This is a migrated thread and some comments may be shown as answers.

Callback the first time, postbacks after that...

18 Answers 548 Views

Ajax

This is a migrated thread and some comments may be shown as answers.

Jason Maronge asked on 25 Apr 2007, 02:07 PM

I am on my way to having my first "Prometheus" ajax page. I switched out the RadAjaxPanel, LoadingPanel, added the RadCodeBlock to my JS section and the ScriptManager to the top of the page. Now when I click a button on the page it does the ajax callback fine, but when I click it again it does a postback and does a postback any time thereafter. It seems that only the first time a postback is performed does it do the callback.

    <asp:ScriptManager ID="ScriptManager1" runat="server" EnablePartialRendering="true">  

    </asp:ScriptManager> 

    <telerik:RadCodeBlock ID="cb" runat="server">  

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

        window.CalendarChanged = function(calendarInstance, args)  

        {  

            if (args.RenderDay.IsSelected)   

                return false;   

        }  

        window.GetTodaysDateSCH = function(){GetDateStamp(<%=this.txtDate.ClientID %>);}  

        </script> 

    </telerik:RadCodeBlock> 

    <telerik:RadAjaxLoadingPanel ID="alp" runat="server" IsSticky="true" MinDisplayTime="0" 

        HorizontalAlign="Center">  

        <asp:Image ID="Image2" runat="server" alt="loading..." ImageUrl="~/Images/Loading2.gif" /> 

    </telerik:RadAjaxLoadingPanel> 

    <telerik:RadAjaxPanel ID="RadAjaxPanel1" runat="server" LoadingPanelID="alp" EnableAJAX="true" 

        EnableHistory="true" EnablePageHeadUpdate="true">  

        <table> 

            <tr> 

                <td> 

                    <asp:Label ID="title" runat="server" Text="Schedule Search: " /> 

                    <radCln:RadDatePicker ID="txtDate" runat="server" SharedCalendarID="RadCalendar1" 

                        onkeypress="GetTodaysDateSCH();" MinDate="1/1/2000" OnSelectedDateChanged="txtDate_SelectedDateChanged">  

                        <DateInput Title="" ToolTip="Press 'd' for current date" AutoPostBack="true" UseEmbeddedScripts="false" 

                            DateFormat="MM/dd/yyyy">  

                        </DateInput> 

                    </radCln:RadDatePicker> 

                    <radCln:RadCalendar ID="RadCalendar1" runat="server" Skin="WebBlue" UseEmbeddedScripts="false">  

                        <ClientEvents OnDateClick="CalendarChanged" /> 

                    </radCln:RadCalendar> 

                    <asp:Button ID="cmdRefresh" runat="server" Text="Refresh" OnClick="cmdRefresh_Click" /> 

                </td> 

            </tr> 

        </table> 

        <radG:RadGrid ID="rg" runat="server" Style="width: 100%;" AutoGenerateColumns="False" 

            AllowSorting="True" GridLines="None" OnItemDataBound="rg_ItemDataBound" OnNeedDataSource="rg_NeedDataSource">  

            <MasterTableView GridLines="None">  

                <Columns> 

                    <radG:GridBoundColumn DataField="ID" ReadOnly="True" UniqueName="ID" Visible="False">  

                    </radG:GridBoundColumn> 

                    <radG:GridBoundColumn DataField="PatientEncounter_ID" ReadOnly="True" UniqueName="PatientEncounter_ID" 

                        Visible="False">  

                    </radG:GridBoundColumn> 

                    <radG:GridBoundColumn HeaderText="Time" UniqueName="Time" DataField="Time">  

                    </radG:GridBoundColumn> 

                    <radG:GridTemplateColumn HeaderText="Patient" UniqueName="patient" Groupable="False">  

                        <ItemTemplate> 

                            <asp:HyperLink ID="hlp" runat="server" Text='<%# DataBinder.Eval( Container, "DataItem.Patient") %>'></asp:HyperLink> 

                        </ItemTemplate> 

                    </radG:GridTemplateColumn> 

                    <radG:GridBoundColumn HeaderText="Account Number" UniqueName="AccountNumber" DataField="AccountNumber">  

                    </radG:GridBoundColumn> 

                    <radG:GridBoundColumn HeaderText="Procedure" UniqueName="ProcedureName" DataField="ProcedureName">  

                    </radG:GridBoundColumn> 

                    <radG:GridTemplateColumn UniqueName="TemplateColumnAdditionalProcedure" Groupable="False">  

                        <ItemTemplate> 

                            <asp:HyperLink ID="hl" runat="server" ImageUrl="~/Images/MedicalChart.gif"></asp:HyperLink> 

                        </ItemTemplate> 

                    </radG:GridTemplateColumn> 

                </Columns> 

            </MasterTableView> 

            <AlternatingItemStyle BackColor="#ECECEC" /> 

        </radG:RadGrid> 

    </telerik:RadAjaxPanel>

Thanks... Jason

18 Answers, 1 is accepted

answered on 25 Apr 2007, 03:35 PM

WebSite.zip

Hello Jason,

We tried to replicate this however everything seems to work fine. You can find an example application attached.

All the best,
Vlad
the telerik team

Instantly find answers to your questions at the new Telerik Support Center

answered on 08 May 2007, 04:30 PM

This is interesting, because I cam getting the -exact- opposite results.

When I did my first page using Prometheus, everything on my first ajax callback worked fine, as soon as I do my 2nd ajax request, in my browerser I get a javascript alert with the following text:

"Invalid postback or callback argument. Event validation is enabled using <pages enableEventValidation="true"/> in configuration or <%@ Pages EnableEventValidation="true" %> in a page. For security purposes, this feature verifies that arguments to postback or callback events originate from the server control that originally rendered them. If the data is valid and expected, use the ClientScriptManage.RegisterForEventsValidation method in order t register the postback or callback data for validation."

That alert pops up every time after the first ajax request. If I set enableeventvalidation to false in my page directive for the page, everything appears to work exactly how I expect. But I don;t believe i should be turning off event validation.

answered on 04 Aug 2007, 01:41 PM

Telerik.Web.UI_2007_1_731_trial_hotfix.zip

Hi Jason,

Prometheus Futures has been released at the beginning of July (7.05), but you will find attached the latest trial hotfix, which includes another postback issue fix as well.

One can find Prometheus Futures Online Demos here:

http://www.telerik.com/demos/aspnet/prometheus-futures/Ajax/Examples/Overview/DefaultCS.aspx

All the best,
Konstantin Petkov
the Telerik team

Instantly find answers to your questions at the new Telerik Support Center