Asks the delegate to allow or prohibit the specified column to be dragged to a new location.
- macOS 10.6+
The table view that sent the message.
The index of the column being dragged.
The proposed target index of the column.
YES if the column reordering should be allowed, otherwise
When a column is initially dragged by the user, the delegate is first called with a
new value of
NO will disallow that column from being reordered at all. Returning
YES allows it to be reordered, and the delegate will be called again when the column reaches a new location.
If this method isn’t implemented, all columns are considered reorderable.