Hide Group Header for Hidden Column

[Amy]

Hi there,

I have a gridview with two columns - CAD Amount and USD Amount - that I hide/display based on a radiobutton choice.  In the grid, when a user groups by another column Employee, I display the sum of the CAD Amount and USD Amount in the group header.  Currently, both aggregate values are displayed even if only one of the CAD Amount or USD Amount columns is visible.   However, I would only like to display the sum for the column in the header if the column is visible.  Is this possible?

Here is the XAML code:

<telerik:RadGridView x:Name="CostDetailsGridView"
                                 Width="594"
                                 Height="370"
                                 IsReadOnly="True"
                                 AutoGenerateColumns="False"
                                 ShowColumnFooters="True"
                                 ShowGroupFooters="True">
                <telerik:RadGridView.Columns>
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding PostingDate}" DataFormatString="{}{0:d}" Header="Posting Date" />
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding AmountCAD}" Header="Amount (in CA$)" TextAlignment="Right" FooterTextAlignment="Right" DataFormatString="{}{0:c0}" IsGroupable="False">
                        <telerik:GridViewDataColumn.AggregateFunctions>
                            <telerik:SumFunction SourceField="AmountCAD" ResultFormatString="{}{0:c0}" />
                        </telerik:GridViewDataColumn.AggregateFunctions>
                    </telerik:GridViewDataColumn>
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding AmountUSD}" Header="Amount (in US$)" TextAlignment="Right" FooterTextAlignment="Right" DataFormatString="{}{0:c0}" IsGroupable="False" IsVisible="False">
                        <telerik:GridViewDataColumn.AggregateFunctions>
                            <telerik:SumFunction SourceField="AmountUSD" ResultFormatString="{}{0:c0}" />
                        </telerik:GridViewDataColumn.AggregateFunctions>
                    </telerik:GridViewDataColumn>
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding Employee}" Header="Employee" />
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding Department}" Header="Department" />
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding Reimbursement}" Header="Reimbursement" />
                    <telerik:GridViewDataColumn DataMemberBinding="{Binding ExpenseType}" Header="Expense Type" />
                </telerik:RadGridView.Columns>
                <telerik:RadGridView.GroupDescriptors>
                    <telerik:GroupDescriptor Member="Employee" DisplayContent="Employee" SortDirection="Ascending"/>
                </telerik:RadGridView.GroupDescriptors>
            </telerik:RadGridView>

Thanks,
Amy

[Dimitrina]

Hi Amy,

If you want to not include some AggregateFunction in a GroupFooter, you will need to manually remove it from the collection of AggregateFunctions associated to the GroupDescriptor. You may do this in the DataLoaded event of the GridView only the first time when it is raised. Once the event is raised, you will need to unsubscribe from it.

In the DataLoaded event you find all the AggregateFunctions of the invisible columns. Then you remove them from the GroupDecriptor like this:

this.clubsGrid.DataLoaded += new EventHandler<EventArgs>(clubsGrid_DataLoaded);

void clubsGrid_DataLoaded(object sender, EventArgs e)
        {
            this.clubsGrid.DataLoaded -= new EventHandler<EventArgs>(clubsGrid_DataLoaded);

            var functionsToRemove = this.clubsGrid.Columns
                .OfType<GridViewDataColumn>()
                .Where(c => c.IsVisible == false)
                .SelectMany(c => c.AggregateFunctions);

            if (this.clubsGrid.GroupDescriptors.Count > 0)
            {
                foreach (var item in functionsToRemove)
                {
                    (this.clubsGrid.GroupDescriptors[0] as GroupDescriptor).AggregateFunctions.Remove(item);
                }
            }
        }

Once you change the column to be visible again, you have to add its AggregateFunctions to the GroupDescriptor.

Is this workaround appropriate for your project.

Greetings,
Didie
the Telerik team