constants DrawPartEnum
The DrawPartEnum type specifies the identifier of parts that can be overridden using the BeforeDrawPart and AfterDrawPart events. Currently, the supported values are:

NameValueDescription
exOwnerDrawBar0 Specifies that the "OwnerDraw" bar is drawing. Use the Add or Copy method to add a "OwnerDraw" bar. The DrawPartItem property specifies the handle of the item that hosts the "OwnerDraw" bar. The DrawPartKey property specifies the key of the bar to be painted. Use the ItemBar(DrawPartItem,DrawPartKey) property to access properties of the drawing bar. 
exDrawLeftHistogram1 Specifies the left part of the histogram. The area is shown in the histogram part just bellow the list/items area. Use the HistogramRulerLinesColor property to automatically show the ruler in the left part of the histogram. Use the HistogramCumulativeShowLegend property to automatically show the legend for items being included in the histogram when cumulative colors are shown.  The control fires the HistogramBoundsChanged event when the bound of the left histogram part is changed, so you can automatically updates the position for inside controls if you display them on the histogram part. 
exDrawRightHistogram2 Specifies the right part of the histogram. The area is shown in the histogram part just bellow the chart area. The right part of the histogram shows the chart's histogram when HistogramVisible property is True and the HistogramPattern or/and HistogramColor property is set.