nsIDragService
nsidragsession getcurrentsession( ) ; void invokedragsession( in nsidomnode adomnode, in nsisupportsarray atransferables, in nsiscriptableregion aregion, in unsigned long aactiontype ); void invokedragsessionwithimage(in nsidomnode adomnode, in nsisupportsarray atransferablearray, in nsiscriptableregion aregion, in unsigned long aactiontype, in nsidomnode aimage, in long aimagex, in long aimagey, in nsidomdragevent adragevent, in nsidomdatatransfer adatatransfer); void invokedragsessionwithselection(in nsiselection asel...
... invokedragsession() starts a modal drag session with an array of transferables void invokedragsession( in nsidomnode adomnode, in nsisupportsarray atransferables, in nsiscriptableregion aregion, in unsigned long aactiontype ); parameters adomnode the source node on which the drag gesture was started.
... void invokedragsessionwithimage( in nsidomnode adomnode, in nsisupportsarray atransferablearray, in nsiscriptableregion aregion, in unsigned long aactiontype, in nsidomnode aimage, in long aimagex, in long aimagey, in nsidomdragevent adragevent, in nsidomdatatransfer adatatransfer ); parameters adomnode the source node on which the drag gesture was started.

nsITreeBoxObject
selectionregion nsiscriptableregion readonly: return the region for the visible parts of the selection, in device pixels.