Problem with filtering and GroupByExpression

[Ferdinand]

Hi there.
I have the following grid:

<telerik:RadGrid ID="RadGrid1" runat="server" AllowPaging="True" AllowSorting="True" AllowFilteringByColumn="true"
    GridLines="None" Width="100%" DataSourceID="ObjectDataSource1" meta:resourcekey="RadGrid1Resource1"
    OnItemDataBound="RadGrid1_ItemDataBound">
    <ClientSettings AllowColumnsReorder="True" ReorderColumnsOnClient="True">
        <Selecting AllowRowSelect="True" />
    </ClientSettings>
    <PagerStyle Mode="NextPrevNumericAndAdvanced" AlwaysVisible="true" />
    <MasterTableView AutoGenerateColumns="False" DataSourceID="ObjectDataSource1">
        <Columns>
            <telerik:GridTemplateColumn meta:resourcekey="GridTemplateColumnResource1" UniqueName="TemplateColumn" AllowFiltering="false">
                <ItemTemplate>
                    <a href="Rightdata.aspx" onclick='openDataWindow('RightData.aspx?id=<%# Eval("ID") %>', 'RadWindow1'); return false;'>
                        <img alt="bearbeiten" style="border: 0;" src="img/scroll2_edit_24.png" title="bearbeiten" />
                    </a>
                    <asp:ImageButton ID="ImageButton2" runat="server" CommandArgument='<%# Eval("ID") %>'
                        CommandName="Delete" ImageUrl="img/scroll2_delete_24.png" meta:resourcekey="ImageButton2Resource1"
                        OnClick="ImageButton2_Click" />
                </ItemTemplate>
                <ItemStyle CssClass="style1" />
            </telerik:GridTemplateColumn>
            <telerik:GridBoundColumn DataField="Name" HeaderText="Anzeigename" meta:resourcekey="GridBoundColumnResource1"
                SortExpression="Name" UniqueName="Name">
                <ItemStyle CssClass="style2" />
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="UniqueName" HeaderText="UniqueName" meta:resourcekey="GridBoundColumnResource2"
                SortExpression="UniqueName" UniqueName="UniqueName">
                <ItemStyle CssClass="style2" />
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn DataField="Description" HeaderText="Beschreibung" meta:resourcekey="GridBoundColumnResource3"
                SortExpression="Description" UniqueName="Description">
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn AllowSorting="False" DataField="ParentCategory" HeaderText="überg. Kategorie"
                meta:resourcekey="GridBoundColumnResource4" UniqueName="Category">
            </telerik:GridBoundColumn>
            <telerik:GridBoundColumn AllowSorting="False" DataField="Category" HeaderText="Kategorie"
                meta:resourcekey="GridBoundColumnResource5" UniqueName="Category">
            </telerik:GridBoundColumn>
        </Columns>
        <GroupByExpressions>
            <telerik:GridGroupByExpression>
                <SelectFields>
                    <telerik:GridGroupByField FieldAlias="Kategorie" FieldName="ParentCategory" FormatString=""
                        HeaderText="" meta:resourcekey="GridGroupByFieldResource1" />
                </SelectFields>
                <GroupByFields>
                    <telerik:GridGroupByField FieldAlias="ParentCategory" FieldName="ParentCategory"
                        meta:resourcekey="GridGroupByFieldResource2" />
                </GroupByFields>
            </telerik:GridGroupByExpression>
            <telerik:GridGroupByExpression>
                <SelectFields>
                    <telerik:GridGroupByField FieldAlias="Unterkategorie" FieldName="Category" FormatString=""
                        HeaderText="" meta:resourcekey="GridGroupByFieldResource3" />
                </SelectFields>
                <GroupByFields>
                    <telerik:GridGroupByField FieldAlias="Category" FieldName="Category" meta:resourcekey="GridGroupByFieldResource4" />
                </GroupByFields>
            </telerik:GridGroupByExpression>
        </GroupByExpressions>
    </MasterTableView>
</telerik:RadGrid>

If I turn on the AllowFilteringByColumn property the following error occurs:
Multiple controls with the ID FilterTyexBox_Category found. FindControl requires that controls have unique IDs.

What did I miss?

[Martin]

Hello Ferdinand,

As the exception states, your grid contains two columns with the same UniqueName set. Here is a small excerpt from your code:

<telerik:GridBoundColumn AllowSorting="False" DataField="ParentCategory" HeaderText="überg. Kategorie"
    meta:resourcekey="GridBoundColumnResource4" UniqueName="Category">
</telerik:GridBoundColumn>
<telerik:GridBoundColumn AllowSorting="False" DataField="Category" HeaderText="Kategorie"
    meta:resourcekey="GridBoundColumnResource5" UniqueName="Category">

Please change one of the highlighted unique names above and verify whether the problem still exists.

I hope this helps.

Greetings,
Martin
the Telerik team