Question about programmatic access to Button in Repeater control

[Guest]

Hi,

I have a Repeater control which is bound to a dataset. In the footer of the
repeater control, I have a Button whose visibility I want to vary according
to the sum of a column being > 0.

I have tried to set the button's visibility in Page_Load (after data
binding), but I get a NullReferenceException stating that "Object reference
not set to an instance of an object".

I'm sure this has to do with when my repeater control and it's contained
controls are being rendered, I've tried putting the logic in several places
but I can't figure it out. Below is the code; thank you for any help.

-Keith

==========================================
WebForm.aspx
==========================================
<asp:Repeater id="Repeater1" runat="server">
<HeaderTemplate>
<table>
<tr>
<td>Name</td>
<td>Num Users</td>
</tr>
</HeaderTemplate>
<ItemTemplate>
<tr>
<td><%# DataBinder.Eval(Container.DataItem,"GroupName") %></td>
<td><%# DataBinder.Eval(Container.DataItem,"NumUsers") %></td>
</tr>
</ItemTemplate>
<FooterTemplate>
<tr>
<td>
<asp:Button id="buttonNext" runat="server" Text="Next"
OnClick="buttonNext_Click" Visible="True"></asp:Button>
</td>
</tr>
</table>
</FooterTemplate>

==========================================
WebForm.aspx.cs
==========================================
....
protected System.Web.UI.WebControls.Repeater Repeater1;
protected System.Web.UI.WebControls.Button buttonNext;
....
private void Page_Load(object sender, System.EventArgs e)
{
this.Repeater1.DataSource=dsDataSet;
this.Repeater1.DataBind();

object
sum=dsDataSet.Tables[0].Compute("SUM(NumUsers)","NumUsers=NumUsers");

buttonNext.Visible=( (int)sum > 0 );
}

 

[Justin Rogers]

There are events for this sort of thing, like ItemCreated... Where you can
access your e.Item and then go look for controls on it.