Gridview Update Problem

[functionalCode]

Hey everyone I am trouble getting a reference to dropdownlist1. I need to get the selectedvalue so I can use the sqldatasource to update the table in my database. How can I get a reference to dropdownlist1. I have used Page.FindControl(), but I still am getting a null pointer exception.

Thanks

Here is the code:

<asp:GridView ID="GridView1" runat="server" AllowPaging="True" 
                AutoGenerateColumns="False" DataSourceID="SqlDataSource2" 
                Width="886px" style="margin:auto;" CellPadding="4" ForeColor="#333333" 
            GridLines="None" DataKeyNames="UserID" 
            onrowupdating="GridView1_RowUpdating" >
                <AlternatingRowStyle Font-Names="Calibri" Height="5" BackColor="White" />
                <Columns>
                    <asp:CommandField ShowEditButton="True" />
                    <asp:BoundField DataField="UserID" HeaderText="UserId" SortExpression="UserId" 
                        Visible="False" />
                    <asp:BoundField DataField="FirstName" HeaderText="First Name" 
                        SortExpression="FirstName" />
                    <asp:BoundField DataField="ListName" HeaderText="Last Name" 
                        SortExpression="ListName" />
                    <asp:BoundField DataField="UserName" HeaderText="User Name" 
                        SortExpression="UserName" />
                    <asp:TemplateField HeaderText="Role Name" SortExpression="RoleName">
                        <EditItemTemplate>
                            <asp:DropDownList ID="DropDownList1" runat="server" 
                                DataSourceID="SqlDataSource1" DataTextField="RoleName" 
                                DataValueField="RoleID" AutoPostBack="True">
                            </asp:DropDownList>
                            <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
                                ConnectionString="<%$ ConnectionStrings:AdvisementDB %>" 
                                SelectCommand="sp_getRoles" SelectCommandType="StoredProcedure" >
                            </asp:SqlDataSource>
                        </EditItemTemplate>
                        <ItemTemplate>
                            <asp:Label ID="Label1" runat="server" Text='<%# Bind("RoleName") %>'></asp:Label>
                        </ItemTemplate>
                    </asp:TemplateField>
                    <asp:BoundField DataField="StudentID" HeaderText="Student ID" 
                        SortExpression="StudentID" />
                    <asp:BoundField DataField="LastActivityDate" HeaderText="Last Activity Date" 
                        SortExpression="LastActivityDate" />
                </Columns>
                <EditRowStyle BackColor="#2461BF" />
                <FooterStyle BackColor="#507CD1" Font-Bold="True" ForeColor="White" />
                <HeaderStyle Font-Names="Calibri" BackColor="#507CD1" Font-Bold="True" 
                    ForeColor="White" />
                <PagerStyle BackColor="#2461BF" ForeColor="White" HorizontalAlign="Center" />
                <RowStyle Height="5px" BackColor="#EFF3FB" />
                <SelectedRowStyle BackColor="#D1DDF1" Font-Bold="True" ForeColor="#333333" />
                <SortedAscendingCellStyle BackColor="#F5F7FB" />
                <SortedAscendingHeaderStyle BackColor="#6D95E1" />
                <SortedDescendingCellStyle BackColor="#E9EBEF" />
                <SortedDescendingHeaderStyle BackColor="#4870BE" />
            </asp:GridView>

[Knvn]

In the GridView1_RowCommand event, you have to use

DropDownList ddl = (DropDownList)GridView1.Rows[Convert.ToInt32(e.CommandArgument)].FindControl("DropDownList1");