Expands a specified item and, optionally, its children.
- macOS 10.0+
An item in the receiver.
Starting in OS X version 10.5, passing
'nil'will expand each item under the root in the outline view.
true, recursively expands
itemand its children. If
itemonly (identical to
For example, this method is invoked with the
expand parameter set to
true when a user Option-clicks the disclosure triangle for an item in the outline view (to expand the item and all its contained items).
For each item expanded, posts an item expanded notification.