XMLHttpPanel Callback Loading Error...

[Quan Nguyen]

Hi, I try to use RadXMLHttpPanel to load image for each radgrid row during OnRowSelected client event

<ClientEvents OnRowSelected="RowSelected" />. I got this error:
XMLHttpPanel Callback Loading Error:
Exception=The target 'contentControl$RadXmlHttpPanel1' for callback could not be found or did not implement ICallBackEventHandler (screenshot attached). I am following your TELERIK.SALESDASHBOARD demo with some modifications. Below are the source codes that cause this error

.aspx codes:

 

<%@ Control Language="VB" AutoEventWireup="false" CodeFile="BatchDetails.ascx.vb" Inherits="Controls_DocumentInquiry_BatchDetails" %>

<%@ Register Assembly="Telerik.Web.UI" Namespace="Telerik.Web.UI" TagPrefix="telerik" %>

<telerik:RadScriptBlock ID="RadScriptBlock1" runat="server">

 

      <script type="text/javascript">

            function RowSelected(sender, eventArgs)

            {

                  var orderID = sender.get_masterTableView().get_dataItems()[eventArgs.get_itemIndexHierarchical()].getDataKeyValue("BatchNumber");

                  alert(orderID);

                  var oXmlPanel = $find("<%= RadXmlHttpPanel1.ClientID %>");

                  oXmlPanel.set_value(orderID);

            }

           

      </script>

 

</telerik:RadScriptBlock>

 

<div class="batchesContainer">

      <asp:Label runat="server" ID="batchdetailsTitle" CssClass="detailsTitle">Orders for</asp:Label>

      <div class="pageNav">

            <asp:LinkButton runat="server" ID="prevPage" CssClass="prevPage">Previous</asp:LinkButton>

            <asp:LinkButton runat="server" ID="nextPage" CssClass="nextPage">Next</asp:LinkButton>

      </div>

     

   

    <div class="batchDetails">

        <div class="batchdetailsGrid">

            <telerik:RadGrid AllowFilteringByColumn="true" AllowSorting="true" ShowGroupPanel="false" Height="300px" BackColor="#393939"

            ID="rgBatchDetails" runat="server" AllowPaging="true" PageSize="10" Width="480px"

            OnPreRender="rgBatchDetails_PreRender" OnNeedDataSource="rgBatchDetails_NeedDataSource" OnSelectedIndexChanged="rgBatchDetails_SelectedIndexChanged" >

                <ClientSettings AllowDragToGroup="true" EnableRowHoverStyle="true">

                        <Selecting AllowRowSelect="true" />

                        <ClientEvents OnRowSelected="RowSelected" />

                  </ClientSettings>

                <MasterTableView AutoGenerateColumns="false" PagerStyle-Mode="NextPrevAndNumeric" ClientDataKeyNames="BatchNumber,ImageFile"         

                        TableLayout="Fixed">

                    <Columns>

                        <telerik:GridBoundColumn DataField="BatchNumber" HeaderText="Batch Number" AutoPostBackOnFilter="true" ShowFilterIcon="false" HeaderStyle-Width="60px"  FilterControlWidth="35px">

                              </telerik:GridBoundColumn>

                              <telerik:GridNumericColumn DataField="ImageFile" HeaderText="Image File" AutoPostBackOnFilter="true" ShowFilterIcon="false" HeaderStyle-Width="60px"  FilterControlWidth="35px">

                              </telerik:GridNumericColumn>

                              <telerik:GridBoundColumn DataField="MICRValue" HeaderText="MICR/OCR" HeaderStyle-Width="300px" FilterControlWidth="260px">

                              </telerik:GridBoundColumn>         

                              <telerik:GridBoundColumn DataField="Amount" HeaderText="Amount" FilterControlWidth="70px">

                              </telerik:GridBoundColumn>

                          </Columns>

 

                </MasterTableView>

            </telerik:RadGrid>

        </div>

        <div class="batchdetailsImage">

            <telerik:RadXmlHttpPanel ID="RadXmlHttpPanel1" runat="server" OnServiceRequest="RadXmlHttpPanel1_ServiceRequest" RenderMode="Block">

                    <asp:Image ID="imgDocumentImage" runat="server" Height="300px" Width="500px"/>

              </telerik:RadXmlHttpPanel>

        </div>

    </div>

    <telerik:RadAjaxLoadingPanel ID="BatchesLoadingPanel" runat="server"></telerik:RadAjaxLoadingPanel>

</div>

.vb codes:
When I click a TreeNode (LoadOnDemand: TreeNodeExpandMode.ServerSideCallBack)  on the main aspx page, it would load this control.

Imports

 

Telerik.Web.UI

 

Imports

 

System

 

Imports

 

System.Linq

 

Imports

 

System.Linq.Expressions

 

Imports

 

System.Web.UI

 

Imports

 

System.Data

 

Partial

 

Class Controls_DocumentInquiry_BatchDetails

 

 

Inherits ContentControl

 

    Protected Sub RadXmlHttpPanel1_ServiceRequest(ByVal source As Object, ByVal e As RadXmlHttpPanelEventArgs) Handles RadXmlHttpPanel1.ServiceRequest

        Dim BatchNumber = e.Value.ToString

        imgDocumentImage.ImageUrl = "Image.aspx?ImageLocation=00000481.TIF"

    End Sub

 

Protected

 

Sub Page_PreRender(ByVal sender As Object, ByVal e As EventArgs)

 

 

Dim ajaxManager As RadAjaxManager = RadAjaxManager.GetCurrent(Page)

 

ajaxManager.AjaxSettings.AddAjaxSetting(rgBatchDetails, rgBatchDetails, BatchesLoadingPanel)

 

End Sub

 

 

Protected Sub rgBatchDetails_PreRender(ByVal sender As Object, ByVal e As EventArgs)

 

 

If rgBatchDetails.MasterTableView.Items.Count > 0 And rgBatchDetails.SelectedItems.Count = 0 Then

 

rgBatchDetails.MasterTableView.Items(0).Selected =

True

 

 

End If

 

 

End Sub

 

 

Protected Sub rgBatchDetails_NeedDataSource(ByVal source As Object, ByVal e As GridNeedDataSourceEventArgs)

 

 

If Session("dsBatchData") Is Nothing Then

 

 

Else

 

rgBatchDetails.DataSource = Session(

"dsBatchData")

 

 

End If

 

 

End Sub

 

Thank you
Quan

[Pero]

Hello Quan,

Thank you for the source code. I tested it after a couple of modifications, but did not experience any problems. Could you please send the source code that adds the UserControl to the page? I have attached the sample project that I tested to the thread.

Kind regards,
Pero
the Telerik team

[Quan Nguyen]

THank you. I got this working by using loading control in Page_Load of the main aspx.

 

[Pero]

Hi Quan,

I am glad that you resolved the problems, and everything is working fine now. Please take into consideration, when working with the XmlHttpPanel, the page does not go through its full page lifecycle. There is no ViewState, the server-side events does not get executed, and the control tree is not recreated. That's why the XmlHttpPanel does not support many of the scenarios that are easily implemented with the Ajax panel.

More information about the RadXmlHttpPanel control can be found on our online documentation: http://www.telerik.com/help/aspnet-ajax/radxmlhttppanel-getting-started.html.

Sincerely yours,
Pero
the Telerik team

[Francis Frank]

Please Team,

I want to bring to your notice that RadXmlHttp control does not support controls like Combo, Button or Textbox.
when tried gives  a call back loading error

[Pero]

Hello Frank,

Could you please be more specific, what kind of callback errors do you get? I created a simple application to test for a problem, but did not experience any errors. The XmlHttpPanel has RadComboBox, Button and TextBox controls, that are updated with the XmlHttpPanel.
Please find the code attached to the thread.

All the best,
Pero
the Telerik team

[Francis Frank]

sorry for my delayed responce.

Thanks for the attached code but i do not know why my code was giving me that error.
I had to use ajax instead of xmlhttp.
I hope i find it convinient to try again.
Thanks for ur responce