The following exception is observed in certain cases:

at Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.FlatLayoutStrategy.RealizeMergedCells(Double frozenOffset, IEnumerable`1 mergedCells)

at Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.FlatLayoutStrategy.CalculateMergedCells(Boolean shouldInvalidateMeasure)

at Telerik.Windows.Controls.GridView.GridViewVirtualizingPanel.CalculateMergedCells(Boolean shouldInvalidateMeasure)

at Telerik.Windows.Controls.GridView.GridViewCellsPanel.ArrangeOverride(Size finalSize)

When you have rows grouped by null value and you try to move one of the rows to another group, a NullReferenceException is thrown.

This is reproducible only when DataView is used as ItemsSource of RadGridView.

To work this around, avoid using null values. Or avoid using DataView.

Memory leak appears when exporting to Xlsx and Pdf formats.

To work this around, you can call one of the export methods GridViewDataControlExportExtensions with empty arguments.

Workbook workbook = this.gridView.ExportToWorkbook();
try
{
	GridViewDataControlExportExtensions.ExportToWorkbook(new RadGridView(), new GridViewDocumentExportOptions());
	GridViewDataControlExportExtensions.ExportToWorkbook(null);
}
catch (ArgumentException)
{
}