How to close radwindow manager form server side button click

Question

Hi all I have designed a radwindow manager which will have a dropdown and a textbox and a button which are placed inside a update panel.

Every thing works fine but on button click I am closing my window manager as follows

RadWindowManager1.Windows[0].VisibleOnPageLoad = false;

But this didn't work can some one help me this is my design and code

<telerik:RadWindowManager ID="RadWindowManager1" runat="server" Behavior="Default"
        InitialBehavior="None">
        <Windows>
            <telerik:RadWindow ID="RadWindow1" runat="server" Behaviors="Default" InitialBehaviors="None"
                OpenerElementID="btn" Width="650" Height="480" VisibleOnPageLoad="false">                    
                <ContentTemplate>
                    <asp:UpdatePanel ID="up" runat="server" OnUnload="up_Unload">
                    <Triggers>
                    <asp:AsyncPostBackTrigger ControlID="rdcmb" EventName="SelectedIndexChanged" />
                    <asp:AsyncPostBackTrigger ControlID="radbtn" EventName="Click" />
                    </Triggers>
                        <ContentTemplate>
                            <telerik:RadComboBox ID="rdcmb" runat="server" AutoPostBack="true" OnSelectedIndexChanged="sel">
                                <Items>
                                    <telerik:RadComboBoxItem Text="One" Value="One" />
                                    <telerik:RadComboBoxItem Text="Two" Value="Two" />
                                    <telerik:RadComboBoxItem Text="Three" Value="Three" />
                                    <telerik:RadComboBoxItem Text="Four" Value="Four" />
                                </Items>
                            </telerik:RadComboBox>
                            <telerik:RadTextBox ID="rdText" runat="server">
                            </telerik:RadTextBox>
                            <telerik:RadButton ID="radbtn" runat="server" Text="Save" OnClick="btn_Click">
                            </telerik:RadButton>
                        </ContentTemplate>
                    </asp:UpdatePanel>
                </ContentTemplate>
            </telerik:RadWindow>
        </Windows>
    </telerik:RadWindowManager>
    <telerik:RadButton ID="rdbtnwhAnother" Text="Add WithHolding" runat="server" ButtonType="LinkButton"
        OnClick="rdbtnwhAnother_Click">
    </telerik:RadButton>

Code

protected void Page_Load(object sender, EventArgs e)
{
    if (!IsPostBack)
    {
        RadWindowManager1.Windows[0].VisibleOnPageLoad = false;
    }
}

protected void rdbtnwhAnother_Click(object sender, EventArgs e)
{
    RadWindowManager1.Windows[0].VisibleOnPageLoad = true;
}

protected void btn_Click(object sender, EventArgs e)
{
    RadWindowManager1.Windows[0].VisibleOnPageLoad = false;
}

protected void sel(object sender, EventArgs e)
{
    rdText.Text = rdcmb.SelectedItem.Text;
}

protected void up_Unload(object sender, EventArgs e)
{
    /* Cast sender as an updatePanel, and use reflection to invoke * * the page's scriptmanger registerUpdatePanel() method * * */
    //RadWindowManager1.Windows[0].VisibleOnPageLoad = false;
    UpdatePanel aUpdatePanel = sender as UpdatePanel;

    MethodInfo m = (
        from methods in typeof(ScriptManager).GetMethods(
            BindingFlags.NonPublic | BindingFlags.Instance
            )
        where methods.Name.Equals("System.Web.UI.IScriptManagerInternal.RegisterUpdatePanel")
        select methods).First<MethodInfo>();

    m.Invoke(ScriptManager.GetCurrent(aUpdatePanel.Page), new object[] { aUpdatePanel });
}

Answer 1

<script type="text/javascript">

   function getRadWindow() {
      var oWindow = null;
      if (window.radWindow) oWindow = window.radWindow;
      else if (window.frameElement.radWindow) oWindow = window.frameElement.radWindow;
      return oWindow;
   }

   function clientClose(arg) {   
      getRadWindow().close(arg);
   }

</script>

<telerik:RadButton ID="radbtn" runat="server" Text="Save" OnClick="btn_Click">
</telerik:RadButton>

protected void btn_Click(object sender, EventArgs e)
{         
   string script = "clientClose('');"; 

   ScriptManager.RegisterStartupScript(Page, typeof(Page), 
      "closeScript", script, true);
}