adding control to groupheader

[debbie f]

I have seen several posts on this topic, but have not seen a solution that will work yet.  I want to add a linkbutton to my group header that will use data from the group header in the postback.

I have something like the following:

LinkButton lnk = new LinkButton();
lnk.ID = "lnkReservations";
lnk.Text = "View All";
lnk.CommandArgument = (DataRowView)item.DataItem["employer_id"].ToString();
lnk.Command += new CommandEventHandler(lnkReservations_Command);
item.DataCell.Controls.Add(lnk);

I have tried adding to the event handlers for PreRender, ItemCreated, ItemDataBound but have not been successful in any of those attempts in getting the linkbutton to behave correctly.

Is there a simple solution to add a linkbutton to a groupheader that will execute a function based on the data/header where the control sits?  Is there any kind of special column that I can add to turn a header into a linkbutton?

[Shinu]

Hi Debbie,

Try adding the linkbutton in both ItemDataBound event and ItemCreated Event as shown below.

CS:

  protected void RadGrid1_ItemCreated(object sender, GridItemEventArgs e)
    {
        if (e.Item is GridGroupHeaderItem)
        {
            GridGroupHeaderItem item = e.Item as GridGroupHeaderItem;
            LinkButton lnk = new LinkButton();
            lnk.ID = "lnkReservations";
            lnk.Text = "View All";
            lnk.Command += new CommandEventHandler(lnkReservations_Command);
            item.DataCell.Controls.Add(lnk);

        }


    }

    protected void RadGrid1_ItemDataBound(object sender, Telerik.Web.UI.GridItemEventArgs e)
    {
        if (e.Item is GridGroupHeaderItem)
        {
            GridGroupHeaderItem item = e.Item as GridGroupHeaderItem;
            LinkButton lnk = new LinkButton();
            lnk.ID = "lnkReservations";
            lnk.Text = "View All";
            item.DataCell.Controls.Add(lnk);
        }


    }

    void lnkReservations_Command(object sender, CommandEventArgs e)
    {
        LinkButton lnkReservations = (LinkButton)sender;
        GridGroupHeaderItem groupHeader = (GridGroupHeaderItem)lnkReservations.NamingContainer;
    }

Thanks
Shinu.

[debbie f]

I initially tried that sample from another forum post.  However, when the linkbutton's command is fired, groupHeader.DataItem is null. Is there anyway to actually access the data that I need to process the logic necessary for my linkbutton?  Even if there is a way to access the itemindex and pull from the datakeys, that would help.

[Shinu]

Hi Debbie,

I hope you are trying to access the GroupByField from the GridGridGroupHeaderItem on clicking the linkbutton. If so try the following code snippet.

CS:

  void lnkReservations_Command(object sender, CommandEventArgs e)
    {
        LinkButton lnkReservations = (LinkButton)sender;
        GridGroupHeaderItem groupHeader = (GridGroupHeaderItem)lnkReservations.NamingContainer;
        string strtxt = groupHeader.DataCell.Text;
        string[] arr = strtxt.Split(':');
        string strGroupByField = arr[0].ToString();
    }

Thanks
Shinu.

[Princy]

Hi,

A suggestion would be to split the  DataCell text of the group header and then loop through the GridDataItems to find the item with the particular data.

 LinkButton lnkReservations = (LinkButton)sender;
            GridGroupHeaderItem groupHeader = (GridGroupHeaderItem)lnkReservations.NamingContainer;
            string strText = groupHeader.DataCell.Text;
            string[] arr = strText.Split(':');
            foreach (GridDataItem  item in  RadGrid1.Items)
            {
                if (arr[1].TrimStart() == item[arr[0].ToString()].Text)
                {
                    //get the data
                }

            }

Thanks,
Princy

[Zyguy]

Hi,

I found this example while searching for a way to achieve my goal:

I have a Radgrid grouped by Order ID's, with several items possible in each order group. I would like to make a button link in the header of each Order ID group, which will export an Invoice for the contents of the Order group.

I tried to translate this example into VB however get the error: "Expression of type 'Telerik.Web.UI.GridItem' can never be of type 'Telerik.WebControls.GridGroupHeaderItem'."

Can you please advise how I could adapt this example to achieve my goal or perhaps use another method such as the native Radgrid Export methods in order to export an HTML or PDF invoice for each Order ID group.     

[Shinu]

Hi Zyguy,

I hope you are trying to export the Grouped data on clicking the Export button in the corresponding GridGroupHeader. Give a try with the following code snippet and see if it helps.

VB:

     Protected Sub RadGrid1_ItemCreated(ByVal sender As Object, ByVal e As GridItemEventArgs)
         If TypeOf e.Item Is GridGroupHeaderItem Then
             Dim item As GridGroupHeaderItem = TryCast(e.Item, GridGroupHeaderItem)
             Dim lnk As New LinkButton()
             lnk.ID = "lnkReservations"
             lnk.Text = "ExportGroup"
             AddHandler lnk.Command, AddressOf lnkReservations_Command
             item.DataCell.Controls.Add(lnk)

         End If

     End Sub

     Protected Sub RadGrid1_ItemDataBound(ByVal sender As Object, ByVal e As GridItemEventArgs)


         If TypeOf e.Item Is GridGroupHeaderItem Then
             Dim item As GridGroupHeaderItem = TryCast(e.Item, GridGroupHeaderItem)
             Dim lnk As New LinkButton()
             lnk.ID = "lnkReservations"
             lnk.Text = "ExportGroup"
             item.DataCell.Controls.Add(lnk)
         End If


     End Sub
     Private Sub lnkReservations_Command(ByVal sender As Object, ByVal e As CommandEventArgs)
         Dim lnkReservations As LinkButton = DirectCast(sender, LinkButton)
         Dim currentHeaderitm As GridGroupHeaderItem = DirectCast(lnkReservations.NamingContainer, GridGroupHeaderItem)
         For Each headerItem As GridGroupHeaderItem In RadGrid1.MasterTableView.GetItems(GridItemType.GroupHeader)
             If headerItem.GroupIndex <> currentHeaderitm.GroupIndex Then
                 Dim children As GridItem() = headerItem.GetChildItems()
                 For Each child As GridItem In children
                     Dim dataItem As GridDataItem = TryCast(child, GridDataItem)
                     dataItem.Visible = False
                 Next
                 headerItem.Visible = False
             End If
         Next
         RadGrid1.ExportSettings.OpenInNewWindow = True
         RadGrid1.ExportSettings.ExportOnlyData = True
         RadGrid1.MasterTableView.ExportToPdf()
     End Sub

Hope this helps..
Shinu

[Christopher Taylor]

I'm using just text to adjust the group header.  I want to use a subobject (i.e Component.ComponentProperty ) but can't get this to work.

So in turn.  I'm attaching to the ItemCreated and ItemDataBound events as mentioned in this article.  However, I've noticed some undesireable behavior I'm not sure how to correct. 

When it first renders, the group header has the text I would like.  But any subsequent expand and collapse still uses the data in the <SelectGroup> section. 

What's the best way to do this?

Thanks,
Chris

-edit: Added code

public partial class ComponentList : System.Web.UI.Page
    {

        SiteManagerDataDataContext dataContext;
        protected void Page_Load(object sender, EventArgs e)
        {

            ComponentsDataSource.ContextCreated += new EventHandler<LinqDataSourceStatusEventArgs>(ComponentsDataSource_ContextCreated);
            RadGrid1.ItemCreated += new Telerik.Web.UI.GridItemEventHandler(RadGrid1_ItemCreated);
            RadGrid1.ItemDataBound += new GridItemEventHandler(RadGrid1_ItemDataBound);


        }


        void RadGrid1_ItemDataBound(object sender, GridItemEventArgs e)
        {
            if (e.Item is Telerik.Web.UI.GridGroupHeaderItem)
            {
                DataRowView drv = e.Item.DataItem as DataRowView;
                int componentId = int.Parse(drv["ComponentId"].ToString());
                var row = dataContext.Components.FirstOrDefault(o => o.ComponentId == componentId);


                GridGroupHeaderItem item = e.Item as GridGroupHeaderItem;
                LiteralControl litText = new LiteralControl(row.ComponentName);

                item.DataCell.Controls.Clear();
                item.DataCell.Controls.Add(litText);

            }
        }



        void RadGrid1_ItemCreated(object sender, Telerik.Web.UI.GridItemEventArgs e)
        {
            if (e.Item is Telerik.Web.UI.GridGroupHeaderItem)
            {
                DataRowView drv = e.Item.DataItem as DataRowView;
                int componentId = int.Parse(drv["ComponentId"].ToString());
                var row = dataContext.Components.FirstOrDefault(o => o.ComponentId == componentId);


                GridGroupHeaderItem item = e.Item as GridGroupHeaderItem;
                LiteralControl litText = new LiteralControl(row.ComponentName);

                item.DataCell.Controls.Clear();
                item.DataCell.Controls.Add(litText);

            }
        }



        void ComponentsDataSource_ContextCreated(object sender, LinqDataSourceStatusEventArgs e)
        {
            dataContext = e.Result as SiteManagerDataDataContext;
        }

aspx code

<%@ Page Title="" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true"
    CodeBehind="ComponentList.aspx.cs" Inherits="DNNSiteManager.Components.ComponentList" %>

<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server">
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server">
    <asp:ScriptManager runat="server"></asp:ScriptManager>
    <telerik:RadGrid ID="RadGrid1" runat="server" AutoGenerateColumns="False" DataSourceID="ComponentsDataSource"
        GridLines="None">
        <MasterTableView DataKeyNames="ComponentVersionId" DataSourceID="ComponentsDataSource">
            <RowIndicatorColumn>
                <HeaderStyle Width="20px"></HeaderStyle>
            </RowIndicatorColumn>
            <GroupByExpressions>
               <telerik:GridGroupByExpression >
                    <SelectFields>
                        <telerik:GridGroupByField FieldAlias="ComponentId" FieldName="ComponentId" FormatString="" HeaderValueSeparator="-" />
                    </SelectFields>
                    <GroupByFields>
                        <telerik:GridGroupByField FieldAlias="ComponentId" FieldName="ComponentId" SortOrder="Descending"></telerik:GridGroupByField>
                    </GroupByFields>
                </telerik:GridGroupByExpression>
            </GroupByExpressions>
            <ExpandCollapseColumn>
                <HeaderStyle Width="20px"></HeaderStyle>
            </ExpandCollapseColumn>
            <Columns>
        <telerik:GridBoundColumn DataField="ComponentVersionId" DataType="System.Int32" HeaderText="ComponentVersionId"
                    ReadOnly="True" SortExpression="ComponentVersionId" UniqueName="ComponentVersionId">
                </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="Version" HeaderText="Version" SortExpression="Version"
                    UniqueName="Version">
                </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="PackageUri" HeaderText="PackageUri" SortExpression="PackageUri"
                    UniqueName="PackageUri">
                </telerik:GridBoundColumn>
        <telerik:GridBoundColumn DataField="ComponentId" DataType="System.Int32" HeaderText="ComponentId"
                    SortExpression="ComponentId" UniqueName="ComponentId">
                </telerik:GridBoundColumn>
            </Columns>
        </MasterTableView>
    </telerik:RadGrid>
    <asp:LinqDataSource runat="server" ID="ComponentsDataSource" ContextTypeName="DNNSiteManager.Data.SiteManagerDataDataContext"
        EntityTypeName="" TableName="ComponentVersions">
    </asp:LinqDataSource>
</asp:Content>

[Iana Tsolova]

Hi Christopher,

Could you please try modifying your code as below and see if this works for you:

protected void Page_Load(object sender, EventArgs e)
{
    ComponentsDataSource.ContextCreated += new EventHandler<LinqDataSourceStatusEventArgs>(ComponentsDataSource_ContextCreated);
    RadGrid1.ItemDataBound += new GridItemEventHandler(RadGrid1_ItemDataBound);
}
void RadGrid1_ItemDataBound(object sender, GridItemEventArgs e)
{
    if (e.Item is Telerik.Web.UI.GridGroupHeaderItem)
    {
         DataRowView drv = e.Item.DataItem as DataRowView;
         int componentId = int.Parse(drv["ComponentId"].ToString());
         var row = dataContext.Components.FirstOrDefault(o => o.ComponentId == componentId);
         GridGroupHeaderItem item = e.Item as GridGroupHeaderItem;
         item.DataCell.Text = row.ComponentName;
    }
}

Regards,
Iana
the Telerik team

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[Kavya]

Hi princy
Please help me with this module

I know this is very old Thread. But i am trying to use your'e code . I also have

grid_PreRender function. Eventhough i add linkbutton in Itemcreated and Itemdatabound the link button is cleared in Prerender function.
I want to see my GroupName appended with the count of items in group header(reason to use Prerender).

Below is the way i am doing it

Protected Sub RadGrid1_ItemCreated(ByVal sender As Object, ByVal e As GridItemEventArgs)  

        If TypeOf e.Item Is GridGroupHeaderItem Then  

            Dim item As GridGroupHeaderItem = TryCast(e.Item, GridGroupHeaderItem)  

            Dim lnk As New LinkButton()  

            lnk.ID = "lnkReservations"  

            lnk.Text = "ExportGroup"  

            AddHandler lnk.Command, AddressOf lnkReservations_Command  

            item.DataCell.Controls.Add(lnk)  

               

        End If  

           

    End Sub  

       

    Protected Sub RadGrid1_ItemDataBound(ByVal sender As Object, ByVal e As GridItemEventArgs)  

           

           

        If TypeOf e.Item Is GridGroupHeaderItem Then  

            Dim item As GridGroupHeaderItem = TryCast(e.Item, GridGroupHeaderItem)  

            Dim lnk As New LinkButton()  

            lnk.ID = "lnkReservations"  

            lnk.Text = "ExportGroup"  

            item.DataCell.Controls.Add(lnk)  

        End If  

           

           

    End Sub  

    Private Sub lnkReservations_Command(ByVal sender As Object, ByVal e As CommandEventArgs)  

        Dim lnkReservations As LinkButton = DirectCast(sender, LinkButton)  

        Dim currentHeaderitm As GridGroupHeaderItem = DirectCast(lnkReservations.NamingContainer, GridGroupHeaderItem)  

        For Each headerItem As GridGroupHeaderItem In RadGrid1.MasterTableView.GetItems(GridItemType.GroupHeader)  

            If headerItem.GroupIndex <> currentHeaderitm.GroupIndex Then  

                Dim children As GridItem() = headerItem.GetChildItems()  

                For Each child As GridItem In children  

                    Dim dataItem As GridDataItem = TryCast(child, GridDataItem)  

                    dataItem.Visible = False  

                Next  

                headerItem.Visible = False  

            End If  

        Next  

        RadGrid1.ExportSettings.OpenInNewWindow = True  

        RadGrid1.ExportSettings.ExportOnlyData = True  

        RadGrid1.MasterTableView.ExportToPdf()  

    End Sub  

Private Sub RadGrid1_PreRender(ByVal sender As Object, ByVal e As System.EventArgs) Handles RadGrid1.PreRender
'Get items count in each group
 Dim total2 As Integer = 0

For Each item As GridGroupHeaderItem In RadGrid1.MasterTableView.GetItems(GridItemType.GroupHeader)

Dim dataItem As GridDataItem = Nothing
For Each Gitem As GridItem In item.GetChildItems()
If TypeOf Gitem Is GridDataItem Then
dataItem = TryCast (Gitem, GridDataItem)
If Not dataItem Is Nothing Then
total2 += 1
End
Next
item.DataCell.Text = " Records " & total2 & " " & item.DataCell.Text

total2 = 0
Next


End Sub

 

If i take out Prerender and try eventhough lnkreservation finction is called it is not exported to pdf or excel

Please suggest what changes i need to do

 

Thanks
Kavya 

 

[Iana Tsolova]

Hello Kavya,

I checked your code and I can see that in the PreRender event handler you are overriding the content of the GridGroupHeaderItem. Therefore it is expected the LinkButton event to fire only in case you comment the PreRender code. However, a possible reason for the grid not to be exported is if it is ajaxified and you are not disabling ajax upon export. Can you confirm this is not the case?

Additionally, find more information on how to export from ajaxified grid in the below article:
http://www.telerik.com/help/aspnet-ajax/grdexportwithajax.html

All the best,
Iana
the Telerik team

[Kavya]

Hello Iana

I still need Prerender for the count .Please can you suggest me how not to override the GridGroupHeaderItem but still append the count.

This is the way i ma trying to print each group

Dim

 

lnkReservations As LinkButton = DirectCast(sender, LinkButton)

 

 

 

Dim currentHeaderitm As GridGroupHeaderItem = DirectCast(lnkReservations.NamingContainer, GridGroupHeaderItem)

 

 

 

For Each headerItem As GridGroupHeaderItem In grid.MasterTableView.GetItems(GridItemType.GroupHeader)

 

 

 

If headerItem.GroupIndex <> currentHeaderitm.GroupIndex Then

 

 

Dim children As GridItem() = headerItem.GetChildItems()

 

 

 

For Each child As GridItem In children

 

 

 

Dim dataItem As GridDataItem = TryCast(child, GridDataItem)

 

 

dataItem.Visible =

False

 

 

Next

 

headerItem.Visible =

False

 

 

End If

 

 

Next

 

grid.ExportSettings.OpenInNewWindow =

True

 

grid.ExportSettings.ExportOnlyData =

True

 

grid.ExportSettings.Pdf.AllowPrinting =

True

 

grid.MasterTableView.ExportToExcel()

How to disable Ajax here in this code

Please suggest and Thank you for the quick response and great support

Thanks
Kavya

[Kavya]

Hi Iana

As per your information i disabled Ajax and also added the count at cell(1) as print is added on Cell(0) on GroupHeaderItem. Its working great

The only other problem i have is the print is not working when i load grid fro first time.
For Ex if i have 3 groups and i click on print for 1st group it show as if its loading and the hides all other groups. But export doesn't come up then again when i click on print it prints.This is happening only when the RadGrid is loaded for the first time.

Please any suggestions

Thanks
Kavya

[Iana Tsolova]

Hi Kavya ,

Can you try debugging the page and see if on first click of the export button, the server code for exporting the grid is executed at all? A possible reason for it not to be hit is javascript error. Check that out as well.

Greetings,
Iana
the Telerik team

[Kavya]

Hi Iana

I tried to debug each step when print is called for the frist time for my surprise it actually goes to

lnkReservations_Command

function tries to hide all other groups but the export is not working.

I don't get any javascript error also.Please can you suggest what else i need to change
Below is the Group

Private Sub lnkReservations_Command(ByVal sender As Object, ByVal e As CommandEventArgs)
        Try
            Dim lnkReservations As LinkButton = DirectCast(sender, LinkButton)
            Dim currentHeaderitm As GridGroupHeaderItem = DirectCast(lnkReservations.NamingContainer, GridGroupHeaderItem)
            For Each headerItem As GridGroupHeaderItem In grid.MasterTableView.GetItems(GridItemType.GroupHeader)
                If headerItem.GroupIndex <> currentHeaderitm.GroupIndex Then
                    Dim children As GridItem() = headerItem.GetChildItems()
                    For Each child As GridItem In children
                        Dim dataItem As GridDataItem = TryCast(child, GridDataItem)
                        dataItem.Visible = False
                    Next
                    headerItem.Visible = False
                End If
            Next
           grid.ExportSettings.OpenInNewWindow = True
            grid.EnableAJAX = False
            grid.ExportSettings.ExportOnlyData = True
           grid.ExportSettings.Pdf.AllowPrinting = True
            grid.MasterTableView.ExportToExcel()

        Catch ex As Exception
            Throw New Exception("Print_btn_Click" & ex.Message)

        End Try

    End Sub

Print function code

[Iana Tsolova]

Hi Kavya,

Please confirm you have followed the steps for disabling ajax described here. If the issue persists, I would ask you to send me a runnable page so I can debug it locally and thus try finding what went wrong.

Kind regards,
Iana
the Telerik team

[Kavya]

Iana

I tried the link you sent me but not luck
As my grid is not residing in Updatepanel i just tried using

<

 

script type="text/javascript">

 

 

function onRequestStart(sender, args)

 

 

{

 

 

if (args.get_eventTarget().indexOf("chk_print") >= 0)

 

 

args.set_enableAjax(

false);

 

 

}

</

 

script>

 

Please let me know what else ican change
Do you want me to send client & server side code if that will help


Thanks
Kavya

[Iana Tsolova]

Hi Kavya,

Indeed, can you specify how you ajaxified the grid in your case? You can share the code for that if applicable.

All the best,
Iana
the Telerik team

[Kavya]

Iana

Actually i removed

EnableAJAX

 

="True" EnableAJAXLoadingTemplate="True"

 

And it is working perfectly. I didn't need Ajax for anything so now its working .

Iana thank you for the great support

Kavya