Informs the combo box that the number of items in its data source has changed.
- macOS 10.0+
This method allows the combo box to update the scrollers in its displayed pop-up list without actually reloading data into the combo box. It is particularly useful for a data source that continually receives data in the background over a period of time, in which case the
NSCombo can remain responsive to the user while the data is received.
See the NSComboBoxCellDataSource informal protocol specification for information on the messages an
NSCombo sends to its data source.