private void GridTimeMeasurements_CheckEdit_Unchecked(object sender, RoutedEventArgs e)
        {
            this.Cursor = Cursors.Wait;

            // Unmark
            for (int i = 0; i < GridTimeMeasurements.VisibleRowCount; i++)
            {
                int rowHandle = GridTimeMeasurements.GetRowHandleByVisibleIndex(i);

                GridTimeMeasurements.SetCellValue(rowHandle, GridTimeMeasurements.Columns["marked"], false);
            }

            GridTimeMeasurements.RefreshData();

            this.Cursor = Cursors.Arrow;
        }
        private void GridTimeMeasurements_CheckEdit_Checked(object sender, RoutedEventArgs e)
        {
            this.Cursor = Cursors.Wait;

            // Clear marked flag
            DataTable _dt = (DataTable)GridTimeMeasurements.DataSource;

            foreach (DataRow _dr in _dt.Rows)
            {
                _dr["marked"] = false;
            }

            for (int i = 0; i < GridTimeMeasurements.VisibleRowCount; i++)
            {
                int rowHandle = GridTimeMeasurements.GetRowHandleByVisibleIndex(i);

                GridTimeMeasurements.SetCellValue(rowHandle, GridTimeMeasurements.Columns["marked"], true);
            }

            GridTimeMeasurements.RefreshData();

            this.Cursor = Cursors.Arrow;
        }