History', mixins: { observable: 'Ext.util.Observable' }, constructor: function() { var me = this; me.oldIEMode = Ext.isIE6 || Ext.isIE7 || !Ext.isStrict && Ext.isIE8; me.iframe = null; me.hiddenField = null; me.ready = false; me.currentToken = null; }, getHash: function() { var href = window.location.href, i = href.indexOf("#"); return i >= 0 ? href.substr(i + 1) : null; }, doSave: function() { this.hiddenField.value = this.currentToken; }, handleStateChange: function(token) { this.currentToken = token; this.fireEvent('change', token); }, updateIFrame: function(token) { var html = '<html><body><div id="state">' + Ext.util.Format.htmlEncode(token) + '</div></body></html>'; try { var doc = this.iframe.contentWindow.document; doc.open(); doc.write(html); doc.close(); return true; } catch (e) { return false; } }, checkIFrame: function () { var me = this, contentWindow = me.iframe.contentWindow; if (!contentWindow || !contentWindow.document) { Ext.Function.defer(this.checkIFrame, 10, this); return; } var doc = contentWindow.document, elem = doc.getElementById("state"), oldToken = elem ? elem.innerText : null, oldHash = me.getHash(); Ext.TaskManager.start({ run: function () { var doc = contentWindow.document, elem = doc.getElementById("state"), newToken = elem ? elem.innerText : null, newHash = me.getHash(); if (newToken !== oldToken) { oldToken = newToken; me.handleStateChange(newToken); window.top.location.hash = newToken; oldHash = newToken; me.doSave(); } else if (newHash !== oldHash) { oldHash = newHash; me.updateIFrame(newHash); } }, interval: 50, scope: me }); me.ready = true; me.fireEvent('ready', me); }, startUp: function () { var me = this; me.currentToken = me.hiddenField.value || this.getHash(); if (me.oldIEMode) { me.checkIFrame(); } else { var hash = me.getHash(); Ext.TaskManager.start({ run: function () { var newHash = me.getHash(); if (newHash !== hash) { hash = newHash; me.handleStateChange(hash); me.doSave(); } }, interval: 50, scope: me }); me.ready = true; me.fireEvent('ready', me); } }, /** * The id of the hidden field required for storing the current history token. * @type String * @property */ fieldId: Ext.baseCSSPrefix + 'history-field', /** * The id of the iframe required by IE to manage the history stack. * @type String * @property */ iframeId: Ext.baseCSSPrefix + 'history-frame', /** * Initialize the global History instance. * @param {Boolean} onReady (optional) A callback function that will be called once the history * component is fully initialized. * @param {Object} scope (optional) The scope (`this` reference) in which the callback is executed. Defaults to the browser window. */ init: function (onReady, scope) { var me = this; if (me.ready) { Ext.callback(onReady, scope, [me]); return; } if (!Ext.isReady) { Ext.onReady(function() { me.init(onReady, scope); }); return; } me.hiddenField = Ext.getDom(me.fieldId); if (me.oldIEMode) { me.iframe = Ext.getDom(me.iframeId); } me.addEvents( /** * @event ready * Fires when the Ext.util.History singleton has been initialized and is ready for use. * @param {Ext.util.History} The Ext.util.History singleton. */ 'ready', /** * @event change * Fires when navigation back or forwards within the local page's history occurs. * @param {String} token An identifier associated with the page state at that point in its history. */ 'change' ); if (onReady) { me.on('ready', onReady, scope, {single: true}); } me.startUp(); }, /** * Add a new token to the history stack. This can be any arbitrary value, although it would * commonly be the concatenation of a component id and another id marking the specific history * state of that component. Example usage: * * // Handle tab changes on a TabPanel * tabPanel.on('tabchange', function(tabPanel, tab){ * Ext.History.add(tabPanel.id + ':' + tab.id); * }); * * @param {String} token The value that defines a particular application-specific history state * @param {Boolean} [preventDuplicates=true] When true, if the passed token matches the current token * it will not save a new history step. Set to false if the same state can be saved more than once * at the same history stack location. */ add: function (token, preventDup) { var me = this; if (preventDup !== false) { if (me.getToken() === token) { return true; } } if (me.oldIEMode) { return me.updateIFrame(token); } else { window.top.location.hash = token; return true; } }, /** * Programmatically steps back one step in browser history (equivalent to the user pressing the Back button). */ back: function() { window.history.go(-1); }, /** * Programmatically steps forward one step in browser history (equivalent to the user pressing the Forward button). */ forward: function(){ window.history.go(1); }, /** * Retrieves the currently-active history token. * @return {String} The token */ getToken: function() { return this.ready ? this.currentToken : this.getHash(); } });