GridView.Footer - LinkButton problem

I have an application where I need to assign a link button to the footer. For some reason, when I click on the link button (in the footer) nothing happens. I've been working on this for days and need good help please:

Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs) Handles GridView1.RowDataBound 
Dim tabledata As Data.DataRowView = e.Row.DataItem

If e.Row.RowType = DataControlRowType.Footer Then

myLinkButton.Text = "Select"

myLinkButton.CommandName = "SelectFooter"

AddHandler myLinkButton.Click, New EventHandler(AddressOf ClickHandler) 
e.Row.Cells(0).Controls.Add(myLinkButton)

e.Row.Cells(2).Text = "Selection Total"

e.Row.Cells(3).Text = Session("TotalHours") 
End If

End Sub

Code (markup):

Public Sub ClickHandler(ByVal sender As Object, ByVal e As EventArgs) 

'Handle LinkButton click event here. But this event never gets called...

End Sub

Code (markup):

Protected Sub GridView1_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)

        If e.CommandName = "Select" Then
            Dim index As Integer = Convert.ToInt32(e.CommandArgument)
            Dim mySelectedRow As GridViewRow = GridView1.Rows(index)
            Dim mySelectedCell As TableCell

            mySelectedCell = mySelectedRow.Cells(1)
            Equipment_ID = mySelectedCell.Text.ToString

            GetItemDetail(Equipment_ID)
            DisplayItemDetail()
        End If

        If e.CommandName = "SelectFooter" Then
            ClickHandler(sender, e)
        End If

    End Sub

Code (markup):

 

I don't see you declare the button:
Dim myLinkButton As New LinkButton

I can only assume that you declare it globally. Try declaring it within the GridView1_RowDataBound() sub. I don't know whether this will make a difference but otherwise i can't see any other problem.

-EDIT-
actually i don't think it's gonna make a difference.

 

This works for me:

    Public Sub ClickHandler(ByVal sender As Object, ByVal e As EventArgs)
        MsgBox("test")
    End Sub

    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
        Dim myLinkButton As New LinkButton
        myLinkButton.Text = "Select"
        AddHandler myLinkButton.Click, New EventHandler(AddressOf ClickHandler)
        GridView1.FooterRow.Cells(0).Controls.Add(myLinkButton)
    End Sub

Code (markup):

 

Hi camjohnson95,

I very much appreciate you helping me out. I've been working on this problem for days without getting anywhere. This is now what I have in the RowDataBound (added the dim for LinkButton). When I run the app the footer shows up and there is a "Select" that I can click in cell(0). When I click it, nothing happens (does not enter the ClickHandler event) and the "Select" text disappears (the cell goes blank). Do I need to do something in the mark up section (I would not think so but I am not very familiar with .Net development). Instead of using a handler could I use a selectcommand? Just a thought. Again, I am very grateful for any help....

Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs) Handles GridView1.RowDataBound

        Dim tabledata As Data.DataRowView = e.Row.DataItem
        Dim myLinkButton As New LinkButton

        If e.Row.RowType = DataControlRowType.Footer Then
            myLinkButton.Text = "Select"
            AddHandler myLinkButton.Click, New EventHandler(AddressOf ClickHandler)
            myLinkButton.CommandName = "SelectFooter"
            e.Row.Cells(0).Controls.Add(myLinkButton)
            e.Row.Cells(2).Text = "Selection Total"
            e.Row.Cells(3).Text = Session("TotalHours")
        End If

    End Sub

Code (markup):

Public Sub ClickHandler(ByVal sender As Object, ByVal e As EventArgs)

        Dim mystr As String
        mystr = "Hello"
        'Handle LinkButton click event here. But this event never gets called...

 End Sub

Code (markup):

I have included the mark up code just in case.

<asp:GridView ID="GridView1" runat="server" Style="z-index: 102; left: 0px; position: relative;
                        top: 43px; border-right: gray thin solid; border-top: gray thin solid; border-left: gray thin solid;
                        border-bottom: gray thin solid; font-size: 12px; overflow: hidden; clip: rect(auto auto auto auto);"
                        Width="342px" AllowPaging="True" AllowSorting="True" Font-Size="Small" AutoGenerateColumns="False"
                        CellSpacing="2" HorizontalAlign="Left" BorderColor="LightGray" BorderStyle="None"
                        PageSize="14" OnSorting="GridView1_Sorting" OnRowCommand="GridView1_RowCommand"
                        EmptyDataText="No records found" ShowFooter="True">
                        <Columns>
                            <asp:CommandField HeaderText="Detail" ShowSelectButton="True">
                                <HeaderStyle HorizontalAlign="Center" />
                                <ItemStyle HorizontalAlign="Center" Width="10px" />
                            </asp:CommandField>
                            <asp:BoundField DataField="equipmentID" HeaderText="Equipment ID" SortExpression="equipmentID">
                                <ItemStyle HorizontalAlign="Left" Width="60px" />
                                <HeaderStyle HorizontalAlign="Center" />
                            </asp:BoundField>
                            <asp:BoundField DataField="equipmentname" HeaderText="Equipment Name">
                                <HeaderStyle HorizontalAlign="Center" />
                                <ItemStyle HorizontalAlign="Left" Width="240px" />
                            </asp:BoundField>
                            <asp:BoundField DataField="hours" HeaderText="Hours" NullDisplayText="0">
                                <ItemStyle HorizontalAlign="Right" Width="50px" />
                                <FooterStyle HorizontalAlign="Right" />
                            </asp:BoundField>
                        </Columns>
                        <HeaderStyle BackColor="#FFC080" Height="35px" />
                        <AlternatingRowStyle BackColor="#FFFFC0" />
                        <SelectedRowStyle BackColor="#FF8080" />
                        <EditRowStyle BackColor="#FF8080" />
                        <RowStyle Height="20px" />
                        <FooterStyle BackColor="#FF8080" />
                    </asp:GridView>

Code (markup):

 

The same thing happened for me, when I created a test project in visual studio. I found that if you add the button within the Page_load event and not the Gridview_RowDataBound event, and just use the GridView1.FooterRow reference then it works fine, as i showed in the example in my second post. Is there a problem with using this method? Another solution is to simple add the linkbutton to the footer within the markup.

 

Hi camjohnson95,

Thank you I will let you know. Thanks so much.

 

hi camjohnsosn95,

I tried what you said and have following.

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

        Dim myLinkButton As New LinkButton
        myLinkButton.Text = "Select"
        AddHandler myLinkButton.Click, New EventHandler(AddressOf ClickHandler)
        GridView1.FooterRow.Cells(0).Controls.Add(myLinkButton)
       
End Sub

Code (markup):

Protected Sub GridView1_RowDataBound(ByVal sender As Object, ByVal e As GridViewRowEventArgs) Handles GridView1.RowDataBound

        Dim tabledata As Data.DataRowView = e.Row.DataItem
       
        If e.Row.RowType = DataControlRowType.Footer Then
            e.Row.Cells(2).Text = "Selection Total"
            e.Row.Cells(3).Text = Session("TotalHours")
        End If

End Sub

Code (markup):

Now when I run I get error on"GridView1.FooterRow.Cells(0).Controls.Add(myLinkButton)" -> Object reference not set to an instance of an object. I read that "The FooterRow property is available only after the GridView control creates the footer row in the RowCreated event" (http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview.footerrow(VS.80).aspx)

Any clue what I am doing wrong? Thank you.

 

Hi camjohnson95,

Just about to pull my hair out when I discovered following:

If I put the "footer" code in the GridView1_RowCreated it works. When I click the "select" link button in the footer row, it fires the ClickHandler event.

I guess this means I should be all set, I definitely learned something. Thank you again for all your help.

Protected Sub GridView1_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs) Handles GridView1.RowCreated. 

If e.Row.RowType = DataControlRowType.Header Then
   
        If e.Row.RowType = DataControlRowType.Footer Then
            Dim myLinkButton As New LinkButton
            myLinkButton.Text = "Select"
            AddHandler myLinkButton.Click, New EventHandler(AddressOf ClickHandler)
            e.Row.Cells(0).Controls.Add(myLinkButton)
            e.Row.Cells(2).Text = "Selection Total"
            e.Row.Cells(3).Text = Session("TotalHours")
End If

End Sub

Code (markup):