When adding a filter to the DataGrid programmatically, the filter descriptor values are not shown in the filter UI and the header icons are not visible.

Filtering UI can be customized through the FilterControlTemplate property of the DataGridColumn: DataGrid: FilterControl Template.

We should provide a way to customize the Grouping UI including the Visible Columns area.

My mobile app requires that my data grid have frozen columns on the left that do NOT scroll horizontally.  This is useful when the first column might be an ID column or a Date column that the user always needs to see when scrolling through the other data columns.

Currently the DataGrid uses a GroupDescriptorCollection type for GroupDescriptors, which is not bindable (even with OneWayToSource mode).

The same holds true for the Filter and Sort collections.

It would be nice to follow the same paradigm as the completed RadListView feedback item here: https://feedback.telerik.com/Project/168/Feedback/Details/211065-listview-make-groupdescriptors-sortdescriptors-and-filterdescriptors-collection