grid grouping question

[Steven]

I've got the following grid with grouping setup. I'd like it so that they can't remove the category group but can add and remove the other 3 .

Is that possible?   thanks

<telerik:RadGrid ID="RadGrid1"  runat="server" PageSize="50"
    AllowSorting="True" AllowMultiRowSelection="True" AllowPaging="false" ShowGroupPanel="True" OnPageIndexChanged="RadGrid1_OnPageIndexChanged"
    AutoGenerateColumns="False" GridLines="none" OnNeedDataSource="RadGrid1_OnNeedDataSource">
    <PagerStyle Mode="NextPrevNumericAndAdvanced"></PagerStyle>
    <MasterTableView Width="100%" >
        <GroupByExpressions >

            <telerik:GridGroupByExpression >
            <SelectFields>
                <telerik:GridGroupByField FieldAlias="Category" FieldName="Category"  />
            </SelectFields>
                <GroupByFields>
                    <telerik:GridGroupByField FieldName="Category"  SortOrder="Ascending"    />
                </GroupByFields>
            </telerik:GridGroupByExpression>
        </GroupByExpressions>
        <Columns>
            <telerik:GridBoundColumn SortExpression="PatientName" HeaderText="PatientName" HeaderButtonType="TextButton" DataField="PatientName"  Groupable="false"  />
            <telerik:GridBoundColumn SortExpression="Category" HeaderText="Category" HeaderButtonType="TextButton"  DataField="Category"  />
            <telerik:GridBoundColumn SortExpression="LastTaskTime"  HeaderText="LastTaskTime" HeaderButtonType="TextButton" DataField="LastTaskTime"  />
            <telerik:GridBoundColumn SortExpression="CaseStatus" HeaderText="CaseStatus" HeaderButtonType="TextButton" DataField="CaseStatus" />
        </Columns>
    </MasterTableView>
    <ClientSettings ReorderColumnsOnClient="True" AllowDragToGroup="True" AllowColumnsReorder="True" >
        <Selecting AllowRowSelect="True" ></Selecting>
        <Resizing AllowRowResize="True" AllowColumnResize="True" EnableRealTimeResize="True"
            ResizeGridOnColumnResize="False"></Resizing>
    </ClientSettings>
    <GroupingSettings ShowUnGroupButton="false">

    </GroupingSettings>
</telerik:RadGrid>

[Radoslav]

Hello Steven,

To achieve the desired functionality you could try handling the RadGrid.GroupsChanging event and cancel it if the group by field is Category:

protected override void OnInit(EventArgs e)
    {
        base.OnInit(e);

        RadGrid1.GroupsChanging += RadGrid1_GroupsChanging;
    }

    void RadGrid1_GroupsChanging(object sender, GridGroupsChangingEventArgs e)
    {
        if (e.Expression.GroupByFields[0].FieldName == "Category")
        {
            e.Canceled = true;
        }
    }

Additionally I am sending you a simple example which demonstrates the suggested approach. Please check it out and let me know if it helps you.

Kind regards,
Radoslav
the Telerik team