Turns icon_view into a drag source for automatic DND. Calling this method sets "reorderable" to FALSE. Since 2.8
Mask of allowed buttons to start drag
the table of targets that the drag will support. [array length=n_targets]
the bitmask of possible actions for a drag from this widget
See Implementation
Turns icon_view into a drag source for automatic DND. Calling this method sets "reorderable" to FALSE. Since 2.8