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void CBCGPGanttItem::SetGroupItem ( BOOL  bGroup = TRUE)

Sets an item to be a group item.

Use this function to define an item as a group item. This is required to define an hierarchy of items, when a group item represents an interval that covers all sub items.

A sub-item's offset within the hierarchy is defined by a "hierarchy level". The hierarchy level for a group item is 0.

bGroupSpecifies whether an item is a group item (TRUE) , or not (FALSE).