/** * 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. */Ext.define('Ext.util.History', { singleton: true, alternateClassName: 'Ext.History', mixins: { observable: 'Ext.util.Observable' }, /** * @property * True to use `window.top.location.hash` or false to use `window.location.hash`. Must be set before {@link #init} is called * because the `hashchange` event listener is added to the window at initialization time. */ useTopWindow: false, /** * @property {String} currentToken The current token. * @private */ /** * @event ready * Fires when the Ext.util.History singleton has been initialized and is ready for use. * @param {Ext.util.History} history The Ext.util.History singleton. */ /** * @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. */ constructor: function() { var me = this; me.hiddenField = null; me.ready = false; me.currentToken = null; me.mixins.observable.constructor.call(me); }, /** * Gets the actual hash from the url. This shouldn't need to be used directly but use the * {@link #getToken} method instead. * * @return {String} The hash from the window object. * @private */ getHash: function() { return this.win.location.hash.substr(1); }, /** * Updates the hash on the window. This shouldn't need to be used directly but use the * {@link #add} method instead. * * @param {String} hash The hash to use * @private */ setHash: function(hash) { try { this.win.location.hash = hash; this.currentToken = hash; } catch (e) { // IE can give Access Denied (esp. in popup windows) } }, /** * Handles when the hash in the URL has been updated. Will also fired the change event. * * @param {String} token The token that was changed to * @private */ handleStateChange: function(token) { this.currentToken = token; this.fireEvent('change', token); }, /** * Bootstraps the initialization the location.hash. * This will setup the {@link Ext.TaskManager} to poll for hash changes every 50ms. * @private */ startUp: function() { var me = this; me.currentToken = me.getHash(); if (Ext.supports.Hashchange) { Ext.get(me.win).on('hashchange', me.onHashChange, me); } else { Ext.TaskManager.start({ fireIdleEvent: false, run: me.onHashChange, interval: 50, scope: me }); } me.ready = true; me.fireEvent('ready', me); }, onHashChange: function () { var me = this, newHash = me.getHash(); if (newHash !== me.hash) { me.hash = newHash; me.handleStateChange(newHash); } }, /** * Initializes the global History instance. * @param {Function} [onReady] A callback function that will be called once the history * component is fully initialized. * @param {Object} [scope] 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.onInternalReady(function() { me.init(onReady, scope); }); return; } me.win = me.useTopWindow ? window.top : window; me.hash = me.getHash(); 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, preventDuplicates) { var me = this, set = false; if (preventDuplicates === false || me.getToken() !== token) { me.setHash(token); set = true; } return set; }, /** * Programmatically steps back one step in browser history (equivalent to the user pressing the Back button). */ back: function() { var win = this.useTopWindow ? window.top : window; win.history.go(-1); }, /** * Programmatically steps forward one step in browser history (equivalent to the user pressing the Forward button). */ forward: function(){ var win = this.useTopWindow ? window.top : window; win.history.go(1); }, /** * Retrieves the currently-active history token. * @return {String} The token */ getToken: function() { return this.ready ? this.currentToken : this.getHash(); }});