Occurs before a group row is collapsed.
public event RowAllowEventHandler GroupRowCollapsing
Public Event GroupRowCollapsing As RowAllowEventHandler
The GroupRowCollapsing event is raised before a group row is collapsed by an end-user or in code, allowing you to cancel this action. To prevent a group row from being collapsed, set the event parameter's Allow property to false.
The GridControl.CollapseAllGroups method allows you to collapse all group rows. In this instance, the GroupRowCollapsing event is raised for each group.
After the group row has been collapsed, the GridControl.GroupRowCollapsed event is raised.