A parent item can be located at any level. In order to become a parent item, an item has to have one or more dependents, which are items that immediately follow the parent item and are on a lower level. A parent item may be expanded and collapsed using the Item.Expand and Item.Collapse methods. Expanding a parent item means making its immediate dependents (dependents on the next lower level) visible. Collapsing a parent item means hiding all its dependents (on all lower levels). Parent items may have sibling and parent items.
Parent items can be expanded and collapsed using the Item.Expand and Item.Collapse methods.
An item can be marked expandable using the Item.Expandable property, even if it has no child items.