Javascript error - why cant JS find a Ext control? "<Window> is not defined"

[wagger]

I want that Javascript should hide a Window.

In my real project, it is not working. So I thought that I make a dummy with the same code approximately so that there was something easy that someone could copy-paste to try out and test. However, the dummy works as expected and its as almost exactly the same code.

So, my not-working page I will present here. The working version, "Test.aspx" follows below.

NOT WORKING VERSION:
__________________________

Part of Customers.aspx:

<%@ Page Title="" Language="C#" MasterPageFile="~/Secure/Views/View.Master" AutoEventWireup="true" CodeBehind="Customers.aspx.cs" Inherits="WebApplicationExtNetTest.Secure.Views.Customers" %>
<%@ Register Assembly="Ext.Net" Namespace="Ext.Net" TagPrefix="ext" %>
<%@ Register TagPrefix="CP" TagName="Customer" Src="../UserControls/Customer.ascx" %>

<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="server">
<script language="javascript" type="text/javascript">

    function CustomerReportCallback(success, errorMsg, customerId) {
        alert("Test: " + customerId);   // this alert shows!
        Window_CreateNewCustomer.hide();  // Here we get an error saying "Uncaught ReferenceError: Window_CreateNewCustomer is not defined"
    }
</script>
</asp:Content>
// cut away some stuff

<asp:Content ID="Content3" ContentPlaceHolderID="CPH_west" runat="server">
    <ext:Container ID="Container1" runat="server" Layout="Fit" Height="800" MonitorResize="true">
        <Content>
              // Some stuff
              
              // Nested here somewhere I have a GridPanel and on that a button that shows the Window below as follows:
              <ext:GridPanel
                        ID="GridPanel2" 
                        runat="server" 
                        StoreID="Store_AvailableCustomers">
                            <TopBar>
                                <ext:Toolbar runat="server">
                                    <Items>
                                        <ext:Button ID="btnCreateNewCustomer" runat="server" Icon="Add" Text="Skapa ny kund">
                                            <DirectEvents>
                                                <Click OnEvent="Button_ShowCreateNewCustomer_Click">
                                                    <EventMask ShowMask="true" />
                                                </Click>
                                            </DirectEvents> 
                                        </ext:Button>
                                    </Items>
                                </ext:Toolbar>
                            </TopBar>
              // more stuff

              <ext:Window 
                          ID="Window_CreateNewCustomer" 
                          runat="server" 
                          Icon="New"
                          Title="Skapa ny kund" 
                          Hidden="true"
                          Width="480"
                          Height="370"
                          Modal="true">

                          <Content>
                              <CP:Customer ID="customer_create" runat="server" Title="Skapa ny kund"  />
                          </Content>
                  </ext:Window>
        </Content>
    </ext:Container>
</asp:Content>

The UserControl "Customer" in the Window has a button that calls a DirectMethod, and in that DirectMethod we call some stuff that eventually finds its way to the javascript on top, but fails there saying "Uncaught ReferenceError: Window_CreateNewCustomer is not defined".

We know that the javascript function is called since we get the first alert saying "Test: "...

The only difference I can see between the two is that above we call a code-behind method, DirectEvent, that shows the Windows:

 
protected void Button_ShowCreateNewCustomer_Click(object sender, DirectEventArgs e)
{
     customer_create._CustomerId = 0;
     Window_CreateNewCustomer.Show();
}

while below it is done like:

<Click Handler="Window_CreateNewCustomer.show()" />

Actually, when changing the above code to use a Listener instead of DirectEvent, the Window won't show at all:

<ext:Button ID="btnCreateNewCustomer" runat="server" Icon="Add" Text="Skapa ny kund">
    <Listeners>
        <Click Handler="Window_CreateNewCustomer.show()" />
    </Listeners>
</ext:Button>

Whats going on?


WORKING VERSION:
__________________________

<%@ Page Language="C#" %>
<%@ Register assembly="Ext.Net" namespace="Ext.Net" tagprefix="ext" %>

<script runat="server">
    [DirectMethod]
    public void CreateNewCustomer()
    {
        X.Js.Call("CustomerReportCallback", 1, "", 123);
    }
</script>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head id="Head1" runat="server">
    <title>Show a Hidden Window - Ext.NET Examples</title>
    <link href="../../../../resources/css/examples.css" rel="stylesheet" type="text/css" />

    <script language="javascript" type="text/javascript">

        function CustomerReportCallback(success, errorMsg, customerId) {
            alert("Test: " + customerId);
            Window_CreateNewCustomer.hide();
        }
    </script>
</head>
<body>
    <form id="Form1" runat="server">
        <ext:ResourceManager ID="ResourceManager1" runat="server">
          
        </ext:ResourceManager>
        
       <ext:Button 
                ID="Button3" 
                runat="server" 
                Text="Click Listener">
                <Listeners>
                    <Click Handler="Window_CreateNewCustomer.show()" />
                </Listeners>
            </ext:Button>

            <ext:Window 
        ID="Window_CreateNewCustomer" 
        runat="server" 
        Icon="New"
        Title="Skapa ny kund" 
        Hidden="true">

        <Content>
            <ext:FormPanel ID="FormPanel2" runat="server" Height="330"  Width="460" Title="Kundinformation" Padding="5" MonitorResize="true">
                <BottomBar runat="server">
                    <ext:Toolbar ID="Toolbar2" runat="server">
                        <Items>
                            <ext:ToolbarFill ID="ToolbarFill2" runat="server" />
                            <ext:Button ID="Button2" Icon="Disk" Text="Spara" runat="server" >
                             <Listeners>
                                <Click Handler="Ext.net.DirectMethods.CreateNewCustomer()" />
                            </Listeners>
                            </ext:Button>
                        </Items>
                    </ext:Toolbar>
                </BottomBar>
                <Content>
                    <ext:FieldSet ID="FieldSet1"
                    runat="server"
                    Title="Grunddata"
                    AutoHeight="true"
                    Layout="Form">
                        <Items>
                            <ext:CompositeField ID="CompositeField9" runat="server" FieldLabel="Personnr" AnchorHorizontal="100%">
                                <Items>
                                    <ext:TextField ID="TextField1" runat="server" Width="220" />
                                </Items>
                            </ext:CompositeField>
                        </Items>
                    </ext:FieldSet>
                </Content>
            </ext:FormPanel>
        </Content>
    </ext:Window>
    </form>
</body>
</html>