RadCombo will not load in updatepanel unless user type in a searcch string

[Quynh]

Hi, I have this Radcombo with checkbox itemtemplate,  without any update panel it works perfectly as I wanted.
But if I add the update pannels in it won't load anymore unless user type in something on the radcombox box
Is there anyway to work around this. I need it to load without have to wait for user to type in a search string
and I also need the loadondemand because it is a huge amount of data to load to the radcombo
Thanks,
Quynh
Default.aspx
<%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true"

    CodeBehind="Default.aspx.cs" Inherits="RadCombo._Default" %>

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

<asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent">

    <style type="text/css">

        table

        {

            border-collapse: collapse;

        }

        table tr, td

        {

            padding: 3px;

        }

    </style>

</asp:Content>

<asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent">

    <telerik:RadScriptManager ID="RadScriptManager1" runat="server">

    </telerik:RadScriptManager>

    <asp:ObjectDataSource ID="PatientDS" runat="server" SelectMethod="GetPatient" 

        TypeName="RadCombo.DB"  >

                                <SelectParameters>

                                    <asp:ControlParameter Name="Study" ControlID="ddlStudy" Type="String" DefaultValue="%" />

                                    <asp:ControlParameter Name="Site" ControlID="ddlSite" Type="String" DefaultValue="%" />

                                </SelectParameters>

                            </asp:ObjectDataSource>

      

    <div>

          

          

        <table>

            <tr>

                <td>

                    Study

                </td>

                <td>

                    <asp:DropDownList ID="ddlStudy" runat="server" Width="500px" AutoPostBack="true"

                        OnSelectedIndexChanged="ddlStudy_SelectedIndexChanged">

                    </asp:DropDownList>

                </td>

            </tr>

            <tr>

                <td>

                    Site

                </td>

                <td>

                    <asp:UpdatePanel ID="updatePanel1" runat="server">

                        <Triggers>

                            <asp:AsyncPostBackTrigger ControlID="ddlStudy" EventName="SelectedIndexChanged" />

                        </Triggers>

                        <ContentTemplate>

                            <asp:DropDownList ID="ddlSite" runat="server" Width="500px" AutoPostBack="true"

                                >

                            </asp:DropDownList>

                              

                        </ContentTemplate>

                    </asp:UpdatePanel>

                </td>

            </tr>

            <tr>

                <td style="height: 130px;" valign="top">

                    Patient<br />

                    <asp:CheckBox ID="cbPatientAll" runat="server" Text="Check All" />

                </td>

                <td valign="top">

                    <asp:UpdatePanel ID="updatePanel2" runat="server">

                        <Triggers>

                            <asp:AsyncPostBackTrigger ControlID="ddlStudy" EventName="SelectedIndexChanged" />

                            <asp:AsyncPostBackTrigger ControlID="ddlSite" EventName="SelectedIndexChanged" />

                        </Triggers>

                        <ContentTemplate>

                            <telerik:RadComboBox ID="cblPatient" runat="server" Skin="Office2007" DataSourceID="PatientDS"

                                EmptyMessage="All Patients" DataTextField="TEXT" DataValueField="VALUE" ShowMoreResultsBox="true"

                                ItemsPerRequest="250" LoadingMessage="Retrieving Patients" EnableAutomaticLoadOnDemand="true"

                                Filter="Contains" MaxHeight="100px" Height="100px" AllowCustomText="false" OnItemDataBound="CB1_ItemDataBound"

                                HighlightTemplatedItems="False" Width="300px" OpenDropDownOnLoad="true" OnClientDropDownClosing="onDropDownClosing"

                                OnDataBound="CB1_DataBound">

                                <ItemTemplate>

                                    <div onclick="StopPropagation(event)">

                                        <asp:CheckBox runat="server" ID="chk1" />

                                        <asp:Label runat="server" ID="label1" AssociatedControlID="chk1"><%# DataBinder.Eval(Container, "Text") %></asp:Label>

                                    </div>

                                </ItemTemplate>

                                <CollapseAnimation Duration="200" Type="OutQuint" />

                                  

                            </telerik:RadComboBox>

                              

                            <asp:HiddenField ID="HV1" runat="server" />

                        </ContentTemplate>

                    </asp:UpdatePanel>

                </td>

            </tr>

        </table>

    </div>

    <script type="text/javascript" src="Scripts/jquery-1.4.1.min.js"></script>

    <script type="text/javascript">

        // NOTE - these two functions can be moved to the page

        function StopPropagation(e) {

            //cancel bubbling 

            e.cancelBubble = true;

            if (e.stopPropagation) {

                e.stopPropagation();

            }

        }

  

        function onDropDownClosing(sender, eventArgs) {

            eventArgs.set_cancel(true);

        }

        function allchecked(box) {

            var combo = $find(box);

            var items = combo.get_items();

            for (var i = 0; i < items.get_count(); i++) {

                var item = items.getItem(i);

                var chk1 = $get(combo.get_id() + '_i' + i + '_chk1');

                if (!chk1.checked) return false;

            }

            return true;

        }

        function onCheckBoxClick(me) {

            var cb = $("#<%=cbPatientAll.ClientID%>");

            cb.attr('checked', allchecked('<%=cblPatient.ClientID%>'));

  

            var chk1 = $get(me.id);

            var i = me.id.replace("<%=cblPatient.ClientID%>", "").replace("_chk1", "").replace("_i", "");

            //alert(i);

            var combo = $find('<%=cblPatient.ClientID%>');

            var items = combo.get_items();

            var item = items.getItem(i);

            var keepValue = $("#<%=HV1.ClientID %>").val();

            if (chk1.checked) {

                keepValue += item.get_value() + ',';

  

            }

            else {

                keepValue = keepValue.replace(item.get_value() + ',', '');

            }

            $("#<%=HV1.ClientID %>").val(keepValue);

        }

        $(document).ready(function () {

            $("#<%= cbPatientAll.ClientID %>").click(function (event) {

                var keepValue = "";

                var combo = $find('<%=cblPatient.ClientID%>');

                var items = combo.get_items();

                for (var i = 0; i < items.get_count(); i++) {

                    var item = items.getItem(i);

                    var chk1 = $get(combo.get_id() + '_i' + i + '_chk1');

                    chk1.checked = $('#' + this.id).is(':checked');

                    if ($('#' + this.id).is(':checked')) {

                        keepValue += item.get_value() + ',';

                    }

                }

                $("#<%=HV1.ClientID %>").val(keepValue);

  

            });

  

        });

        function pageLoad(sender, args) {

            $("#<%= ddlSite.ClientID %>").change(function () {

                //var combo = $find('<%=cblPatient.ClientID%>');

                //combo.clearItems();

                //combo.requestItems(' ', false);

  

            });

  

        }

          

  

  

    </script>

</asp:Content>

  

Default.aspx.cs

using System;

using System.Text;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using Telerik.Web.UI;

namespace RadCombo

{

    public partial class _Default : System.Web.UI.Page

    {

        private string Delimiter = ",";

        private DB myDBProc = new DB(); //DBProcessing Class Library

         

        protected void Page_Load(object sender, EventArgs e)

        {

  

            if (!this.IsPostBack)

            {

  

                myDBProc.GetStudy(ddlStudy);

            }

  

  

        }

        protected void CB1_ItemDataBound(object sender, RadComboBoxItemEventArgs e)

        {

            (e.Item.FindControl("chk1") as CheckBox).Attributes["onclick"] = "onCheckBoxClick(this)";

            if (HV1.Value.Contains(e.Item.Value)) (e.Item.FindControl("chk1") as CheckBox).Checked = true;

        }

        protected void CB1_DataBound(object sender, EventArgs e)

        {

            HV1.Value = "";

            StringBuilder sbValues = new StringBuilder();

            foreach (Telerik.Web.UI.RadComboBoxItem rcbItem in cblPatient.Items)

            {

                //If the box is checked return a value

                CheckBox cb = (CheckBox)rcbItem.FindControl("chk1");

                if (null != cb && cb.Checked)

                {

                    sbValues.Append(rcbItem.Value);

                    sbValues.Append(Delimiter);

                }

            }

  

            HV1.Value = sbValues.ToString();

  

        }

  

        protected void btnExecute_Click(object sender, EventArgs e)

        {

            string test = HV1.Value;

        }

        protected void ddlStudy_SelectedIndexChanged(object sender, EventArgs e)

        {

            myDBProc.GetSite(ddlSite, ddlStudy.SelectedValue);

        }

    }

}

  

DB.cs

sing System;

using System.Collections.Generic;

using System.Linq;

using System.Web;

using System.Data;

using System.Web.UI.WebControls;

namespace RadCombo

{

    public class DB

    {

        public void GetStudy( DropDownList list)

        {

  

            DataTable dt = new DataTable();

            dt.Columns.Add( new DataColumn("VALUE", typeof(int)));

            dt.Columns.Add(new DataColumn("TEXT", typeof(string)));

            DataRow dr = dt.NewRow();

            dr["Value"] = 1;

            dr["TEXT"] = "One";

            dt.Rows.Add(dr);

            list.DataValueField = dt.Columns["VALUE"].ColumnName;

            list.DataTextField = dt.Columns["TEXT"].ColumnName;

            list.DataSource = dt;

            list.DataBind();

            list.Items.Insert(0, new ListItem("Select a Study", ""));

        }

        public void GetSite( DropDownList list, string Study)

        {

              

            if (string.IsNullOrEmpty(Study) || Study == "%")

            {

                list.Items.Clear();

                return;

            }

  

            DataTable dt = new DataTable();

            dt.Columns.Add(new DataColumn("VALUE", typeof(int)));

            dt.Columns.Add(new DataColumn("TEXT", typeof(string)));

            DataRow dr = dt.NewRow();

            dr["Value"] = 11;

            dr["TEXT"] = "Eleven";

            dt.Rows.Add(dr);

            list.DataValueField = dt.Columns["VALUE"].ColumnName;

            list.DataTextField = dt.Columns["TEXT"].ColumnName;

            list.DataSource = dt;

            list.DataBind();

            list.Items.Insert(0, new ListItem("All Sites", "%"));

            list.Items.Insert(0, new ListItem("Select a Site", ""));

        }

        public DataTable GetPatient(string Study, string Site)

        {

  

            if (string.IsNullOrEmpty(Study) || Study == "%" || string.IsNullOrEmpty(Site))

            {

  

                 

                return new DataTable();

            }

            DataTable dt = new DataTable();

            dt.Columns.Add(new DataColumn("VALUE", typeof(int)));

            dt.Columns.Add(new DataColumn("TEXT", typeof(string)));

            DataRow dr = dt.NewRow();

            dr["Value"] = 100;

            dr["TEXT"] = "One Hundred";

            dt.Rows.Add(dr);

            dr = dt.NewRow();

            dr["Value"] = 101;

            dr["TEXT"] = "One Hundred And One";

            dt.Rows.Add(dr);

            dr = dt.NewRow();

            dr["Value"] = 102;

            dr["TEXT"] = "One Hundred And Two";

            dt.Rows.Add(dr);

  

             

            return dt;

        }

    }

      

  

}

[Dimitar Terziev]

Hello Quynh,

I've already answered to your support ticket regarding this issue, so lets continue the discussion there.

Best wishes,
Dimitar Terziev
the Telerik team

[Quynh]

hi, to whom interested in this post. the solution they gave me is on the telerik comnobox add OnClientLoad="OnClientLoad"
and on client javascript add

function OnClientLoad(sender) {

 

    setTimeout(function () { sender.requestItems(""); }, 0);

   }

It will try to requestItems on every load, but it seems the way for now

Regards,
Quynh