Returns the index of the item at the specified location.
Original signature is '- (NSInteger)indexOfItemAtPoint:(NSPoint)point'
Available in Mac OS X v10.5 and later.


- point (NSPoint)
- The location of the item.

The index of the item or NSNotFound if no item at this location.

- Available in Monobjc Bridge: 10.6 (For Mac OS X 10.6 and later), 10.5 (For Mac OS X 10.5 and later)