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error with xmlhttppanel and combobox with checkboxes

3 Answers 80 Views

XmlHttpPanel

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

moegal asked on 05 Nov 2012, 11:21 AM

I have a page with a combo(ComboBox1) in a xmlhttppanel(XmlPanel1) and also a stand alone checkbox combo(RadComboBox1). After I call XmlPanel1 and select an item from ComboBox1, then select a checkbox item from the RadComboBox1 I get an error.

I have created a very simple example to show the error. Am I doing something wrong?

Uncaught TypeError: Cannot call method 'get_checked' of null

Telerik.Web.UI.WebResource.axd: 3642

c.RadComboBox.prototype._onCheckBoxCheck=function(f){var d=f.target.nodeName;

if(d=="LABEL"){f.preventDefault();

}var h=this._findNearestItem(f.target);

var j=h!=null?h:this._extractItemFromDomElement(f.target);

if(this.raise_onItemChecking(j,f)){f.preventDefault();

return;

}j.set_checked(!j.get_checked());
Uncaught TypeError: Cannot call method 'get_checked' of null

this.raise_onItemChecked(j,f);

this._updateComboBoxText();

if(this._checkAllItemsElement!=null){this._updateCheckAllState();

}if(this._postBackOnCheck){var g={Command:"Check",Index:j.get_index()};

this.postback(g);

}};

<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Main.aspx.cs" Inherits="Main" %>

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

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">

<head id="Head1" runat="server">

<title></title>

</head>

<body>

<form id="form1" runat="server">

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

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

<script type="text/javascript">

function SetValue() {

var panel = $find("<%=XmlPanel1.ClientID %>");

panel.set_value("test");

}

</script>

</telerik:RadScriptBlock>

<div>

<telerik:RadComboBox ID="RadComboBox1" runat="server" CheckBoxes="true" EnableCheckAllItemsCheckBox="true"

Width="300" Label="Select book genres:">

<Items>

<telerik:RadComboBoxItem Text="Arts" />

<telerik:RadComboBoxItem Text="Biographies" />

<telerik:RadComboBoxItem Text="Children's Books" />

<telerik:RadComboBoxItem Text="Computers & Internet" />

<telerik:RadComboBoxItem Text="Cooking" />

<telerik:RadComboBoxItem Text="History" />

<telerik:RadComboBoxItem Text="Fiction" />

<telerik:RadComboBoxItem Text="Mystery" />

<telerik:RadComboBoxItem Text="Nonfiction" />

<telerik:RadComboBoxItem Text="Romance" />

<telerik:RadComboBoxItem Text="Science Fiction" />

<telerik:RadComboBoxItem Text="Travel" />

</Items>

</telerik:RadComboBox>

</div>

<div>

<input value="Set Value" onclick="SetValue(); return false;" type="button" />

<div>

<telerik:RadXmlHttpPanel ID="XmlPanel1" runat="server" OnServiceRequest="XmlPanel1_ServiceRequest"

EnableClientScriptEvaluation="true">

<telerik:RadComboBox ID="ComboBox1" runat="server">

</telerik:RadComboBox>

</telerik:RadXmlHttpPanel>

</div>

</form>

</body>

</html>

using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Web;

using System.Web.UI;

using System.Web.UI.WebControls;

using Telerik.Web.UI;

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

{

protected void Page_Load(object sender, EventArgs e)

{

}

protected void XmlPanel1_ServiceRequest(object sender, Telerik.Web.UI.RadXmlHttpPanelEventArgs e)

{

ArrayList itemsList = new ArrayList();

itemsList.Add("Beverages");

itemsList.Add("Condiments");

itemsList.Add("Confections");

ComboBox1.DataSource = itemsList;

ComboBox1.DataBind();

}

the error is stopping my other javascript code from working.

Help!! Marty

3 Answers, 1 is accepted

Accepted

answered on 09 Nov 2012, 11:30 AM

Hi Marty,

I am glad this helped you resolve the problem!

As explained in the linked help article, the page does not go through the normal life cycle when RadXmlHttpPanel is used. This requires evaluation of the scripts and stylesheets that are loaded by the controls in the panel, which is not possible if RadScriptManager or RadStyleSheetManager is used on the page, i.e. the scripts (and the stylesheets) are combined into a single file.

Regards,
Slav
the Telerik team

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