I added an editable grid on my page, based on forum posts I found on this site (see attached images). The grid works as expected; however, the filtering & sorting do not.

In edit mode, the grid has a few drop-down lists using <EditItemTemplate>. Unfortunately, the default filter for these columns ends up being a textbox instead of a drop-down list. How can I change them? Also, these fields lose their sorting capability - the column headers can't be clicked, like the other columns in the grid.

If I change the tag from <EditItemTemplate> to <FilterTemplate> the filter becomes a drop-down list; but, then the fields are no longer listed on the edit screen (see attached image). 

How can I implement a grid that has both capabilities - a drop-down for editing & for filtering?

This is how I've implemented things...

ASPX page

<telerik:RadGrid ID="RadGrid2" RenderMode="Lightweight" runat="server" AutoGenerateColumns="false" AllowSorting="True" AllowPaging="True" ShowStatusBar="true" OnItemDataBound="RadGrid2_ItemDataBound" AllowFilteringByColumn="True" >

    <MasterTableView Name="PlantTypeGrid" DataKeyNames="ID" CommandItemDisplay="Top" ShowFooter="false" >
        <HeaderStyle Font-Bold="true"/>
        <Columns>
            <telerik:GridEditCommandColumn ButtonType="FontIconButton" />
            <telerik:GridCheckBoxColumn DataField="Active" HeaderText="Active" />
            <telerik:GridBoundColumn DataField="Description" HeaderText="Description" AllowFiltering="false" />
            <telerik:GridTemplateColumn HeaderText="Process Unit Category" UniqueName="ProcessUnitCategoryID" AllowFiltering="true" >
                <EditItemTemplate>
                    <telerik:RadDropDownList runat="server" ID="ddlProcessUnitCatTelerik" AppendDataBoundItems="true" >
                    </telerik:RadDropDownList>
                </EditItemTemplate>
            </telerik:GridTemplateColumn>
            <telerik:GridButtonColumn ConfirmText="Delete this Plant Type?" ConfirmDialogType="RadWindow" ConfirmTitle="Delete" CommandName="Delete" ButtonType="FontIconButton" />
        </Columns>
    </MasterTableView>
    <PagerStyle Mode="NextPrevAndNumeric" />
  </telerik:RadGrid>

VB Page

Private Sub BuildPlantTypeGrid()
    Dim myCollection As EMSLookupItems = Nothing
    myCollection = _lookupMgr.GetPlantTypes(-1, -1)
    If Not myCollection.Count = 0 Then
        RadGrid2.DataSource = myCollection.Items
    Else
        RadGrid2.DataSource = ""
    End If
End Sub

Protected Sub RadGrid2_ItemDataBound(ByVal sender As Object, ByVal e As GridItemEventArgs)

    If TypeOf e.Item Is GridEditableItem Then
        If e.Item.IsInEditMode Then
            Dim item As GridEditableItem = CType(e.Item, GridEditableItem)
            Dim mySubCollection As EMSLookupItems = Nothing
            Dim ddlProcessUnitCatTelerik As RadDropDownList = CType(item.FindControl("ddlProcessUnitCatTelerik"), RadDropDownList)
            ddlProcessUnitCatTelerik.Width = Unit.Pixel(300)

            If Not ddlProcessUnitCatTelerik Is Nothing Then
                mySubCollection = _lookupMgr.GetLookupValues("PROCESS_UNIT_CATEGORIES")
                If Not mySubCollection.Count = 0 Then
                    ddlProcessUnitCatTelerik.DataSource = mySubCollection.Items
                    ddlProcessUnitCatTelerik.DataValueField = "ID"
                    ddlProcessUnitCatTelerik.DataTextField = "Description"
                Else
                    ddlProcessUnitCatTelerik.DataSource = ""
                End If
                ddlProcessUnitCatTelerik.DataBind()
                ddlProcessUnitCatTelerik.Items.Insert(0, "Please Select...")
            End If
        End If
    End If
End Sub