Programmatically Bind Formview Based on Dropdownlist Selected

[Goku San]

I have the following Formview:

01.<asp:FormView runat="server" ID="fv1" PagerSettings-Visible="False"
02.                  EmptyDataText="No Image Set Found." EnableViewState="False"
03.                  AllowPaging="True">
04.                <ItemTemplate>
05.                  <asp:Button ID="btnUpdate" runat="server" CommandName="Update" Text="Edit" />
06.                </ItemTemplate>
07.                <EditItemTemplate>
08.                  <br />
09.                  <asp:Label ID="lbl0" runat="server" Visible="False" Text="Or choose one from the list:">
10.                  </asp:Label>
11.                  <asp:TextBox ID="txt0" runat="server"
12.                    Text='<%# Bind("Field0") %>'></asp:TextBox>
13.                  <asp:RequiredFieldValidator ID="rfv0" runat="server" ErrorMessage="* Required" ControlToValidate="txt0" SetFocusOnError="True" CssClass="error"></asp:RequiredFieldValidator>
14. 
15.                </EditItemTemplate>
16.                <PagerSettings Visible="False" />
17.                </asp:FormView>

I have the following dropdownlist outside of the formview:

1.<asp:DropDownList ID="ddl0" runat="server" Visible="false"
2.  AutoPostBack="true" SkinID="DropDownList" AppendDataBoundItems="true" >
3.</asp:DropDownList>

What I would like to happen, is when the user chooses an item from the dropdown list, it shows all the values for that particular chosen record in the formview's controls. I would like this to work as a partial postback. Currently, I have one control in the formview, however, I plan on adding more once i know this works. The datasource for the dropdown is a table programmaticly assigned during the page's load event after, If Not Page.IsPostBack code. Then the dropdown's source is programmaticly assigned to the formview's source:

Code-Behind in VB:

01.ddl0.DataSource = imgTable
02.ddl0.DataTextField = "Name"
03.ddl0.DataValueField = "tableIndex"
04.ddl0.DataBind()
05.ddl0.Visible = True
06. 
07.fv1.DataSource = ddl0.DataSource
08.fv1.DataBind()

This works during the page's first time load. However, once I change the dropdown to something different and the page refreshes, the textbox in the formview disappears. When I debug, I notice the dropdown and formview will lose their datasource values. Not sure why. I imagine, it has something to do with postbacks.

I pulled the data from a SQL database using a SELECT command. Stored it in a Dataset. Pulled out the table and assigned it to variable of type DataTable called imgTable. imgTable gets assigned to the datasource of the DropDownList. The DropDownList's datasource gets assigned to the formview's datasource. I have it this way because they pull the same data, and 2, whatever selection changes in the dropdown should be reflected in the controls of the formview.
Now my PageLoad looks like:

01.Protected Sub Page_Load(sender As Object, e As System.EventArgs) Handles Me.Load
02. 
03.  If Not Page.IsPostBack Then
04.    lblMsg.Visible = False
05.
      fetchdata() 'Function to get the data from the SQL database.
06.      BindData() 'Function to bind data to all page controls.
07.  Else
08.    If Not lblMsg.Text = "" Then
09.      lblMsg.Visible = True
10.    End If
11.    fv1.DefaultMode = FormViewMode.Edit
12.  End If
13.  fv1.DataSource = imgTable
14.  fv1.DataBind()
15.
End Sub

It still doesn't work though. Instead, the textbox in the formview, displays the EmptyDataText value when I change values for my DropDownList.

Thanks,
Andy