Pagination not working in RadGrid control

[krishna]

Hi,

      I am using a RadGrid control (Rad Controls for ASP.NET AJAX Q3 2009 NET20) to display data. I am not sure why my  control is not displaying data at all when I navigate from my first page. Below is the sample I am working with. Please help me understand what I am missing and how to rectify.

Thanks in advance.

Regards,
Krishna Chaduvula.

WEB.CONFIG (HTTP Handler)
<add path="Telerik.Web.UI.WebResource.axd" verb="*" type="Telerik.Web.UI.WebResource, Telerik.Web.UI" validate="false" />

ASPX Page:

<%

@ Page Language="VB" AutoEventWireup="false" CodeFile="testRadGrid.aspx.vb" Inherits="testRadGrid" %>

 

 

<%

@ 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 runat="server">

 

 

<title></title>

 

 

</

 

head>

 

 

<

 

body>

 

 

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

 

 

<div>

 

 

 

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

 

 

</asp:ScriptManager>

 

 

 

<telerik:RadAjaxManager ID="RadAjaxManager1" runat="server">

 

 

<AjaxSettings>

 

 

<telerik:AjaxSetting AjaxControlID="grdPayStatements">

 

 

<UpdatedControls>

 

 

<telerik:AjaxUpdatedControl ControlID="grdPayStatements" />

 

 

</UpdatedControls>

 

 

</telerik:AjaxSetting>

 

 

 

</AjaxSettings>

 

 

</telerik:RadAjaxManager>

 

 

<telerik:RadGrid runat="server" ID="grdPayStatements" AllowPaging="True"

 

 

 

AutoGenerateColumns="False" GridLines="None" GroupingEnabled="False"

 

 

 

HorizontalAlign="Center" >

 

 

<MasterTableView>

 

 

<RowIndicatorColumn>

 

 

<HeaderStyle Width="20px"></HeaderStyle>

 

 

</RowIndicatorColumn>

 

 

<ExpandCollapseColumn>

 

 

<HeaderStyle Width="20px"></HeaderStyle>

 

 

</ExpandCollapseColumn>

 

 

<Columns>

 

 

<telerik:GridHyperLinkColumn AllowFiltering="False"

 

 

 

DataNavigateUrlFields="SEQNR" DataNavigateUrlFormatString="test.aspx?id={0}"

 

 

 

DataTextField="PayDate" HeaderText="Pay Date" UniqueName="column1">

 

 

</telerik:GridHyperLinkColumn>

 

 

<telerik:GridBoundColumn AllowFiltering="False" AllowSorting="False"

 

 

 

DataField="TotalGross" DefaultInsertValue="" HeaderText="Total Gross"

 

 

 

UniqueName="column2">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn AllowFiltering="False" AllowSorting="False"

 

 

 

DataField="NetPay" DefaultInsertValue="" HeaderText="Net Pay"

 

 

 

UniqueName="column3">

 

 

</telerik:GridBoundColumn>

 

 

<telerik:GridBoundColumn AllowFiltering="False" AllowSorting="False"

 

 

 

DataField="SEQNR" DefaultInsertValue="" HeaderText="SEQNR" UniqueName="column"

 

 

 

Visible="False">

 

 

</telerik:GridBoundColumn>

 

 

</Columns>

 

 

</MasterTableView>

 

 

</telerik:RadGrid>

 

 

</div>

 

 

</form>

 

 

</

 

body>

 

 

</

 

html>


CODE BEHIND

 

 

 

Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

 

 

 

 

If Not Page.IsPostBack Then

 

 

 

 

 

 

 

LoadData()

 

 

 

End If

 

 

 

 

 

 

 

 

 

End Sub

 

 

 

 

 

 

 

 

 

Private Sub LoadData()

 

 

 

 

Dim dt As DataTable = New DataTable()

 

 

dt.Columns.Add(

 

"SEQNR")

 

 

dt.Columns.Add(

 

"PayDate")

 

 

dt.Columns.Add(

 

"TotalGross")

 

 

dt.Columns.Add(

 

"NetPay")

 

 

 

 

Dim t As Double = 0

 

 

 

 

For i As Integer = 0 To 29

 

 

 

 

Dim dr As DataRow = dt.NewRow()

 

 

dr(

 

"PayDate") = DateTime.Today().AddDays(i)

 

 

dr(

 

"NetPay") = 2000

 

 

t += 2000

 

dr(

 

"TotalGross") = t

 

 

dr(

 

"SEQNR") = i + 1

 

 

dt.Rows.Add(dr)

 

 

 

Next

 

 

 

 

 

 

 

grdPayStatements.DataSource = dt

 

grdPayStatements.DataBind()

 

 

 

End Sub

 

 

[Pavlina]

Hi Krishna,

Note that simple data-binding through the DataBind() method can be used in simple scenarios which does not require complex operations like paging insert/delete/update, grouping, hierarchy relations, etc. Also keep in mind that if you choose simple data-binding, you will need to assign data-source and rebind the grid after each operation same like MS DataGrid.

If you are using advanced features for grid, a better option will be using AdvancedDataBinding technique as shown in the demo below.
Advanced Data Binding

Best wishes,
Pavlina
the Telerik team

[krishna]

Pavlina,

  Thanx for the quick response. The link you specified in your post looks like it is broken. So did you meant to say that I have to use advanced Data bindings to incorporate paging?

Thank you.

Regards,
Krishna Chaduvula

[krishna]

Issue with the RadGrid control for Paging is that when the Page index changed, there was a post back event and the datasource that I set earlier was no longer available, So my Solution to this is to add the Datasource to the session and in the "Page_IndexChanged" event, get the datasource from the session and rebind it to the control. Below is the code I had to add:

 

 

Protected

 

 

 

Sub grdPayStatements_PageIndexChanged(ByVal source As Object, ByVal e As Telerik.Web.UI.GridPageChangedEventArgs) Handles

grdPayStatements.PageIndexChanged

  

 

 

Dim dtPayHistory As New

DataTable

 

 

 

 

 

If Not Session("dtPayHistory") Is Nothing

Then

 

 

dtPayHistory = CType(Session("dtPayHistory"

), DataTable)

RadGrid1.Dispose() 

RadGrid1.DataSource = dtPayHistory

 

RadGrid1.DataBind() 

RadGrid1.CurrentPageIndex = e.NewPageIndex

 End If

 

 

End

Sub

 

 

[Pavlina]

Hi Krishna,

Please excuse me for the broken link. Here is the correct one:
http://demos.telerik.com/aspnet-ajax/grid/examples/programming/needdatasource/defaultcs.aspx

Regards,
Pavlina
the Telerik team