By default, the SelectOnClick property is True. By default, the item being clicked gets selected no matter of what part of the control is clicked: list or chart area. Use the SelectOnClick property to disable selecting new items when the user clicks the chart area. The SingleSel property specifies whether the control supports multiple selection. For instance, this property can be useful once you use the HistogramView property on exHistogramSelectedItems ( so the selected items are displayed in the histogram ). User may click the chart area, so new bars are created or creating new links, without changing the selection and so the items being displayed in the histogram.