I have ext:FileUploadField on the page. After file upload I need to show a link to this file. I dynamically create a LinkButton, add it on the Panel1, and I can't see the the LinkButton! I dunno why!

<ext:Panel ID="Panel1" runat="server">
    <Content>
        <ext:FileUploadField ID="FileUploadField1" runat="server" EmptyText="Choose a file" FieldLabel="File" Icon="ImageAdd" />
    </Content>
    <Buttons>
        <ext:Button ID="SaveButton2" runat="server" Text="Upload">
            <DirectEvents>
                <Click OnEvent="UploadClick"></Click>
            </DirectEvents>
        </ext:Button>
    </Buttons>
</ext:Panel>


protected void UploadClick(object sender, DirectEventArgs e)
        {
            if (this.FileUploadField1.HasFile)
            {
                var attachment = new Attachment { ............ };
                if (UploadAttachment(attachment))
                {
                    X.Msg.Show( ...... );

                    var linkButton = new LinkButton();
                    linkButton.ID = "fdsfdsfds";
                    linkButton.Text = attachment.Name;
                    linkButton.NavigateUrl = "#";
                    linkButton.Render();
                    Panel1.Add(linkButton);
                    // Panel1.Render(true);
                     Panel1.DoLayout(true,true);
                }
                else
                {
                   //................
                }

            }
            else
            {
                //................
            }
        }