tabs

<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="tabs.aspx.cs" Inherits="Extjs.tabs" %>
<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server">
<script type="text/javascript">
    Ext.onReady(function () {
        Ext.create("Ext.tab.Panel", {
            300,
            height: 200,
            activeTab: 0,
            defaults:{
                bodyPadding:10,
                autoScroll:true
            },
            items: [{
                title: 'Tab 1',
                html: 'A sample tab'
            },
            {
                title: 'Tab 2',
                loader: {
                    url: 'ajax1.htm',
                    contentType: 'html',
                    loadMask: true,
                },
                listeners: {
                    activate: function (tab) {
                        tab.loader.load();
                    }
                }
            }],
            renderTo: 'tab'
        })
    });
</script>
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
<div id="tab"></div>
</asp:Content>

ajax1.html

I'm am content loaded via AJAX. I was set up using the loader property on my Ext.Panel object:
<div style="padding:10px;background:#f1f1f1;">
<pre>
    loader: {
        url: 'ajax1.htm',
        contentType: 'html',
        loadMask: true
    }
</pre>
</div>
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