DataBinding: System.Data.DataRowView doesn't contain a property with the name 'ProductID'

I followed the walkthrough at http://msdn.microsoft.com/en-us/library/dd381611%28VS.100%29.aspx. But I got an error when switch to the design view. The error message is
DataBinding: System.Data.DataRowView doesn't contain a property with the name 'ProductID'
My code:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="ProductList.aspx.cs" Inherits="ProductList" %> <!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:SqlDataSource ID="SqlDataSource1" runat= ...