Represents a base class for types defining grouping conditions.
The concrete class which is commonly used for this purpose is PropertyGroupDescription.
groupNameFromItem(item: any, level: number): any
Returns the group name for the given item.
The item to get group name for.
The zero-based group level index.
namesMatch(groupName: any, itemName: any): boolean
Returns a value that indicates whether the group name and the item name match (which implies that the item belongs to the group).
The name of the group.
The name of the item.
