How do I drag and drop into an NSOutlineView without specifying the row location?

Question

I'm pretty new to Cocoa, and I'm developing an application that does drag/drop from and into NSOutlineView.

I've implemented "outlineView:validateDrop:proposedItem:proposedChildIndex", and "outlineView:acceptDrop:item:childIndex:" methods to make an NSOutlineView a destination for dropping. It works all fine, except that it tries to specify a row/location into which the items from a different NSOutlineView should be dropped.

My application doesn't really need to specify which row the item should be dropped on or above; ideally, I would like to have the entire NSOutlineView box highlighted when I drag-and-drop onto the NSOutlineView. Row selection will be done programmatically.

How can I accomplish this?

Answer 1

You're going to want to use NSOutlineView's setDropItem:dropChildIndex: to programmatically set the index to insert at.

For highlighting the entire outline view, you may want to try NSTableView's setDropRow:dropOperation: setting the dropRow at -1, which the doc says:

Passing a value of –1 for row, and NSTableViewDropOn as the operation causes the entire table view to be highlighted rather than a specific row. This is useful if the data displayed by the receiver does not allow the user to drop items at a specific row location.

NSOutlineView inherits from NSTableView, so this might work if the NSOutlineView subclass doesn't screw up the highlighting behavior of NSTableView.