The following sample demonstrates using the GroupByMode to provide automatic Outlook style grouping for a DateTime field. In addition, the sample also initializes the grid so that it is grouped by the Value field when the application starts. To do this, a FieldSortDescription is added to the SortedFields collection of the FieldLayout. The FieldSortDescription identifies the Name of the field to sort as well as the sort direction and that this field should be grouped by as well.
<igDP:XamDataGrid>
<igDP:XamDataGrid.FieldLayouts>
<igDP:FieldLayout>
<igDP:FieldLayout.Fields>
<igDP:Field Name="Value">
<igDP:Field.Settings>
<igDP:FieldSettings GroupByMode="OutlookDate" />
</igDP:Field.Settings>
</igDP:Field>
</igDP:FieldLayout.Fields>
<igDP:FieldLayout.SortedFields>
<igDP:FieldSortDescription IsGroupBy="True" Direction="Descending" FieldName="Value"/>
</igDP:FieldLayout.SortedFields>
</igDP:FieldLayout>
</igDP:XamDataGrid.FieldLayouts>
<sys:DateTime>2010/7/1</sys:DateTime>
<sys:DateTime>2010/1/1</sys:DateTime>
<sys:DateTime>2005/7/1</sys:DateTime>
<sys:DateTime>2005/1/1</sys:DateTime>
</igDP:XamDataGrid>
