Use the BackColorHeader and ForeColorHeader properties to define colors used to paint the group's header bar. Use the BackColorLevelHeader property to specify the background color of the group's header bar when multiple levels are displayed. Use the LevelKey property to display the group's header bar using multiple levels. If the control displays the header bar using multiple levels the HeaderHeight property gets the height in pixels of a single level in the header bar. The group's header displays multiple levels if there are two or more neighbor columns with the same non empty level key.