Cancels an ongoing drag operation on the source side.
If you want to be able to cancel a drag operation in this way,
you need to keep a pointer to the drag context, either from an
explicit call to gtk.widget.Widget.dragBeginWithCoordinates, or by
connecting to #GtkWidget::drag-begin.
If context does not refer to an ongoing drag operation, this
function does nothing.
If a drag is cancelled in this way, the result argument of
#GtkWidget::drag-failed is set to GTK_DRAG_RESULT_ERROR.
Cancels an ongoing drag operation on the source side.
If you want to be able to cancel a drag operation in this way, you need to keep a pointer to the drag context, either from an explicit call to gtk.widget.Widget.dragBeginWithCoordinates, or by connecting to #GtkWidget::drag-begin.
If context does not refer to an ongoing drag operation, this function does nothing.
If a drag is cancelled in this way, the result argument of #GtkWidget::drag-failed is set to GTK_DRAG_RESULT_ERROR.