The object that provides the data displayed by the receiver.
- macOS 10.6+
The object must implement the appropriate methods of
NSOutline. See Writing an Outline View Data Source and the NSOutlineViewDataSource Protocol informal protocol specification for more information. Note that in versions of macOS prior to v10.12, the outline view did not retain the data source in a managed memory environment.
Setting the data source invokes
If the data source doesn’t respond to all of the
outline methods, an
internal may be raised.