Declares the types of operations the source allows to be performed.
- macOS 10.7+
The dragging session.
The dragging context. See
NSDraggingfor the supported values.
The appropriate dragging operation as defined in
In the future Apple may provide more specific "within" values in the future. To account for this, for unrecognized localities, return the operation mask for the most specific context that you are concerned with. The following code is an example of how to implement this functionality: