Ext.ns('Rwiki'); Rwiki.AboutDialog = Ext.extend(Ext.Window, { constructor: function() { var self = this; Ext.apply(this, { applyTo: 'about-dialog', width: 400, height: 200, plain: true, modal: true, closeAction: 'hide', items: new Ext.TabPanel({ applyTo: 'hello-tabs', autoTabs: true, activeTab: 0, deferredRender: false, border: false }), buttons: [{ text: 'Close', handler: function() { self.hide(); } }] }); Rwiki.AboutDialog.superclass.constructor.apply(this, arguments); } });