How can I switch to a different ajax on a click of an ASP.NET button server side?

Question

I have a set of tabs in a tab container that I can move between freely by manually clicking on the tabs or by using a javascript; however, what I want to do is to switch between tabs using an ASP.NET serverside button.

So here's the layout. Tab 1 has an ASP.NET Button, which, when clicked, should go to Tab 2 and display the results of a query in a gridview. Here is the onclick code for the ASP.NET Button:

    protected void btnOutstandingTasks_Click(object sender, EventArgs e)
    {
        try
        {
            // Load task list by all outstanding tickets
            SqlDSOutstanding.SelectParameters.Clear();
            SqlDSOutstanding.SelectParameters.Add("1", TypeCode.Int64, "3");

            gvxTaskList.DataSourceID = null;
            gvxTaskList.DataSource = SqlDSOutstanding;
            gvxTaskList.DataBind();
            upnlTaskList.Update();

            DispatchTabs.ActiveTabIndex = DispatchTabs.ActiveTabIndex + 1;   

        }
        catch (Exception ex)
        {

        }
    }

Not sure why its not working, but i imagine someone out there knows how to do it. Appreciate the help!

And here is the client side showing that the tab container is inside an update panel.

        <asp:UpdatePanel ID="upnlDispatch" UpdateMode="Conditional" runat="server">
        <Triggers></Triggers>
        <ContentTemplate>
            <ajaxToolkit:TabContainer ID="DispatchTabs" runat="server" Height="100%" Width="100%" CssClass="Tab" ActiveTabIndex="0">
                <ajaxToolkit:TabPanel ID="tabDashboard" runat="server" HeaderText="Dashboard" Width="100%" Height="100%">
                    <HeaderTemplate>
                        Dashboard
                    </HeaderTemplate>
                    <ContentTemplate>
                        <asp:UpdatePanel ID="upnlDashboard" UpdateMode="Conditional" runat="server">
                            <ContentTemplate>                   

Answer 1

Putting the tab container within an update panel should do the trick. Also, currently your code has a flaw, you don't want to always just add 1 to the ActiveIndex tab because you will get an out of range exception if you go beyond the last one.

if(DispatchTabs.ActiveTabIndex == DispatchTabs.Count() -1)
{
   DispatchTabs.ActiveTabIndex = 0;
}
else
{
   DispatchTabs.ActiveTabIndex = DispatchTabs.ActiveTabIndex + 1;  
}