ASPxLoadingPanel + ASPxCallback


<asp:Content ID="Content2" ContentPlaceHolderID="phContent" runat="Server">
     <dxcb:ASPxCallback ID="ASPxCallback1" runat="server" ClientInstanceName="Callback">
         <ClientSideEvents CallbackComplete="function(s, e) { LoadingPanel.Hide(); }" />
     </dxcb:ASPxCallback>

     <dxe:ASPxCheckBox ID="ASPxCheckBox1" runat="server" AutoPostBack="true" Checked="True"
         Text="Display the ASPxLoadingPanel over a specific control">
     </dxe:ASPxCheckBox>
     <br />
     <div style="padding: 0px 100px;">
         <table style="width: 100%;"><tr><td id="Panel" align="center" valign="middle" class="Panel">
             <dxe:ASPxButton ID="ASPxButton1" runat="server" Text="Show Loading Panel" AutoPostBack="False">
                 <ClientSideEvents Click="function(s, e) {
     Callback.PerformCallback();
     LoadingPanel.Show();

 }"
                     />
             </dxe:ASPxButton>
         </td></tr></table>
     </div>
     <dxlp:ASPxLoadingPanel ID="LoadingPanel" runat="server" ClientInstanceName="LoadingPanel" Modal="True">
     </dxlp:ASPxLoadingPanel>

 </asp:Content>