Gets the index and relative place in the collection that an object is being dropped over.
A drop-object , as passed to the drop-callback .
returns the index and place relative to that index within the collection that the object
is being dropped over. This information is only meaningful when the pane is an instance of list-panel or tree-view.
The returned value index is the position in the collection (see get-collection-item or choice-selection). The returned value placement indicates whether the user is dropping above, on or below the item at index .
should only be called within a
. It is not supported on X11/Motif. See simple-pane for information about drop callbacks.
For an example illustrating the use of drag and drop in a choice, see