Group footer label?

[MC]

How can I insert text in a group footer's cell?

 

01.public MainWindow()
02.{
03.    InitializeComponent();
04.
05.    var style = new Style();
06.    style.Setters.Add(new Setter(GroupHeaderRow.ShowGroupHeaderColumnAggregatesProperty, false));
07.    style.Setters.Add(new Setter(GroupHeaderRow.ShowHeaderAggregatesProperty, false));
08.    var radGrid = new RadGridView { GroupRenderMode = GroupRenderMode.Flat, GroupRowStyle = style};
09.    Content = radGrid;
10.
11.    // Table schema
12.    var data = new DataTable();
13.    var user = data.Columns.Add("User");
14.    var cat = data.Columns.Add("Category");
15.    var amt = data.Columns.Add("Amount", typeof(decimal));
16.
17.    // Populate values
18.    var catValues = new[] {"Cat A", "Cat B", "Cat C"};
19.    for (var i = 0; i < 20; i++)
20.    { data.Rows.Add("User " + i, catValues[i % catValues.Length], i * 100d); }
21.
22.    // Prepare RadGridView
23.    radGrid.ItemsSource = data;
24.    radGrid.AutoExpandGroups = true;
25.    radGrid.ShowColumnFooters = true;
26.    radGrid.AutoGenerateColumns = false;
27.
28.    // Build RadGrid columns
29.    var gridColumns = new[] {user, cat, amt}
30.        .Select(dataColumn => new GridViewDataColumn
31.        {
32.            UniqueName = dataColumn.ColumnName,
33.            DataMemberBinding = new Binding(dataColumn.ColumnName),
34.        })
35.        .ToList();
36.    radGrid.Columns.AddRange(gridColumns);
37.
38.    // Sum Amount
39.    var amtCol = gridColumns.Last();
40.    var amtFormat = "{0:C}";
41.    amtCol.DataFormatString = amtFormat;
42.    amtCol.AggregateFunctions.Add(new SumFunction()
43.    {
44.        SourceField = amt.ColumnName,
45.        SourceFieldType = amt.DataType,
46.        ResultFormatString = amtFormat
47.    });
48.    radGrid.ShowGroupFooters = true;
49.
50.    // Group by category
51.    var catGroup = new GroupDescriptor { Member = cat.ColumnName, };
52.    radGrid.GroupDescriptors.Add(catGroup);
53.
54.    // Show grand total label
55.    radGrid.Columns[0].Footer = "Grand Total";
56.
57.    // todo: How to show group subtotal label?
58.
59.}

[MC]

ok, I've made some progress by using AggregateFunction and a custom AggregationExpression.

But I'm now having problem when I have nested groupings.

Please see the code and screenshots

public MainWindow()
{
    InitializeComponent();

    var style = new Style();
    style.Setters.Add(new Setter(GroupHeaderRow.ShowGroupHeaderColumnAggregatesProperty, false));
    style.Setters.Add(new Setter(GroupHeaderRow.ShowHeaderAggregatesProperty, false));
    var radGrid = new RadGridView {GroupRenderMode = GroupRenderMode.Flat, GroupRowStyle = style};
    Content = radGrid;

    // Table schema
    var data = new DataTable();
    var dbUser = data.Columns.Add("User");
    var dbType = data.Columns.Add("Type");
    var dbCategory = data.Columns.Add("Category");
    var dbAmt = data.Columns.Add("Amount", typeof(decimal));

    // Populate values
    var categories = new[] {"Cat A", "Cat B", "Cat C"};
    var types = new[] {"Trial", "Full"};
    for (var i = 0; i < 20; i++)
    {
        data.Rows.Add(
            "User " + i,
            types[i % types.Length],
            categories[i % categories.Length],
            i * 100d);
    }

    // Prepare RadGridView
    radGrid.ItemsSource = data;
    radGrid.AutoExpandGroups = true;
    radGrid.ShowColumnFooters = true;
    radGrid.AutoGenerateColumns = false;

    // Build RadGrid columns
    var gridColumns = new[] {dbUser, dbType, dbCategory, dbAmt}
        .Select(dataColumn => new GridViewDataColumn
        {
            UniqueName = dataColumn.ColumnName,
            DataMemberBinding = new Binding(dataColumn.ColumnName),
        })
        .ToList();
    radGrid.Columns.AddRange(gridColumns);

    // Sum Amount
    var amtCol = gridColumns.Last();
    var amtFormat = "{0:C}";
    amtCol.DataFormatString = amtFormat;
    amtCol.AggregateFunctions.Add(new SumFunction()
    {
        SourceField = dbAmt.ColumnName,
        SourceFieldType = dbAmt.DataType,
        ResultFormatString = amtFormat
    });
    radGrid.ShowGroupFooters = true;

    // Show grand total label
    radGrid.Columns[0].Footer = "Grand Total";

    // Nested grouping
    var groupColumns = new[] {
        dbCategory,
        dbType
    };
    foreach (var group in groupColumns)
    {
        var colGroup = new GroupDescriptor {Member = group.ColumnName,};
        radGrid.GroupDescriptors.Add(colGroup);

        // Add text to the first column
        // =============================================================
        // (todo) help: Ends up adding 1 function for each nesting level
        var firstColumn = gridColumns.First();
        firstColumn.AggregateFunctions.Add(new AggregateFunction<DataRow, string>
        {
            AggregationExpression = (rows) => $"{rows.First()[group.ColumnName]} subtotal"
        });
    }
}

[Dilyan Traykov]

Hello,

I'm attaching a sample project based on the code you provided where I've achieved the desired behavior by creating a DataTemplateSelector and defining it as the GroupFooterTemplateSelector for the first column. Inside the selector, I get ahold of the row's group like so:

public class MyGroupFooterTemplateSelector : DataTemplateSelector
{
    public override DataTemplate SelectTemplate(object item, DependencyObject container)
    {
        var template = new DataTemplate();
        var row = (container as GridViewGroupFooterCell).ParentRow as GridViewGroupFooterRow;
        var groupName = (row.Group as CollectionViewGroup).Name;
        var textBlock = new FrameworkElementFactory(typeof(TextBlock));
        textBlock.SetValue(TextBlock.TextProperty, groupName + " subtotal");
        template.VisualTree = textBlock;
        template.Seal();
        return template;
    }
}

Please let me know whether such an approach would be suitable for you.

Regards,
Dilyan Traykov
Telerik by Progress

[MC]

Hi Dilyan,

Thanks for the reply. Your solution did the trick.

Thanks

Josh