Grouping by 3 columns, but showing sum of another columsn only once

[Vivido]

Hi all,
I'm building a grid where I group my data by 3 columns, but I show the sum of another column as ClientGroupFooterTemplate. Here some code snippet
Inside data source:
                .Group(gr =>
                    {
                        gr.Add(p=> p.Finality);
                        gr.Add(p=> p.Task);
                        gr.Add(p=> p.Session);
                    }
                )
                .Aggregates(aggr =>
                    {
                        aggr.Add(p => p.Duration).Sum();
                    })

Inside .Columns

//previous columns code
columns.Bound(c => c.Duration).Title("Duration (h)").Width(150).ClientGroupFooterTemplate("Sum: #=sum#");
//following columns code

but when grid displays the data it shows the Sum at the end of every grouping (Finality, Task and Session)
I want to diplay it only for Session, how can I accomplish that?

[Daniel]

Hello,

This is not supported by the grid. The template will be rendered for each group. It should be possible to use a condition that checks if the template is rendered for the Session group and show the value only in this case. If you are using server side operations then this can be achieved by checking the template item parent e.g.

.ClientGroupFooterTemplate("#: sessionFooter(data)#")

function sessionFooter(data) {
    if (data.parent().field == "Session") {
        return "Sum: " + data.Duration.sum;
    }

    return "";
}

For client-side operations you will need to iterate over the summary group items in the dataSource change or in the grid dataBinding events and set a a field that indicates whether the value should be rendered to the Duration aggregates.

Regards,
Daniel
Telerik