Grid CommandItemTemplate dynamic content lost after AJAX call

[Tom Rasmussen]

I have a RadGrid using a CommandItemTemplate wrapped in an RadAjaxPanel:

<telerik:RadAjaxLoadingPanel ID="RadAjaxLoadingPanel1" runat="server" />
<telerik:RadAjaxPanel ID="RadAjaxPanel1" runat="server" ClientEvents-OnRequestStart="RequestStart" ClientEvents-OnResponseEnd="ResponseEnd" LoadingPanelID="RadAjaxLoadingPanel1">
    <telerik:RadGrid ID="AccountGrid1" runat="server" OnNeedDataSource="AccountGrid1_NeedDataSource"
                    OnSortCommand="AccountGrid1_SortCommand" OnGroupsChanging="AccountGrid1_GroupsChanging" OnColumnCreated="AccountGrid1_ColumnCreated" OnItemCreated="AccountGrid1_ItemCreated"
                    AutoGenerateColumns="true" AllowPaging="true" AllowCustomPaging="true" AllowSorting="true" GroupingEnabled="true"
                    ShowGroupPanel="true" ShowFooter="true" ShowHeader="true">
        <GroupingSettings CaseSensitive="false"  />
        <MasterTableView DataKeyNames="Id,ClientId" ClientDataKeyNames="Id" AllowNaturalSort="false"
         AllowMultiColumnSorting="false" AllowCustomSorting="true" CommandItemDisplay="Top">
            <CommandItemStyle HorizontalAlign="Right" />
            <CommandItemTemplate>
                <asp:LinkButton ID="RefreshLinkButton" runat="server" CommandName="RebindGrid"><%= Navigator.Icon("Refresh", "refresh").ToHtmlImage() %> Refresh</asp:LinkButton>  |
                <telerik:RadComboBox ID="gridStatCombo" runat="server" OnClientSelectedIndexChanged="EnableStatButton" DropDownWidth="250" Visible="false">
                    <Items>
                        <telerik:RadComboBoxItem Text="Select a field to group by" Value="" />

                    </Items>
                </telerik:RadComboBox>
                <telerik:RadComboBox ID="gridStatDateCombo" runat="server" Width="75" Visible="false" Enabled="false">
                    <Items>
                        <telerik:RadComboBoxItem Text="Day" Value="DAY" />
                        <telerik:RadComboBoxItem Text="Month" Value="MONTH" Selected="true" />
                        <telerik:RadComboBoxItem Text="Year" Value="YEAR" />
                    </Items>
                </telerik:RadComboBox>
                <telerik:RadButton ID="gridStatBtn" runat="server" Text="View Statistics" OnClick="Stat_Click" Enabled="false" Visible="false" />  |

                <telerik:RadComboBox ID="gridExportCombo" runat="server" OnClientSelectedIndexChanged="EnableExportButton" DropDownWidth="250">
                    <Items>
                        <telerik:RadComboBoxItem Text="Select an export format" Value="" />
                        <telerik:RadComboBoxItem Text="Excel" Value="Excel" ImageUrl="~/Main/Content/Images/Icons/excel.png" />
                        <telerik:RadComboBoxItem Text="Word" Value="Word" ImageUrl="~/Main/Content/Images/Icons/ms_word_2.png" />
                        <telerik:RadComboBoxItem Text="PDF" Value="PDF" ImageUrl="~/Main/Content/Images/Icons/filetype_pdf.png" />
                        <telerik:RadComboBoxItem Text="Comma Separated Values (CSV)" Value="CSV" ImageUrl="~/Main/Content/Images/Icons/csv_file.png" />
                        <telerik:RadComboBoxItem Text="Tab-delimited" Value="Tab" ImageUrl="~/Main/Content/Images/Icons/txt_file.png" />
                        <telerik:RadComboBoxItem Text="Tab-delimited w/ Quotes" Value="TabQuote" ImageUrl="~/Main/Content/Images/Icons/txt_file.png" />
                    </Items>
                </telerik:RadComboBox>
                <telerik:RadButton ID="gridBtnExport" runat="server" Text="Export" OnClick="Export_Click" Enabled="false" />
            </CommandItemTemplate>
            <PagerStyle AlwaysVisible="true" />
        </MasterTableView>
        <ClientSettings AllowDragToGroup="true" AllowColumnsReorder="true">
            <Selecting AllowRowSelect="true" />
            <ClientEvents OnRowDblClick="ViewAccount" OnGridCreated="ResizeAccountGrid" />
            <Scrolling AllowScroll="true" UseStaticHeaders="true" ScrollHeight="100%" />
        </ClientSettings>
        <GroupingSettings ShowUnGroupButton="true" />
        <FooterStyle HorizontalAlign="Right" />
        <ExportSettings ExportOnlyData="true" HideStructureColumns="true" IgnorePaging="true"/>
    </telerik:RadGrid>

    <telerik:RadScriptBlock ID="AccountGridScriptBlock" runat="server">
        <script type="text/javascript">
            $(window).resize(function () { ResizeAccountGrid(); });

            function ResizeAccountGrid(sender, eventArgs) {
                ResizeGrid($find("<%= AccountGrid1.ClientID %>"));
            }

            function ViewAccount(sender, eventArgs) {
                var accountId = eventArgs.get_gridDataItem().getDataKeyValue("Id");
                ToolClick(null, null, "<%= Navigator.Inquiry() %>" + "?Id=" + accountId, "<%= (int)SiteNavigatorTab.Inquiry %>", false);
            }

            function RequestStart(sender, eventArgs) {
                //Log the start time
                startTime = new Date();
                if (eventArgs.EventTarget.indexOf("gridBtnExport") > 0) {
                    eventArgs.EnableAjax = false;
                }
            }

            function ResponseEnd(sender, eventArgs) {
                //Log the end time
                var endTime = new Date();
                //Display the total time
                //$get("<%= lblTotal.ClientID %>").innerHTML = endTime - startTime + " ms";
            }

            function EnableExportButton(sender, eventArgs) {
                var item = eventArgs.get_item();
                var button = $find('<%= (AccountGrid1.MasterTableView.GetItems(GridItemType.CommandItem)[0]).FindControl("gridBtnExport").ClientID %>');
                var selectedIndex = item.get_index();
                button.set_enabled(selectedIndex != 0);
            }

            function EnableStatButton(sender, eventArgs) {
                var item = eventArgs.get_item();
                var button = $find('<%= (AccountGrid1.MasterTableView.GetItems(GridItemType.CommandItem)[0]).FindControl("gridStatBtn").ClientID %>');
                var dateBreak = $find('<%= (AccountGrid1.MasterTableView.GetItems(GridItemType.CommandItem)[0]).FindControl("gridStatDateCombo").ClientID %>');
                var selectedIndex = item.get_index();
                button.set_enabled(selectedIndex != 0);
                var dateFields = "<%= JsDateTimeFields %>".split("|");
                var text = item.get_text();
                var exists = $.inArray(text, dateFields) > -1;
                dateBreak.set_enabled(exists);
            }
        </script>
    </telerik:RadScriptBlock>
</telerik:RadAjaxPanel>

The RadComboBox (id gridStatCombo) is populated server side in Page_Load:

protected void Page_Load(object sender, EventArgs e)
{
    var gridStatCombo = (RadComboBox)AccountGrid1.MasterTableView.GetItems(GridItemType.CommandItem)[0].FindControl("gridStatCombo");
    var gridStatDateCombo = (RadComboBox)AccountGrid1.MasterTableView.GetItems(GridItemType.CommandItem)[0].FindControl("gridStatDateCombo");
    var gridStatBtn = (RadButton)AccountGrid1.MasterTableView.GetItems(GridItemType.CommandItem)[0].FindControl("gridStatBtn");
    foreach (var fieldName in Configuration[Vars.StatisticalReportFields].Value
        .Split(new[] { ", " }, StringSplitOptions.RemoveEmptyEntries).OrderBy(f => f.Trim()))
    {
        if (!User.ParentCawClient.HasAccountField(fieldName)) continue;
        var field = User.ParentCawClient.GetAccountField(fieldName);
        gridStatCombo.Items.Add(new RadComboBoxItem(field.DisplayName, field.ColumnName));
        if (SqlServerUtils.IsDateTimeSqlType(field.SqlDbType))
            JsDateTimeFields += field.DisplayName + "|";
    }
    if (gridStatCombo.Items.Count > 1)
    {
        gridStatCombo.Visible = true;
        gridStatDateCombo.Visible = true;
        gridStatBtn.Visible = true;
    }
}

This process works great on the initial load of the control.  However, after making any form of Ajax call (sorting, paging, grouping, etc.) the combo box in the command item template is not updated.  The content disappears.  Stepping through the code, I can see that it is executed, but the control does not appear to be updated.  The rest of the grid is updated via the Ajax call though.

What am I missing?

[Pavlina]

Hello Tom,

You can check the forum thread below which elaborates on similar subject and see if it helps:
http://www.telerik.com/community/forums/aspnet-ajax/grid/radcombobox-inside-commanditemtemplate-doesn-t-keep-the-selectedvalue-property-after-grid-rebind.aspx

Kind regards,
Pavlina
the Telerik team

[Tom Rasmussen]

Thanks.  By moving the combo box population and enable/disable code to the grid's PreRender event the information remained after any AJAX postback.